multicast
The spanning-tree protocol sends Bridge Protocol Data Units (BPDUs) to a known data-link-layer multicast address. The first bit transmitted of the Ethernet or Token Ring (or whatever) address is a one, meaning it's a group (multicast) address. The Cisco switching books and classes seem to be teaching multicast in a bizarre way that is leaving people with the impression that it's an IP thing. Multicasting at the data-link layer has been in use for about 20 years. IP multicasting, although always supported by IP RFCs, has just started to get popular. Hope that makes sense. Priscilla At 03:47 PM 1/25/01, you wrote: >Actually I thought the MAC address used by STP was using a well known >MAC but it wasn't actually a Multicast MAC? > >Darren > >Priscilla Oppenheimer wrote: > > > > At 03:49 PM 1/24/01, Jim Dixon wrote: > > >Wouldn't that make it layer 2? > > >A bridge then? > > >Broadcast and don't care if I get a response? > > > > Bridges don't broadcast. They send multicasts for the spanning-tree > > algorithm, but that's not relevant. They forward broadcasts (and other > > frames), but that's not relevant either. We're talking about a single > > subnet that has two devices. The two devices probably aren't bridges. What > > would be the point of connecting two bridges together in one subnet that > > allows only two devices? > > > > Whether I get a response or not depends on what upper layer I'm using. For > > example, I could use ping to send a message from the first device > > (10.0.0.0/31) to the second device (10.0.0.1/31) on a point-to-point link. > > I should get a response (assuming the operating system would let me > > configure these addresses to start with.) > > > > If it's two routers on the ends of this point-to-point link, they are > > mostly just forwarding traffic on behalf of other stations. The IP > > addresses of the routers themselves are irrelevant in that case. In fact, I > > could use ip unnumbered, but then I couldn't ping the point-to-point > > interfaces, which makes management a bit harder. > > > > >Since I can't tell if anyone > > >is actually there, I just know that > > >someone is sending me broadcasts from somewhere on this link. > > > > What does "somewhere on this link" mean? It's a point-to-point link. > > There's only one other thing besides myself on the link. > > > > If I yell into a room that has only one person in it, "Hello, I'm trying to > > reach everyone in this room," won't I get an answer? Does it matter that I > > wasn't more precise? No... > > > > >Correct me if my thinking is in > > >need of more coffee. > > > > You need more coffee. (or maybe less??) &;-) > > > > Priscilla > > > > P.S. Please don't send messages directly to me. Please address them to the > > group. Thanks. > > > > >Jim :) > > > > > >-Original Message- > > >From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] > > >Sent: Wednesday, January 24, 2001 3:17 PM > > >To: Jeff McCoy; [EMAIL PROTECTED] > > >Subject: Re: slash 31 address > > > > > > > > >Yes, but on a point-to-point link, so what if you use the network number > > >and broadcast address to identify the two nodes? If one station sends to > > >the broadcast address it's not a problem, there's only one other station > > >anyway! I think /31 should be allowed on point-to-point links. > > > > > >Priscilla > > > > > >At 08:22 AM 1/24/01, Jeff McCoy wrote: > > > > > > >Michael... > > > >/30 = 4 address (1st is network number, 2 & 3 host ip's, 4th is > broadcast > > > >address) > > > >/31 = 2 address (1st is network number, 2nd is broadcast address) > > > > no host ip's...this is not useful.. > > > >/32 = 1 address (1 host address) i use this for loopbacks > > > > > > > > > > > >""Neil Schneider"" <[EMAIL PROTECTED]> wrote in message > > > >94mool$d33$[EMAIL PROTECTED]">news:94mool$d33$[EMAIL PROTECTED]... > > > > > AFAIK you can only go as far as /30. > > > > > > > > > > Neil Schneider > > > > > > > > > > <[EMAIL PROTECTED]> wrote in message > > > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > > > > > > > > > > > > > > > Hello good guys of the group, can anyone with the knowledge of > ip/31, > > > >help > > > > > me? > > > > > > please. > > > > > > > > > > > > I need to know what it is use for, and how it works, pls. > > > > > > > > > > > > Thanks in advance, > > > > > > > > > > > > Michael Taiwo. > > > > > > > > > > > > > > Priscilla Oppenheimer > > http://www.priscilla.com > > > > _ > > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Priscilla Oppenheimer http://www.priscilla.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast
We know there are some D class address if specificed for certain purpose and some are reserved for certain service. If I want to set up a real server and use multicast, what can I do? I can not get the D class address for my server! _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast
>From what I have read so far, they only tell you what you need on a router (IGMP) and what you need on switch (CGMP) to be able to do multicasting. What about the host? Does it also need a protocol installed? Tks, Bernard ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast
I am trying to implement multicast routing between to routers. I am not sure where to begin. Which routing protocol is best for this(IGMP, BGP?, etc.). Basically I am trying to test Norton Ghost enterprise between routers. Router A-- S0/0 10.254.254.1 E0/0 10.10.10.1 Router B-- S0/0 10.243.253.1 E0/0 10.10.20.1 Thanks in advance for your help. Thanks, Dennis Olson Dynamic Network Solutions, Inc. [EMAIL PROTECTED] http://www.dlolson.com 602-578-7121 ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast
REAL Server ??? Real Networks Streaming Server or ??? If you talking about the obove, just give it normal IP address. Sofware on the server should take care of the rest. + Configure routers for mulitcast "thinkworker" <[EMAIL PROTECTED]> wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > We know there are some D class address if specificed for certain purpose and some are reserved for certain service. > > If I want to set up a real server and use multicast, what can I do? I can not get the D class address for my server! > > > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast
For the Streaming Server : You can use Windows 2K Adavance Server it comes with a Streaming Server component , use the wizard to create a .nsc as well as a .asx file a random multicast address will be generated For the Router : You need to enable multicast routing set ip pim dense-mode and put in a igmp static group regards, suaveguru --- thinkworker <[EMAIL PROTECTED]> wrote: > We know there are some D class address if specificed > for certain purpose and some are reserved for > certain service. > > If I want to set up a real server and use multicast, > what can I do? I can not get the D class address for > my server! > > > > _ > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] __ Do You Yahoo!? Yahoo! Auctions - Buy the things you want at great prices. http://auctions.yahoo.com/ _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
ftp multicast
anyone knows what ftp multicast is? what is the difference between ftp and ftp multicast? _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
multicast address
Hi, Can somebody explain me how to convert an multicast IP address for e.g (224.0.0.6) into multicast mac address. TIA, -Subbi. ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast software
I am studying for the BCMSN exam and I would like to do some testing with multicasting. Does anyone know were I can download a shareware multicast server and client. Thanks ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast
yes: an example of a multicat protocol is SLP . novell 5 and sun use this protocol to find services in the network clients do need a multicast protocol pq Bernard <[EMAIL PROTECTED]> wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > From what I have read so far, they only tell you what you need on a router > (IGMP) and what you need on switch (CGMP) to be able to do multicasting. > > What about the host? > Does it also need a protocol installed? > > Tks, > Bernard > > > ___ > UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html > FAQ, list archives, and subscription info: http://www.groupstudy.com > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > --- ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast
Have you enabled multicast routing on the routers?
Scott
In article <003201bfd604$2755c950$c3b63fd1@W21> , [EMAIL PROTECTED]
("Dennis Olson") wrote:
> I am trying to implement multicast routing between to routers. I am not sure
> where to begin. Which routing protocol is best for this(IGMP, BGP?, etc.).
> Basically I am trying to test Norton Ghost enterprise between routers.
> Router A--
> S0/0 10.254.254.1
> E0/0 10.10.10.1
> Router B--
> S0/0 10.243.253.1
> E0/0 10.10.20.1
>
> Thanks in advance for your help.
>
> Thanks,
--
Scott Nelson - Network Engineer
Wash DC +1202-270-8968
Los Angeles +1310-367-6646
mailto:[EMAIL PROTECTED]
--
"UPIC's (Uninformed People In Charge) reading about the "latest and
Greatest" bell or whistle but no thought at all to how it integrates,
what it costs, what it takes to support it, or how it is supported."
-- Donald N. Gallagher
--
___
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Re: Multicast
how about this on each router do this on global config ip multicast-routing ---this enables multicast routing on each interface do this ip pim dense-mode Dude visit this site http://www.cisco.com/warp/public/105/48.html ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
multicast / CGMP towards the multicast server [7:33963]
If a multicast server is connected to a Cisco Switch running CGMP, and several hosts are connected to the same switch, will a router turn off the switch ports for the users that are not requesting the multicast? So, will CGMP work back towards the multicast server? Fears Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=33963&t=33963 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
multicast / CGMP towards the multicast server [7:33964]
If a multicast server is connected to a Cisco Switch running CGMP, and several hosts are connected to the same switch, will a router turn off the switch ports for the users that are not requesting the multicast? So, will CGMP work back towards the multicast server? Fears Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=33964&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast / CGMP towards the multicast server [7:33964]
If by turn off the port you mean not send the multicast stream to that port then yes. Assuming you have it configured correctly. ""Fears Michael S SSgt 50 CS/SCBBN"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > If a multicast server is connected to a Cisco Switch running CGMP, and > several hosts are connected to the same switch, will a router turn off the > switch ports for the users that are not requesting the multicast? > > So, will CGMP work back towards the multicast server? > > Fears Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=33983&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast / CGMP towards the multicast server [7:33964]
Michael, Of course this would depend on if the multicast server and the host connected on the same switch was assigned to the same vlan(broadcast domain). Just some quick points to mention.. Routers by default will not forward multicast traffic. However, if you enabled a multicast routing protocol(PIM, DVMRP) then this is possible. The important thing here is that IGMP is used by hosts to inform routers of their intent to become part of a multicast stream. This depends on your implementation of the multicast protocol. IGMPv2 has been improved to support leaves from a multicast group which is not supported in IGMPv1. This way the host is able to notify the source of it's intent to leave the multicast group. This is will allow the routers to prune the multicast traffic from the segment removing the unnecessary traffic, providing no other host on the segment remains a member of the multicast stream A good title as recommended by a number of folks on the list is Developing IP Multicast Networks Author: Beau Williamson. ISBN: 157870779 HTH Nigel Original Message - From: "Fears Michael S SSgt 50 CS/SCBBN" To: Sent: Thursday, January 31, 2002 4:59 PM Subject: multicast / CGMP towards the multicast server [7:33964] > If a multicast server is connected to a Cisco Switch running CGMP, and > several hosts are connected to the same switch, will a router turn off the > switch ports for the users that are not requesting the multicast? > > So, will CGMP work back towards the multicast server? > > Fears Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=34001&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: multicast / CGMP towards the multicast server [7:33964]
Nigel, Thanks, Yes the switch and users are all on the same VLAN. PIM and IGMP are working fine across the router and into other CGMP enable switches. The thing I was not sure of, was: if I have a server multicasting on the same switch/VLAN as other users, can I prevent the multicast stream from flooding the broadcast domain that the server is in? I was asked this question and my answer was "no". I thought it was just poor design to have the multicast server on the same VLAN as the users who are not using it. Maybe I'm wrong?? -Original Message- From: Nigel Taylor [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 31, 2002 8:19 PM To: [EMAIL PROTECTED] Subject: Re: multicast / CGMP towards the multicast server [7:33964] Michael, Of course this would depend on if the multicast server and the host connected on the same switch was assigned to the same vlan(broadcast domain). Just some quick points to mention.. Routers by default will not forward multicast traffic. However, if you enabled a multicast routing protocol(PIM, DVMRP) then this is possible. The important thing here is that IGMP is used by hosts to inform routers of their intent to become part of a multicast stream. This depends on your implementation of the multicast protocol. IGMPv2 has been improved to support leaves from a multicast group which is not supported in IGMPv1. This way the host is able to notify the source of it's intent to leave the multicast group. This is will allow the routers to prune the multicast traffic from the segment removing the unnecessary traffic, providing no other host on the segment remains a member of the multicast stream A good title as recommended by a number of folks on the list is Developing IP Multicast Networks Author: Beau Williamson. ISBN: 157870779 HTH Nigel Original Message - From: "Fears Michael S SSgt 50 CS/SCBBN" To: Sent: Thursday, January 31, 2002 4:59 PM Subject: multicast / CGMP towards the multicast server [7:33964] > If a multicast server is connected to a Cisco Switch running CGMP, and > several hosts are connected to the same switch, will a router turn off the > switch ports for the users that are not requesting the multicast? > > So, will CGMP work back towards the multicast server? > > Fears Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=34052&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast / CGMP towards the multicast server [7:33964]
As long as there is a multicast router connected to the switch, and CGMP is enabled on that switch, then yes, the router will control flooding of multicast traffic on the switch ports. CM - Original Message - From: "Fears Michael S SSgt 50 CS/SCBBN" To: Sent: Friday, February 01, 2002 1:57 PM Subject: RE: multicast / CGMP towards the multicast server [7:33964] > Nigel, Thanks, Yes the switch and users are all on the same VLAN. PIM and > IGMP > are working fine across the router and into other CGMP enable switches. > The thing I was not sure of, was: if I have a server multicasting > on the same switch/VLAN as other users, can I prevent the multicast > stream from flooding the broadcast domain that the server is in? > > I was asked this question and my answer was "no". I thought it was just poor > design > to have the multicast server on the same VLAN as the users who are not using > it. > > Maybe I'm wrong?? > > > > > > -Original Message- > From: Nigel Taylor [mailto:[EMAIL PROTECTED]] > Sent: Thursday, January 31, 2002 8:19 PM > To: [EMAIL PROTECTED] > Subject: Re: multicast / CGMP towards the multicast server [7:33964] > > > Michael, > Of course this would depend on if the multicast server and the > host connected on the same switch was assigned to the same vlan(broadcast > domain). Just some quick points to mention.. > > Routers by default will not forward multicast traffic. However, if you > enabled a multicast routing protocol(PIM, DVMRP) then this is possible. The > important thing here is that IGMP is used by hosts to inform routers of > their intent to become part of a multicast stream. This depends on your > implementation of the multicast protocol. IGMPv2 has been improved to > support leaves from a multicast group which is not supported in IGMPv1. > This way the host is able to notify the source of it's intent to leave the > multicast group. This is will allow the routers to prune the multicast > traffic from the segment removing the unnecessary traffic, providing no > other host on the segment remains a member of the multicast stream > > A good title as recommended by a number of folks on the list is Developing > IP Multicast Networks > Author: Beau Williamson. ISBN: 157870779 > > HTH > > Nigel > > > > Original Message - > From: "Fears Michael S SSgt 50 CS/SCBBN" > To: > Sent: Thursday, January 31, 2002 4:59 PM > Subject: multicast / CGMP towards the multicast server [7:33964] > > > > If a multicast server is connected to a Cisco Switch running CGMP, and > > several hosts are connected to the same switch, will a router turn off the > > switch ports for the users that are not requesting the multicast? > > > > So, will CGMP work back towards the multicast server? > > > > Fears Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=34055&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: multicast / CGMP towards the multicast server [7:33964]
When a multicast reciever wishes to recieve multicast traffic it must send an IGMP join for the multicast group. CGMP/IGMP snooping get in the way of this and makes sure the stream only goes to needed ports. A multicast sender doesn't need to send an IGMP join to the router to start sending multicasts (that can't be a requirement, because if it was what would happen on multicast networks without routers?) A sender simply starts sending packets. Because a sender doesn't send IGMP joins CGMP and IGMP snooping cannot function. Kinda sucks huh? If your intrested I'm working on an open source multicast project that simulates multicast traffic at http://sourceforge.net/projects/mc-mint/ If you want you can look at the souce and you'll see the sender function doesn't use IGMP joins. Mike --- Mike Bernico [EMAIL PROTECTED] Illinois Century Network http://www.illinois.net (217) 557-6555 > -Original Message- > From: Fears Michael S SSgt 50 CS/SCBBN > [mailto:[EMAIL PROTECTED]] > Sent: Friday, February 01, 2002 7:58 AM > To: [EMAIL PROTECTED] > Subject: RE: multicast / CGMP towards the multicast server [7:33964] > > > Nigel, Thanks, Yes the switch and users are all on the same > VLAN. PIM and > IGMP > are working fine across the router and into other CGMP enable > switches. > The thing I was not sure of, was: if I have a server multicasting > on the same switch/VLAN as other users, can I prevent the multicast > stream from flooding the broadcast domain that the server is in? > > I was asked this question and my answer was "no". I thought > it was just poor > design > to have the multicast server on the same VLAN as the users > who are not using > it. > > Maybe I'm wrong?? > > > > > > -Original Message- > From: Nigel Taylor [mailto:[EMAIL PROTECTED]] > Sent: Thursday, January 31, 2002 8:19 PM > To: [EMAIL PROTECTED] > Subject: Re: multicast / CGMP towards the multicast server [7:33964] > > > Michael, > Of course this would depend on if the multicast > server and the > host connected on the same switch was assigned to the same > vlan(broadcast > domain). Just some quick points to mention.. > > Routers by default will not forward multicast traffic. > However, if you > enabled a multicast routing protocol(PIM, DVMRP) then this is > possible. The > important thing here is that IGMP is used by hosts to inform > routers of > their intent to become part of a multicast stream. This > depends on your > implementation of the multicast protocol. IGMPv2 has been improved to > support leaves from a multicast group which is not supported > in IGMPv1. > This way the host is able to notify the source of it's intent > to leave the > multicast group. This is will allow the routers to prune the > multicast > traffic from the segment removing the unnecessary traffic, > providing no > other host on the segment remains a member of the multicast stream > > A good title as recommended by a number of folks on the list > is Developing > IP Multicast Networks > Author: Beau Williamson. ISBN: 157870779 > > HTH > > Nigel > > > > Original Message - > From: "Fears Michael S SSgt 50 CS/SCBBN" > To: > Sent: Thursday, January 31, 2002 4:59 PM > Subject: multicast / CGMP towards the multicast server [7:33964] > > > > If a multicast server is connected to a Cisco Switch > running CGMP, and > > several hosts are connected to the same switch, will a > router turn off the > > switch ports for the users that are not requesting the multicast? > > > > So, will CGMP work back towards the multicast server? > > > > Fears Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=34061&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast / CGMP towards the multicast server [7:33964]
No offence, but that answer doesn't remove the quandary. The entire switch is a segment from the router's point of view. The router receives the IGMP Join and now knows that packets for that multicast group must be sent out that interface to that Ethernet segment. All devices on the switch are out that interface, however. What Fears fears is that the router won't be smart enough to tell the switch that not all devices connected to the switch should receive the multicast stream. But fear not, Fears. CGMP is smarter than you might think. Here's how I understand it. Correct me if I'm wrong, please (anyone). As you know, when a host wants to join an IP multicast group, it sends an IGMP Join message. The Join specifies the host's MAC address and the IP multicast group that it wants to join. When a router receives the IGMP Join, it creates a CGMP message that contains the MAC address of the host and the multicast group address. The router sends the CGMP message to a well-known address that all switches listen to. When a Catalyst switch receives the CGMP message from the router, the supervisor engine responds by modifying the forwarding table automatically. In other words, it now knows the specific port that must receive the multicast stream. Other hosts on different ports may Join also, and the switch will add them to the table. This is different from IGMP Snooping, by the way. From what I understand, IGMP Snooping allows the switch to proactively snoop into IGMP packets and figure out which ones are Joins. IGMP Snooping requires more powerful (and more expensive) switching hardware (firmware). Priscilla At 10:18 PM 1/31/02, Nigel Taylor wrote: >Michael, > Of course this would depend on if the multicast server and the >host connected on the same switch was assigned to the same vlan(broadcast >domain). Just some quick points to mention.. > >Routers by default will not forward multicast traffic. However, if you >enabled a multicast routing protocol(PIM, DVMRP) then this is possible. The >important thing here is that IGMP is used by hosts to inform routers of >their intent to become part of a multicast stream. This depends on your >implementation of the multicast protocol. IGMPv2 has been improved to >support leaves from a multicast group which is not supported in IGMPv1. >This way the host is able to notify the source of it's intent to leave the >multicast group. This is will allow the routers to prune the multicast >traffic from the segment removing the unnecessary traffic, providing no >other host on the segment remains a member of the multicast stream > >A good title as recommended by a number of folks on the list is Developing >IP Multicast Networks >Author: Beau Williamson. ISBN: 157870779 > >HTH > >Nigel > > > > Original Message - >From: "Fears Michael S SSgt 50 CS/SCBBN" >To: >Sent: Thursday, January 31, 2002 4:59 PM >Subject: multicast / CGMP towards the multicast server [7:33964] > > > > If a multicast server is connected to a Cisco Switch running CGMP, and > > several hosts are connected to the same switch, will a router turn off the > > switch ports for the users that are not requesting the multicast? > > > > So, will CGMP work back towards the multicast server? > > > > Fears Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=34099&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast / CGMP towards the multicast server [7:33964]
Priscilla, You are correct. Thanks for the added insight. Nigel - Original Message - From: "Priscilla Oppenheimer" To: Sent: Friday, February 01, 2002 2:03 PM Subject: Re: multicast / CGMP towards the multicast server [7:33964] > No offence, but that answer doesn't remove the quandary. The entire switch > is a segment from the router's point of view. The router receives the IGMP > Join and now knows that packets for that multicast group must be sent out > that interface to that Ethernet segment. All devices on the switch are out > that interface, however. > > What Fears fears is that the router won't be smart enough to tell the > switch that not all devices connected to the switch should receive the > multicast stream. > > But fear not, Fears. CGMP is smarter than you might think. Here's how I > understand it. Correct me if I'm wrong, please (anyone). > > As you know, when a host wants to join an IP multicast group, it sends an > IGMP Join message. The Join specifies the host's MAC address and the IP > multicast group that it wants to join. > > When a router receives the IGMP Join, it creates a CGMP message that > contains the MAC address of the host and the multicast group address. The > router sends the CGMP message to a well-known address that all switches > listen to. When a Catalyst switch receives the CGMP message from the > router, the supervisor engine responds by modifying the forwarding table > automatically. In other words, it now knows the specific port that must > receive the multicast stream. Other hosts on different ports may Join also, > and the switch will add them to the table. > > This is different from IGMP Snooping, by the way. From what I understand, > IGMP Snooping allows the switch to proactively snoop into IGMP packets and > figure out which ones are Joins. IGMP Snooping requires more powerful (and > more expensive) switching hardware (firmware). > > Priscilla > > At 10:18 PM 1/31/02, Nigel Taylor wrote: > >Michael, > > Of course this would depend on if the multicast server and the > >host connected on the same switch was assigned to the same vlan(broadcast > >domain). Just some quick points to mention.. > > > >Routers by default will not forward multicast traffic. However, if you > >enabled a multicast routing protocol(PIM, DVMRP) then this is possible. The > >important thing here is that IGMP is used by hosts to inform routers of > >their intent to become part of a multicast stream. This depends on your > >implementation of the multicast protocol. IGMPv2 has been improved to > >support leaves from a multicast group which is not supported in IGMPv1. > >This way the host is able to notify the source of it's intent to leave the > >multicast group. This is will allow the routers to prune the multicast > >traffic from the segment removing the unnecessary traffic, providing no > >other host on the segment remains a member of the multicast stream > > > >A good title as recommended by a number of folks on the list is Developing > >IP Multicast Networks > >Author: Beau Williamson. ISBN: 157870779 > > > >HTH > > > >Nigel > > > > > > > > Original Message - > >From: "Fears Michael S SSgt 50 CS/SCBBN" > >To: > >Sent: Thursday, January 31, 2002 4:59 PM > >Subject: multicast / CGMP towards the multicast server [7:33964] > > > > > > > If a multicast server is connected to a Cisco Switch running CGMP, and > > > several hosts are connected to the same switch, will a router turn off > the > > > switch ports for the users that are not requesting the multicast? > > > > > > So, will CGMP work back towards the multicast server? > > > > > > Fears > > > Priscilla Oppenheimer > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=34159&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast / CGMP towards the multicast server [7:33964]
At 09:28 PM 2/1/02, Nigel Taylor wrote: >Priscilla, > You are correct. Thanks for the added insight. > >Nigel You are nice to say this, but you know what I realized?! My answer doesn't resolve the quandary either! ;-) I now think that Fears' real fears had to do with the recipients and the server being on the same VLAN. This might cause the switch to forward the multicast traffic before it even checks the results of CGMP. The switch may do its default multicast flooding to ports in a VLAN and just make use of CGMP to learn about other ports. Am I making any sense? It's late. ;-) My guess it that the answer is still that CGMP is smart. Once you configure it, the switch knows to not do its normal multicast flooding and instead wait to hear from the router regarding which ports should receive the multicast flow. Hopefully someone can confirm that. Priscilla >- Original Message - >From: "Priscilla Oppenheimer" >To: >Sent: Friday, February 01, 2002 2:03 PM >Subject: Re: multicast / CGMP towards the multicast server [7:33964] > > > > No offence, but that answer doesn't remove the quandary. The entire switch > > is a segment from the router's point of view. The router receives the IGMP > > Join and now knows that packets for that multicast group must be sent out > > that interface to that Ethernet segment. All devices on the switch are out > > that interface, however. > > > > What Fears fears is that the router won't be smart enough to tell the > > switch that not all devices connected to the switch should receive the > > multicast stream. > > > > But fear not, Fears. CGMP is smarter than you might think. Here's how I > > understand it. Correct me if I'm wrong, please (anyone). > > > > As you know, when a host wants to join an IP multicast group, it sends an > > IGMP Join message. The Join specifies the host's MAC address and the IP > > multicast group that it wants to join. > > > > When a router receives the IGMP Join, it creates a CGMP message that > > contains the MAC address of the host and the multicast group address. The > > router sends the CGMP message to a well-known address that all switches > > listen to. When a Catalyst switch receives the CGMP message from the > > router, the supervisor engine responds by modifying the forwarding table > > automatically. In other words, it now knows the specific port that must > > receive the multicast stream. Other hosts on different ports may Join >also, > > and the switch will add them to the table. > > > > This is different from IGMP Snooping, by the way. From what I understand, > > IGMP Snooping allows the switch to proactively snoop into IGMP packets and > > figure out which ones are Joins. IGMP Snooping requires more powerful (and > > more expensive) switching hardware (firmware). > > > > Priscilla > > > > At 10:18 PM 1/31/02, Nigel Taylor wrote: > > >Michael, > > > Of course this would depend on if the multicast server and >the > > >host connected on the same switch was assigned to the same vlan(broadcast > > >domain). Just some quick points to mention.. > > > > > >Routers by default will not forward multicast traffic. However, if you > > >enabled a multicast routing protocol(PIM, DVMRP) then this is possible. >The > > >important thing here is that IGMP is used by hosts to inform routers of > > >their intent to become part of a multicast stream. This depends on your > > >implementation of the multicast protocol. IGMPv2 has been improved to > > >support leaves from a multicast group which is not supported in IGMPv1. > > >This way the host is able to notify the source of it's intent to leave >the > > >multicast group. This is will allow the routers to prune the multicast > > >traffic from the segment removing the unnecessary traffic, providing no > > >other host on the segment remains a member of the multicast stream > > > > > >A good title as recommended by a number of folks on the list is >Developing > > >IP Multicast Networks > > >Author: Beau Williamson. ISBN: 157870779 > > > > > >HTH > > > > > >Nigel > > > > > > > > > > > > Original Message - > > >From: "Fears Michael S SSgt 50 CS/SCBBN" > > >To: > > >Sent: Thursday, January 31, 2002 4:59 PM > > >Subject: multicast / CGMP towards the multicast server [7:33964] > > > > > > > > > > If a multicast server is connected
Re: multicast / CGMP towards the multicast server [7:33964]
Priscilla, You're correct in that Fears' real fear at this point has not been answered. ;-> In doing some quick research, I found that as you mentioned IGMP(costly) and CGMP(a less costly solution) would assist in providing one the ability to control multicast flooding. This is what I found... Even in an design where the host and the server resides on the same VLAN(segment) IGMP and CGMP still provides the ability to control flooding of multicast traffic. Specifically, when the host multicasts the IGMP membership report to the group with the address 224.1.2.3(MAC 0x0100.5E01.0203) and there's no existing mapping in it's CAM table, the switch will flood the report on all ports in the VLAN. However, any futher attempts to join that existing group would then be limited to port listed in the CAM table that are eligible to recieve the multicast traffic for the group. Chptr 14, pgs 412-442 of Beau Williamson's book Developing IP Multicast Network provides some really good info on this issue. The author does note that flat switched LAN designs will present major problems in gaining/maintaining control of multicast flooding. I guess this really comes down to the network design as with every other aspect of building a scalable and efficient network. Thoughts.. Anyone! Nigel > At 09:28 PM 2/1/02, Nigel Taylor wrote: > >Priscilla, > > You are correct. Thanks for the added insight. > > > >Nigel > > You are nice to say this, but you know what I realized?! My answer doesn't > resolve the quandary either! ;-) > > I now think that Fears' real fears had to do with the recipients and the > server being on the same VLAN. This might cause the switch to forward the > multicast traffic before it even checks the results of CGMP. The switch may > do its default multicast flooding to ports in a VLAN and just make use of > CGMP to learn about other ports. Am I making any sense? It's late. ;-) > > My guess it that the answer is still that CGMP is smart. Once you configure > it, the switch knows to not do its normal multicast flooding and instead > wait to hear from the router regarding which ports should receive the > multicast flow. Hopefully someone can confirm that. > > Priscilla > > > >- Original Message - > >From: "Priscilla Oppenheimer" > >To: > >Sent: Friday, February 01, 2002 2:03 PM > >Subject: Re: multicast / CGMP towards the multicast server [7:33964] > > > > > > > No offence, but that answer doesn't remove the quandary. The entire > switch > > > is a segment from the router's point of view. The router receives the > IGMP > > > Join and now knows that packets for that multicast group must be sent out > > > that interface to that Ethernet segment. All devices on the switch are > out > > > that interface, however. > > > > > > What Fears fears is that the router won't be smart enough to tell the > > > switch that not all devices connected to the switch should receive the > > > multicast stream. > > > > > > But fear not, Fears. CGMP is smarter than you might think. Here's how I > > > understand it. Correct me if I'm wrong, please (anyone). > > > > > > As you know, when a host wants to join an IP multicast group, it sends an > > > IGMP Join message. The Join specifies the host's MAC address and the IP > > > multicast group that it wants to join. > > > > > > When a router receives the IGMP Join, it creates a CGMP message that > > > contains the MAC address of the host and the multicast group address. The > > > router sends the CGMP message to a well-known address that all switches > > > listen to. When a Catalyst switch receives the CGMP message from the > > > router, the supervisor engine responds by modifying the forwarding table > > > automatically. In other words, it now knows the specific port that must > > > receive the multicast stream. Other hosts on different ports may Join > >also, > > > and the switch will add them to the table. > > > > > > This is different from IGMP Snooping, by the way. From what I understand, > > > IGMP Snooping allows the switch to proactively snoop into IGMP packets > and > > > figure out which ones are Joins. IGMP Snooping requires more powerful > (and > > > more expensive) switching hardware (firmware). > > > > > > Priscilla > > > > > > At 10:18 PM 1/31/02, Nigel Taylor wrote: > > > >Michael, > > > > Of course this would depend on if the multicast server and > >the > >
Re: multicast / CGMP towards the multicast server [7:33964]
Added note for anyone who may be interested:: The well-known CGMP multicast MAC address is: 0x0100,0cdd,, dj ""Nigel Taylor"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Priscilla, > You're correct in that Fears' real fear at this point has not > been answered. ;-> In doing some quick research, I found that as you > mentioned IGMP(costly) and CGMP(a less costly solution) would assist in > providing one the ability to control multicast flooding. This is what I > found... > > Even in an design where the host and the server resides on the same > VLAN(segment) IGMP and CGMP still provides the ability to control flooding > of multicast traffic. Specifically, when the host multicasts the IGMP > membership report to the group with the address 224.1.2.3(MAC > 0x0100.5E01.0203) and there's no existing mapping in it's CAM table, the > switch will flood the report on all ports in the VLAN. However, any futher > attempts to join that existing group would then be limited to port listed in > the CAM table that are eligible to recieve the multicast traffic for the > group. Chptr 14, pgs 412-442 of Beau Williamson's book Developing IP > Multicast Network provides some really good info on this issue. The author > does note that flat switched LAN designs will present major problems in > gaining/maintaining control of multicast flooding. > > I guess this really comes down to the network design as with every other > aspect of building a scalable and efficient network. > > Thoughts.. Anyone! > > Nigel > > > > > > At 09:28 PM 2/1/02, Nigel Taylor wrote: > > >Priscilla, > > > You are correct. Thanks for the added insight. > > > > > >Nigel > > > > You are nice to say this, but you know what I realized?! My answer doesn't > > resolve the quandary either! ;-) > > > > I now think that Fears' real fears had to do with the recipients and the > > server being on the same VLAN. This might cause the switch to forward the > > multicast traffic before it even checks the results of CGMP. The switch > may > > do its default multicast flooding to ports in a VLAN and just make use of > > CGMP to learn about other ports. Am I making any sense? It's late. ;-) > > > > My guess it that the answer is still that CGMP is smart. Once you > configure > > it, the switch knows to not do its normal multicast flooding and instead > > wait to hear from the router regarding which ports should receive the > > multicast flow. Hopefully someone can confirm that. > > > > Priscilla > > > > > > >- Original Message - > > >From: "Priscilla Oppenheimer" > > >To: > > >Sent: Friday, February 01, 2002 2:03 PM > > >Subject: Re: multicast / CGMP towards the multicast server [7:33964] > > > > > > > > > > No offence, but that answer doesn't remove the quandary. The entire > > switch > > > > is a segment from the router's point of view. The router receives the > > IGMP > > > > Join and now knows that packets for that multicast group must be sent > out > > > > that interface to that Ethernet segment. All devices on the switch are > > out > > > > that interface, however. > > > > > > > > What Fears fears is that the router won't be smart enough to tell the > > > > switch that not all devices connected to the switch should receive the > > > > multicast stream. > > > > > > > > But fear not, Fears. CGMP is smarter than you might think. Here's how > I > > > > understand it. Correct me if I'm wrong, please (anyone). > > > > > > > > As you know, when a host wants to join an IP multicast group, it sends > an > > > > IGMP Join message. The Join specifies the host's MAC address and the > IP > > > > multicast group that it wants to join. > > > > > > > > When a router receives the IGMP Join, it creates a CGMP message that > > > > contains the MAC address of the host and the multicast group address. > The > > > > router sends the CGMP message to a well-known address that all > switches > > > > listen to. When a Catalyst switch receives the CGMP message from the > > > > router, the supervisor engine responds by modifying the forwarding > table > > > > automatically. In other words, it now knows the specific port that > must > > > > receive the multicast stream. Other
Re: multicast / CGMP towards the multicast server [7:33964]
At 06:18 AM 2/2/02, Nigel Taylor wrote: >Even in an design where the host and the server reside on the same >VLAN(segment) IGMP and CGMP still provide the ability to control flooding >of multicast traffic. Specifically, when the host multicasts the IGMP >membership report to the group with the address 224.1.2.3(MAC >0x0100.5E01.0203) and there's no existing mapping in its CAM table, the >switch will flood the report on all ports in the VLAN. It's not the membership reports we're concerned about. It's the multicast traffic from the source multicast server. The question can be boiled down to this: When you enable CGMP does that mean the switch automatically stops flooding multicast traffic to all devices in the VLAN? Does the switch instead wait for the recipients to send their membership reports, which go to the router and then get converted into CGMP messages from the router to the switch? Only devices that have sent the membership report can receive the traffic. (There could be a problem if it works this way. The multicast server could start sending before anyone joined.) The question is not about basic IGMP and CGMP behavior. The question has to do with switch behavior in the special case where the source of the multicast traffic is on the same switch and in the same VLAN as the recipients. We're concerned because that sounds like it would cause normal multicast flooding to kick in. For that not to happen, the switch must be smarter than we're thinking. >However, any futher >attempts to join that existing group would then be limited to port listed in >the CAM table that are eligible to recieve the multicast traffic for the >group. Once again we're not talking about the membership reports (joins), although what you say is probably true. I wonder if what's also true is that the first membership report causes the switch to then not forward the server's multicast traffic to any devices not listed in the port list in the CAM table for the multicast address. That would make sense. Devices have to send their joins in order to get on the list and get the traffic. > Chptr 14, pgs 412-442 of Beau Williamson's book Developing IP >Multicast Network provides some really good info on this issue. I couldn't find an answer to our question. Maybe you could?? Thanks. And to add to the question I've been wondering about more ordinary multicasts, like OSPF Hellos and even BPDUs. If you enabled CGMP, would these not get sent to any devices that didn't implement IGMP and sent their membership report? That seems kind of ugly. Maybe it's not an issue because you would only use CGMP on the edge in switches that connect end devices. Priscilla >The author >does note that flat switched LAN designs will present major problems in >gaining/maintaining control of multicast flooding. > >I guess this really comes down to the network design as with every other >aspect of building a scalable and efficient network. > >Thoughts.. Anyone! > >Nigel > > > > > > At 09:28 PM 2/1/02, Nigel Taylor wrote: > > >Priscilla, > > > You are correct. Thanks for the added insight. > > > > > >Nigel > > > > You are nice to say this, but you know what I realized?! My answer doesn't > > resolve the quandary either! ;-) > > > > I now think that Fears' real fears had to do with the recipients and the > > server being on the same VLAN. This might cause the switch to forward the > > multicast traffic before it even checks the results of CGMP. The switch >may > > do its default multicast flooding to ports in a VLAN and just make use of > > CGMP to learn about other ports. Am I making any sense? It's late. ;-) > > > > My guess it that the answer is still that CGMP is smart. Once you >configure > > it, the switch knows to not do its normal multicast flooding and instead > > wait to hear from the router regarding which ports should receive the > > multicast flow. Hopefully someone can confirm that. > > > > Priscilla > > > > > > >- Original Message - > > >From: "Priscilla Oppenheimer" > > >To: > > >Sent: Friday, February 01, 2002 2:03 PM > > >Subject: Re: multicast / CGMP towards the multicast server [7:33964] > > > > > > > > > > No offence, but that answer doesn't remove the quandary. The entire > > switch > > > > is a segment from the router's point of view. The router receives the > > IGMP > > > > Join and now knows that packets for that multicast group must be sent >out > > > > that interface to that Ethernet segment. All devices on the switch a
Re: multicast / CGMP towards the multicast server [7:33964]
Like I said before, as long as you have a router connected to that segment (VLAN), multicast flooding will be constrained to the ports that have sent membership report. Non-registered clients will not be able to receive the multicast traffic, even though they are on the same VLAN as the sender. The router dynamically modifies the switch MAC table through CGMP messages. CM - Original Message - From: "Priscilla Oppenheimer" To: Sent: Saturday, February 02, 2002 11:22 PM Subject: Re: multicast / CGMP towards the multicast server [7:33964] > At 06:18 AM 2/2/02, Nigel Taylor wrote: > > >Even in an design where the host and the server reside on the same > >VLAN(segment) IGMP and CGMP still provide the ability to control flooding > >of multicast traffic. Specifically, when the host multicasts the IGMP > >membership report to the group with the address 224.1.2.3(MAC > >0x0100.5E01.0203) and there's no existing mapping in its CAM table, the > >switch will flood the report on all ports in the VLAN. > > It's not the membership reports we're concerned about. It's the multicast > traffic from the source multicast server. The question can be boiled down > to this: > > When you enable CGMP does that mean the switch automatically stops flooding > multicast traffic to all devices in the VLAN? Does the switch instead wait > for the recipients to send their membership reports, which go to the router > and then get converted into CGMP messages from the router to the switch? > Only devices that have sent the membership report can receive the traffic. > (There could be a problem if it works this way. The multicast server could > start sending before anyone joined.) > > The question is not about basic IGMP and CGMP behavior. The question has to > do with switch behavior in the special case where the source of the > multicast traffic is on the same switch and in the same VLAN as the > recipients. We're concerned because that sounds like it would cause normal > multicast flooding to kick in. For that not to happen, the switch must be > smarter than we're thinking. > > >However, any futher > >attempts to join that existing group would then be limited to port listed in > >the CAM table that are eligible to recieve the multicast traffic for the > >group. > > Once again we're not talking about the membership reports (joins), although > what you say is probably true. > > I wonder if what's also true is that the first membership report causes the > switch to then not forward the server's multicast traffic to any devices > not listed in the port list in the CAM table for the multicast address. > That would make sense. Devices have to send their joins in order to get on > the list and get the traffic. > > > Chptr 14, pgs 412-442 of Beau Williamson's book Developing IP > >Multicast Network provides some really good info on this issue. > > I couldn't find an answer to our question. Maybe you could?? Thanks. > > And to add to the question I've been wondering about more ordinary > multicasts, like OSPF Hellos and even BPDUs. If you enabled CGMP, would > these not get sent to any devices that didn't implement IGMP and sent their > membership report? That seems kind of ugly. Maybe it's not an issue because > you would only use CGMP on the edge in switches that connect end devices. > > Priscilla > > >The author > >does note that flat switched LAN designs will present major problems in > >gaining/maintaining control of multicast flooding. > > > >I guess this really comes down to the network design as with every other > >aspect of building a scalable and efficient network. > > > >Thoughts.. Anyone! > > > >Nigel > > > > > > > > > > > At 09:28 PM 2/1/02, Nigel Taylor wrote: > > > >Priscilla, > > > > You are correct. Thanks for the added insight. > > > > > > > >Nigel > > > > > > You are nice to say this, but you know what I realized?! My answer > doesn't > > > resolve the quandary either! ;-) > > > > > > I now think that Fears' real fears had to do with the recipients and the > > > server being on the same VLAN. This might cause the switch to forward the > > > multicast traffic before it even checks the results of CGMP. The switch > >may > > > do its default multicast flooding to ports in a VLAN and just make use of > > > CGMP to learn about other ports. Am I making any sense? It's late. ;-) > > > > > > My guess it that the answer is still that CGMP is smart. Once you > >
Re: multicast / CGMP towards the multicast server [7:33964]
Priscilla, I had to search out the answer. I found myself getting up because I couldn't sleep. I believe I found what we were looking for..see Inline. - Original Message - From: "Priscilla Oppenheimer" To: Sent: Saturday, February 02, 2002 6:22 PM Subject: Re: multicast / CGMP towards the multicast server [7:33964] > At 06:18 AM 2/2/02, Nigel Taylor wrote: > > >Even in an design where the host and the server reside on the same > >VLAN(segment) IGMP and CGMP still provide the ability to control flooding > >of multicast traffic. Specifically, when the host multicasts the IGMP > >membership report to the group with the address 224.1.2.3(MAC > >0x0100.5E01.0203) and there's no existing mapping in its CAM table, the > >switch will flood the report on all ports in the VLAN. > > It's not the membership reports we're concerned about. It's the multicast > traffic from the source multicast server. The question can be boiled down > to this: > It would seem that in this case the membership reports is all that we would need to care about. > When you enable CGMP does that mean the switch automatically stops flooding > multicast traffic to all devices in the VLAN? Does the switch instead wait > for the recipients to send their membership reports, which go to the router > and then get converted into CGMP messages from the router to the switch? > Only devices that have sent the membership report can receive the traffic. > (There could be a problem if it works this way. The multicast server could > start sending before anyone joined.) No, when CGMP is enabled on the switch it does not stop the flooding of multicast to all devices in the VLAN. However, as you mention the switch does not wait until the recipients send their membership reports. As you pointed out it's the multicast traffic from the source multicast server that's of interest. In reading what I found, if the switch has no information in it's CAM for the multicast group and the source multicast server begins sending multicast traffic, it hits the switch and does a lookup for the GDA, when it's not found the traffic is flooded out all ports in the VLAN. > > The question is not about basic IGMP and CGMP behavior. The question has to > do with switch behavior in the special case where the source of the > multicast traffic is on the same switch and in the same VLAN as the > recipients. We're concerned because that sounds like it would cause normal > multicast flooding to kick in. For that not to happen, the switch must be > smarter than we're thinking. Unfortunately, the switch even with CGMP isn't that smart. The flooding of the multicast traffic would continue until a host, any host on that VLAN sends a IGMP report to the router. The router then create the CGMP packet that will inform the switch of which ports will receive the multicast traffic. All other ports would be blocked except thee router ports. > >However, any futher > >attempts to join that existing group would then be limited to port listed in > >the CAM table that are eligible to recieve the multicast traffic for the > >group. > > Once again we're not talking about the membership reports (joins), although > what you say is probably true. > > I wonder if what's also true is that the first membership report causes the > switch to then not forward the server's multicast traffic to any devices > not listed in the port list in the CAM table for the multicast address. > That would make sense. Devices have to send their joins in order to get on > the list and get the traffic. Here's the reason for why the IGMP joins are instrumental to this process.. Multicast packets, coming from the source, don't trigger the router to send CGMP self-joins to the switch. > > Chptr 14, pgs 412-442 of Beau Williamson's book Developing IP > >Multicast Network provides some really good info on this issue. > > I couldn't find an answer to our question. Maybe you could?? Thanks. > > And to add to the question I've been wondering about more ordinary > multicasts, like OSPF Hellos and even BPDUs. If you enabled CGMP, would > these not get sent to any devices that didn't implement IGMP and sent their > membership report? That seems kind of ugly. Maybe it's not an issue because > you would only use CGMP on the edge in switches that connect end devices. I think the difference here is as someone posted earlier which defines the multicast well known MAC address as 0x0100.0cdd.. Also, with respect to IGMP capable host, they use the multicast address 224.0.0.2(AllRouter Mcast group) to send their leave messages. Of course this mechanism is that of IGMPv2, since under IGMPv1 there i
Re: multicast / CGMP towards the multicast server [7:33964]
Michael, CGMP does not have a concept of the multicast source (unlike the multicast routing protocol) and therefore the fact that the source is on the same link as the router should not change standard CGMP operation -- associating the CAM table with the various multicast groups. - Tom In article , "Fears Michael S SSgt 50 CS/SCBBN" wrote: > If a multicast server is connected to a Cisco Switch running CGMP, and > several hosts are connected to the same switch, will a router turn off > the switch ports for the users that are not requesting the multicast? > > So, will CGMP work back towards the multicast server? > > Fears > misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=34371&t=33964 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast Helper
I have lots of broadcast distributed with helper addresses. In order to reduce this I want to try IP multicast helper as documented by Cisco. http://www.cisco.com/warp/public/cc/techno/tity/ipmu/prodlit/helpr_an.htm Anyone have any experiense whith this type of setup? Jon Harald Bovre _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast Addressing
I'm reading through McGraw Hill's BUMS book. Chapter 7 deals with IP = Multicast Addressing. I understand that class D addresses are used = (high order bits set to 1110), but a statement used in the book confuses = me: IP Multicast addresses start with 224.0.0.0 and end with 239.255.255.255 I'm not real keen on where the 239 came from... Thanks All !!! Phil=20 _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast through firewall
Hi I am trying to pass a muticast stream (IPTV) through a pix firewall. The PIX firewall seems to be blocking it. Anyway of defining a ruleset on the firewall for muticast. I am using PIM DM for muticast routing. I have the option of replacing the PIX with check point. Any help will be appreciated Regards Gautam _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
mega multicast question
Take these 3 pairs DR VICE RP SPARSE VICE DENSE SHARED VICE SOURCE TREE make the 3 sqared=9 possibilities, such as: Explain what the Designated Router does when sparse mode on a shared Tree? Explain what the DR does in dense mode on a source tree? Explain what the RP does in dense mode on a shared tree? etc. after this i guess multicast would no longer be confusing _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
OSPF multicast addresses
Hi everyone, I am trying to figure out in which situations certain OSPF multicast addresses are used. The two multicast addresses used in OSPF that I know of are 224.0.0.5 and 224.0.0.6. From my understanding, in a broadcast network, all ospf routers send link info to the DR/BDR with the address of 224.0.0.6. The DR will then send all the data back to the DROTHER routers using the address of 224.0.0.5. Is this correct? I previously thought that the DR sent the data back using the address of 224.0.0.6, but this wouldn't work because the DROTHER routers don't listen to that address. Is this also correct? _ Get your FREE download of MSN Explorer at http://explorer.msn.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
OSPF multicast addresses
Hi everyone, I am trying to figure out in which situations certain OSPF multicast addresses are used. The two multicast addresses used in OSPF that I know of are 224.0.0.5 and 224.0.0.6. From my understanding, in a broadcast network, all ospf routers send link info to the DR/BDR with the address of 224.0.0.6. The DR will then send all the data back to the DROTHER routers using the address of 224.0.0.5. Is this correct? I previously thought that the DR sent the data back using the address of 224.0.0.6, but this wouldn't work because the DROTHER routers don't listen to that address. Is this also correct? Thanks in advance, Fred _ Get your FREE download of MSN Explorer at http://explorer.msn.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast Group Join???
I'm studying CCNP Switching and am hung-up on a part of multicast. Multicast works by a client sending a membership report that it wants to join a particular multicast group. I do not understand how the client knows about the existence of any particular group or what it's multicast address would be, or what application/service the client will receive as a part of that group. How does a client know enough about the group to want to join the group. I understand the layer 3 and layer 2 of it all, but I'm having a disconnect as to how it all interacts with the higher levels of the stack. Thank You, Mike B. _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast and BCSMN
Hello: How deep do you see Multicast in BCSMN classes ? Does BCSMN study provide strong enough knowledge in Multicast ? Thanks, Billy _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
multicast or unicast?
i am confused on communication type of ospf point-to-multipoint network packet . 2 descriptions from jeff dolye's routing tcp/ip vol1 are as follow: page417,2nd paragragh routers on these networks(point-to-multipoint networks) do not elect a dr and bdr , and because the networks are seen as point-to-point links, the ospf packets are multicast. ~~ page451,4th paragragh on point-to-multipoint and virtual link networks,updates(link state update) are unicasted to the interface addresses of the ~ adjacent neighbors. which one is correct? or both? thanks in advance. -- Regards, Zhao Meng. CCNA,MCSE,MCP+I _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast [7:14630]
In the BCMSN are you required to map multicast IP addresses to multicast MAC addresses and if so does anyone know a quick way of converting from binary to hex. Mike __ Disclaimer and confidentiality note Everything in this e-mail and any attachments relating to the official business of Standard Bank Investment Corporation (Stanbic) is proprietary to the company. It is confidential, legally privileged and protected by law.\ Stanbic does not own and endorse any other content. Views and opinions are those of the sender unless clearly stated as being that of Stanbic. The person addressed in the e-mail is the sole authorised recipient. Please notify the sender immediately if it has unintentionally reached you and do not read, disclose or use the content in any way. Stanbic can not assure that the integrity of this communication has been maintained nor that it is free of errors, virus, interception or interference. __ Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=14630&t=14630 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
TR supports multicast !!
Hello group, About my last question: Does the Token Ring (IEEE 802.5) support Multicasts (sending packets to a group of devices) .. I have two answre saying yes, i have asked an CCIE .. he told me: TR does not do multicast, IBM or IEEE. It does use functional addresses kinda like multicast, butthere's a verylimited set of these. IOS doc from Cisco on HSRP on Token Ring has some related material. Now i have 2 answers .. any one can help .. Thanks Mohammed Hakim - CCNA
Re: multicast address
Please BCMSN from cisco press, it explain how to convert the address... Subramanian Nallasivam ¼¶¼g©ó¤å³¹ <[EMAIL PROTECTED]>... >Hi, > > Can somebody explain me how to convert an multicast IP address >for e.g (224.0.0.6) into multicast mac address. > >TIA, >-Subbi. > > >___ >UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html >FAQ, list archives, and subscription info: http://www.groupstudy.com >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast [7:66831]
I need a little information about, multicast, if I am using multicast within a single IP network can I use the cisco 2950 switches, i.e. do I need any multicast protocolls such as IGMP and the like. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66831&t=66831 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
multicast [7:47591]
At what OSI layer do IP multicasts lie? Reading through CCO has made me more doubtful in my choices. TIA Robert Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47591&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast [7:57773]
Hi, I have some users who want to use a multicast application between different vlans. Is multicast forwarding turned on by default on 12.1 IOS? Would'nt I need to config something like PIM, IGMP and CGMP on my cat's and routers to do this efficiently or will the IOS just flood multicast packets out all interfaces by default? Thanks for any clues! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=57773&t=57773 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast Problem : Cat6509- MSFC
Hi all Currently we are using Cat6500, MSFC 1 running on "IOS MSFC Software (C6MSFC-IS-M), Version 12.1(4)E1" We have ip multicast group streaming video across the subnets (10 IP subnet). We have seen frame dropping whenever a new user join or exit the multicast group. Before the Cat6509 with MSFC, we were using Cat5500 with RSM running version "IOS (tm) C5RSM Software (C5RSM-ISV-M), Version 12.1(4)" and we have not seen this problem before. Anyone can advise ? _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
FW: IP Multicast Addressing
I'm just a little CCNA, I don't know what IP multicasting is (yet!), but I believe class E networks have 4 higher order bits set to 1, ie 240 - which explains why Class D's end at 239.255.255.255 (I think!) -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Circusnuts Sent: 10 February 2001 16:43 To: [EMAIL PROTECTED] Subject: IP Multicast Addressing I'm reading through McGraw Hill's BUMS book. Chapter 7 deals with IP = Multicast Addressing. I understand that class D addresses are used = (high order bits set to 1110), but a statement used in the book confuses = me: IP Multicast addresses start with 224.0.0.0 and end with 239.255.255.255 I'm not real keen on where the 239 came from... Thanks All !!! Phil=20 _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: IP Multicast Addressing
Class D's have 1110 (which add up to 224) being the high order bits. You may be onto something... but how would you explaining the 239.255.255.255 subnet mask. This is where I drop into the "hu" faze. Thanks Tim Phil - Original Message - From: "Tim" <[EMAIL PROTECTED]> To: "Circusnuts" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Saturday, February 10, 2001 6:20 PM Subject: RE: IP Multicast Addressing > I'm just a little CCNA, I don't know what IP multicasting is, > but I believe class E networks have 4 higher order bits set to 1, > ie 240 - which explains why Class D's end at 239.255.255.255 > > (I think!) > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > Circusnuts > Sent: 10 February 2001 16:43 > To: [EMAIL PROTECTED] > Subject: IP Multicast Addressing > > > I'm reading through McGraw Hill's BUMS book. Chapter 7 deals with IP = > Multicast Addressing. I understand that class D addresses are used = > (high order bits set to 1110), but a statement used in the book confuses = > me: > > IP Multicast addresses start with 224.0.0.0 and end with 239.255.255.255 > > I'm not real keen on where the 239 came from... > > Thanks All !!! > Phil=20 > > _ > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: IP Multicast Addressing
The 239.255.255.255 is the highest in that subnet. D class starts at 224 (1110) and then E class would start at 240 (). This makes the D class range of addresses: 224.0.0.0 through 239.255.255.255. Therefor if D class addresses are used for multicasting then the 239.255.255.255 address would be the last address in that range before falling into an E class address. Here are the ranges: A = 1.0.0.0 - 127.255.255.255 B = 128.0.0.0 - 191.255.255.255 C = 192.0.0.0 - 123.255.255.255 D = 224.0.0.0 - 239.255.255.255 << Here is the multicast range (I believe) E = 240.0.0.0 - 247.255.255.255 Hope I helped (and was right) =o) Mark Z... In a message dated 2/10/01 4:56:54 PM Eastern Standard Time, [EMAIL PROTECTED] writes: > Class D's have 1110 (which add up to 224) being the high order bits. You > may be onto something... but how would you explaining the 239.255.255.255 > subnet mask. This is where I drop into the "hu" faze. > > Thanks Tim > Phil > > - Original Message - > From: "Tim" <[EMAIL PROTECTED]> > To: "Circusnuts" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> > Sent: Saturday, February 10, 2001 6:20 PM > Subject: RE: IP Multicast Addressing > > > > I'm just a little CCNA, I don't know what IP multicasting is, > > but I believe class E networks have 4 higher order bits set to 1, > > ie 240 - which explains why Class D's end at 239.255.255.255 > > > > (I think!) > > > > -Original Message- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > > Circusnuts > > Sent: 10 February 2001 16:43 > > To: [EMAIL PROTECTED] > > Subject: IP Multicast Addressing > > > > > > I'm reading through McGraw Hill's BUMS book. Chapter 7 deals with IP = > > Multicast Addressing. I understand that class D addresses are used = > > (high order bits set to 1110), but a statement used in the book confuses = > > me: > > > > IP Multicast addresses start with 224.0.0.0 and end with 239.255.255.255 > > > > I'm not real keen on where the 239 came from... > > > > Thanks All !!! > > Phil=20 > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: IP Multicast Addressing
Phil, It has to do with the hight order bit. Look at the address space in binary. The range 224.0.0.0 - 239.255.255.255 becomes: 1100... through 1101... If you add that one bit so that the first octet becomes 1110 then you have moved past this boundry to become a class E address. Brian Circusnuts wrote: > I'm reading through McGraw Hill's BUMS book. Chapter 7 deals with IP = > Multicast Addressing. I understand that class D addresses are used = > (high order bits set to 1110), but a statement used in the book confuses = > me: > > IP Multicast addresses start with 224.0.0.0 and end with 239.255.255.255 > > I'm not real keen on where the 239 came from... > > Thanks All !!! > Phil=20 > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: IP Multicast Addressing
Yepper's- makes total sense... I saw is as a subnet mask @ first glance. Thanks Phil - Original Message - From: "Brian Keyser" <[EMAIL PROTECTED]> To: "Circusnuts" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Sunday, February 11, 2001 3:29 PM Subject: Re: IP Multicast Addressing > Phil, > It has to do with the hight order bit. Look at the address space in binary. > > The range 224.0.0.0 - 239.255.255.255 becomes: > > 1100... through > 1101... > > If you add that one bit so that the first octet becomes 1110 then you > have moved past this boundry to become a class E address. > > Brian > > Circusnuts wrote: > > > I'm reading through McGraw Hill's BUMS book. Chapter 7 deals with IP = > > Multicast Addressing. I understand that class D addresses are used = > > (high order bits set to 1110), but a statement used in the book confuses = > > me: > > > > IP Multicast addresses start with 224.0.0.0 and end with 239.255.255.255 > > > > I'm not real keen on where the 239 came from... > > > > Thanks All !!! > > Phil=20 > > > > _ > > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > > > > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: OSPF multicast addresses
yes, this is correct -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Fred Danson Sent: Sunday, March 11, 2001 8:56 PM To: [EMAIL PROTECTED] Subject: OSPF multicast addresses Hi everyone, I am trying to figure out in which situations certain OSPF multicast addresses are used. The two multicast addresses used in OSPF that I know of are 224.0.0.5 and 224.0.0.6. From my understanding, in a broadcast network, all ospf routers send link info to the DR/BDR with the address of 224.0.0.6. The DR will then send all the data back to the DROTHER routers using the address of 224.0.0.5. Is this correct? I previously thought that the DR sent the data back using the address of 224.0.0.6, but this wouldn't work because the DROTHER routers don't listen to that address. Is this also correct? _ Get your FREE download of MSN Explorer at http://explorer.msn.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: OSPF multicast addresses
you are right. 5 is used in the beginning at exchange process. During maint. it is as you described. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Fred Danson Sent: Monday, March 12, 2001 12:59 AM To: [EMAIL PROTECTED] Subject: OSPF multicast addresses Hi everyone, I am trying to figure out in which situations certain OSPF multicast addresses are used. The two multicast addresses used in OSPF that I know of are 224.0.0.5 and 224.0.0.6. From my understanding, in a broadcast network, all ospf routers send link info to the DR/BDR with the address of 224.0.0.6. The DR will then send all the data back to the DROTHER routers using the address of 224.0.0.5. Is this correct? I previously thought that the DR sent the data back using the address of 224.0.0.6, but this wouldn't work because the DROTHER routers don't listen to that address. Is this also correct? Thanks in advance, Fred _ Get your FREE download of MSN Explorer at http://explorer.msn.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Fw: multicast or unicast?
I think if asked it would be a multicast. Ran into a problem with updates dropping of because of a misconfig on a switch that was blocking multicasts. If Im wrong someone please correct me :) L Morgan Redd, CCNA - Original Message - > > From: "Zhao Meng" <[EMAIL PROTECTED]> > > Newsgroups: groupstudy.cisco > > To: <[EMAIL PROTECTED]> > > Sent: Sunday, November 19, 2000 4:01 AM > > Subject: multicast or unicast? > > > > > > > i am confused on communication type of ospf point-to-multipoint network > > > packet . > > > > > > 2 descriptions from jeff dolye's routing tcp/ip vol1 are as follow: > > > > > > page417,2nd paragragh > > > routers on these networks(point-to-multipoint networks) do not > > > elect a dr and bdr , and because the networks are seen as > > > point-to-point links, the ospf packets are multicast. > > >~~ > > > page451,4th paragragh > > > on point-to-multipoint and virtual link networks,updates(link > > > state update) are unicasted to the interface addresses of the > > > ~ > > > adjacent neighbors. > > > > > > which one is correct? or both? > > > > > > thanks in advance. > > > > > > -- > > > Regards, > > > Zhao Meng. > > > CCNA,MCSE,MCP+I > > > > > > > > > _ > > > FAQ, list archives, and subscription info: > > http://www.groupstudy.com/list/cisco.html > > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > > > > > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast Group Join???
Applications usually have a default/well-known multicast group address they use. This may be configurable depending on the app. Similar to port numbers, most people use the defaults (80 for http, 23 for telnet, etc) but some people change them. If someone changes the multicast group address from the default then it is up to them to let people know what the multicast group address is and how to change it in the application. --- Mike Balistreri <[EMAIL PROTECTED]> wrote: > > I'm studying CCNP Switching and am hung-up on a part > of multicast. > > Multicast works by a client sending a membership > report that it wants to > join a particular multicast group. > > I do not understand how the client knows about the > existence of any > particular group or what it's multicast address > would be, or what > application/service the client will receive as a > part of that group. > How does a client know enough about the group to > want to join the group. > > I understand the layer 3 and layer 2 of it all, but > I'm having a > disconnect as to how it all interacts with the > higher levels of the > stack. > > Thank You, > > > Mike B. > > > > _ > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] __ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast Group Join???
It is driven by the application. The application decides it wants to work by multicasting packets or receiving multicast packets, so it reports it wants to join multicast group X where X is a multicast IP that was either coded into it, or configured by the user. If you have two users with the same application, but they enter different multicast IPs to use, they won't be able to talk because they will be in different groups. - Original Message - From: "Mike Balistreri" <[EMAIL PROTECTED]> Newsgroups: groupstudy.cisco To: <[EMAIL PROTECTED]> Sent: Thursday, January 18, 2001 10:35 PM Subject: Multicast Group Join??? > > I'm studying CCNP Switching and am hung-up on a part of multicast. > > Multicast works by a client sending a membership report that it wants to > join a particular multicast group. > > I do not understand how the client knows about the existence of any > particular group or what it's multicast address would be, or what > application/service the client will receive as a part of that group. > How does a client know enough about the group to want to join the group. > > I understand the layer 3 and layer 2 of it all, but I'm having a > disconnect as to how it all interacts with the higher levels of the > stack. > > Thank You, > > > Mike B. > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast and BCSMN
On Fri, 13 Oct 2000, Billy Monroe wrote: > Hello: > > How deep do you see Multicast in BCSMN classes ? not too deep imho, I posted about how deep its in the archives. > Does BCSMN study provide strong enough knowledge in Multicast ? yes.generally the classes always cover enough for at least the test. > Thanks, > > Billy > > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > --- Brian Feeny, CCNP, CCDP [EMAIL PROTECTED] Network Administrator ShreveNet Inc. (ASN 11881) _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Multicast and BCSMN
I just took the BCMSN exam today and it was very light on multicasting. They had some basic questions on the nature of multicasts, IP/MAC conversion, CGMP, and maybe one or two on IGMP and PIM. Nothing about Auto-RP, DVMRP, not even anything on sparse or dense mode and distribution trees. I did feel like the Karen Webb book, in conjunction with the couple routers I have here at my home lab, gave me a pretty good understanding of how multicast works and the basics of using PIM. As with all else though, I'm sure real-world experience does more good than anything; I've never worked with actual multicast applications and streams. Hope that helps, good luck. ~Seth~ > Hello: > > How deep do you see Multicast in BCSMN classes ? > Does BCSMN study provide strong enough knowledge in Multicast ? > > Thanks, > > Billy _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast or unicast?
You may be confusing multi-point with broadcast. Zhao Meng wrote: > i am confused on communication type of ospf point-to-multipoint network > packet . > > 2 descriptions from jeff dolye's routing tcp/ip vol1 are as follow: > > page417,2nd paragragh > routers on these networks(point-to-multipoint networks) do not > elect a dr and bdr , and because the networks are seen as > point-to-point links, the ospf packets are multicast. >~~ > page451,4th paragragh > on point-to-multipoint and virtual link networks,updates(link > state update) are unicasted to the interface addresses of the > ~ > adjacent neighbors. > > which one is correct? or both? > > thanks in advance. > > -- > Regards, > Zhao Meng. > CCNA,MCSE,MCP+I > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Stop multicast to router
Hi all, I have been presented a problem I'm not sure of the answer. I have a CAT5000 switch connecting several VLAN's and a Cisco2948 providing routing/switching. One of the VLAN's has a process that uses a multicasts. These multicasts cause the Cisco2948 a little grief. I do not want the Cisco2980 to see the multicast traffic. Any clues would be appreciated. Teunis Hobart, Tasmania Australia -- www.tasmail.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Ethernet multicast [7:10272]
1) Does a Network Interface card support 2^47 ethernet multicast address.If so how are the Addresses generated or stored? 2)How are the Ip Multicast address mapped to Ethernet multicast address? Cheers Get 250 color business cards for FREE! http://businesscards.lycos.com/vp/fastpath/ Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=10272&t=10272 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast Question [7:39732]
Guys, Need your help to clear some concept. Suppose we have 4 routers ,we want to configure 3 of them as a PIM SParse mode and one as a Dense mode.Can they communicate with each other??I meant can they transfer multicasting info to each other. or we must have to use PIM SPARSE DENSE mode on all routers?? Thkx for help. TOM _ MSN Photos is the easiest way to share and print your photos: http://photos.msn.com/support/worldwide.aspx Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=39732&t=39732 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
multicast+qos [7:40155]
Hi, Can someone let me know the multicast+qos exam prep book for CCIP. Let me know the ISBN No. Kind Regards /Thangavel -- CCIE (qual),CCS,CCDP,CCNP,MCSE 186K Reading,Brkshire Direct No -0118 9064259 Mobile No -07796292416 Post code: RG16LH www.186k.co.uk -- The greatest glory in living lies not in never falling, but in rising every time we fall ." -- Nelson Mandela ** This e-mail is from 186k Ltd and is intended only for the addressee named above. As this e-mail may contain confidential or priveleged information, if you are not the named addressee or the person responsible for delivering the message to the named addressee, please advise the sender by return e-mail. The contents should not be disclosed to any other person nor copies taken. 186k Ltd is a Lattice Group company, registered in England & Wales No. 3751494 Registered Office 130 Jermyn Street London SW1Y 4UR ** Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=40155&t=40155 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: TR supports multicast !!
The CCIE is right :) ... In fact there is no specification of multicast addresses in Token Ring and they ARE implemented with what they call Functional Addresses. Regards Atif -Original Message-From: Mohammed Hakim <[EMAIL PROTECTED]>To: [EMAIL PROTECTED] <[EMAIL PROTECTED]>Date: Sunday, July 30, 2000 3:39 AMSubject: TR supports multicast !! Hello group, About my last question: Does the Token Ring (IEEE 802.5) support Multicasts (sending packets to a group of devices) .. I have two answre saying yes, i have asked an CCIE .. he told me: TR does not do multicast, IBM or IEEE. It does use functional addresses kinda like multicast, butthere's a verylimited set of these. IOS doc from Cisco on HSRP on Token Ring has some related material. Now i have 2 answers .. any one can help .. Thanks Mohammed Hakim - CCNA
RE: Multicast [7:66831]
Skarphedinsson Arni V. wrote: > > I need a little information about, multicast, if I am using > multicast within a single IP network can I use the cisco 2950 > switches, i.e. do I need any multicast protocolls such as IGMP > and the like. IGMP lets a router know that there are devices on one of its segments that need to get a particular IP multicast flow. If you don't have routers, you don't need IGMP. Switches by default flood multicasts out every port. You can constrain this with VLANs, so you would want to know about any VLANs in use on your switched network. But, in general, multicast just works on a switched network. There may be specific applications that wouldn't work due to brain-damaged implementions (that depend on IGMP regardless or something), but theoretically you shouldn't have a problem. Priscilla Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=66862&t=66831 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast server [7:69686]
Has anyone got any Multicast server software for windows NT I would like to get some multicast traffic working on my testlab thanks Ian Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=69686&t=69686 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast [7:47591]
I'm going to say the addresses are L3, udp used as transport is L4, and the apps are L7, with some of the formats such as MPeg2 L6. ""Lopez, Robert"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > At what OSI layer do IP multicasts lie? Reading through CCO has made me > more doubtful in my choices. > > TIA > > Robert Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47593&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: multicast [7:47591]
Robert, Layer 3 is where multicasting takes place. Raul -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Lopez, Robert Sent: Thursday, June 27, 2002 4:42 PM To: [EMAIL PROTECTED] Subject: multicast [7:47591] At what OSI layer do IP multicasts lie? Reading through CCO has made me more doubtful in my choices. TIA Robert Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47595&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast [7:47591]
At 04:42 PM 6/27/02, Lopez, Robert wrote: >At what OSI layer do IP multicasts lie? Reading through CCO has made me >more doubtful in my choices. IP multicasts are sent to a layer 3 IP multicast address. That address is converted to a data-link-layer multicast address. The Internet Assigned Numbers Authority (IANA) owns a block of MAC-layer addresses that are used for group multicast addresses. The range of addresses for Ethernet is 0x01:00:5E:00:00:00 through 0x01:00:5E:7F:FF:FF. When a host sends a frame to an IP group that is identified by a Class D address, the host inserts the low-order 23 bits of the Class D address into the low-order 23 bits of the MAC-layer destination address. The top 9 bits of the Class D address are not used. The top 25 bits of the MAC address are 0x01:00:5E followed by a zero bit (0001 0100 0 in binary). IP multicast gets used for many purposes and those purposes may be at different layers: Sending routing updates (EIGRP, OSPF, RIPv2) - Layer 3 Establishing routing protocol neighbor relationships (EIGRP, OSPF) - Layer 3 Sending multimedia streaming audio or video - Layer 7 with some help from Layer 6 (MPEG or whatever), Layer 5 (RTSP), and Layer 4 (UDP) Finding services (Service Location Protocol) - Layer 7 Joining groups (IGMP) - Layer 3 Determining a dynamic L3 address assignment (IPv6) - Layer 3 There's probably lots of others too! Layer 2 multicasts are used for IP multicast, but for many other purposes too, such as BPDU, CDP, VTP, DISL, AppleTalk Name Binding Protocol (NBP) lookups, etc. Priscilla >TIA > >Robert Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47601&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast [7:47591]
At 6:36 PM -0400 6/27/02, Priscilla Oppenheimer wrote: >At 04:42 PM 6/27/02, Lopez, Robert wrote: >>At what OSI layer do IP multicasts lie? Reading through CCO has made me >>more doubtful in my choices. > >IP multicasts are sent to a layer 3 IP multicast address. That address is >converted to a data-link-layer multicast address. The Internet Assigned >Numbers Authority (IANA) owns a block of MAC-layer addresses that are used >for group multicast addresses. The range of addresses for Ethernet is >0x01:00:5E:00:00:00 through 0x01:00:5E:7F:FF:FF. When a host sends a frame >to an IP group that is identified by a Class D address, the host inserts >the low-order 23 bits of the Class D address into the low-order 23 bits of >the MAC-layer destination address. The top 9 bits of the Class D address >are not used. The top 25 bits of the MAC address are 0x01:00:5E followed by >a zero bit (0001 0100 0 in binary). > >IP multicast gets used for many purposes and those purposes may be at >different layers: > >Sending routing updates (EIGRP, OSPF, RIPv2) - Layer 3 >Establishing routing protocol neighbor relationships (EIGRP, OSPF) - Layer 3 >Sending multimedia streaming audio or video - Layer 7 with some help from >Layer 6 (MPEG or whatever), Layer 5 (RTSP), and Layer 4 (UDP) >Finding services (Service Location Protocol) - Layer 7 >Joining groups (IGMP) - Layer 3 >Determining a dynamic L3 address assignment (IPv6) - Layer 3 You're not saying, are you, that IP multicast exists at layers above 3, are you? I think it is correct to say that a higher-layer protocol may assume that a lower-layer protocol will require use of a layer 3 multicast service, but doesn't itself implement multicast. The upper layer entity (in strict OSI terms) need not have direct access to the multicast network layer service, but potentially could indirectly request that functionality through higher-layer service interfaces. Without looking at the Transport Service Specification, I can't remember if it has the semantics, with the Connectionless Transport Service, of multicasts. My general recollection is that you use a network service address and let the Network Service figure out the semantics. > >There's probably lots of others too! > >Layer 2 multicasts are used for IP multicast, but for many other purposes >too, such as BPDU, CDP, VTP, DISL, AppleTalk Name Binding Protocol (NBP) >lookups, etc. > >Priscilla > > >>TIA >> >>Robert > > >Priscilla Oppenheimer >http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47624&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast [7:47591]
Did you copy/paste that right out of a textbook? =) Before I even saw anything indicating that you authored that post, I got about 1/2 way through the paragraph and was thinking to myself "This had to be from Priscilla". Mike W. "Priscilla Oppenheimer" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > At 04:42 PM 6/27/02, Lopez, Robert wrote: > >At what OSI layer do IP multicasts lie? Reading through CCO has made me > >more doubtful in my choices. > > IP multicasts are sent to a layer 3 IP multicast address. That address is > converted to a data-link-layer multicast address. The Internet Assigned > Numbers Authority (IANA) owns a block of MAC-layer addresses that are used > for group multicast addresses. The range of addresses for Ethernet is > 0x01:00:5E:00:00:00 through 0x01:00:5E:7F:FF:FF. When a host sends a frame > to an IP group that is identified by a Class D address, the host inserts > the low-order 23 bits of the Class D address into the low-order 23 bits of > the MAC-layer destination address. The top 9 bits of the Class D address > are not used. The top 25 bits of the MAC address are 0x01:00:5E followed by > a zero bit (0001 0100 0 in binary). > > IP multicast gets used for many purposes and those purposes may be at > different layers: > > Sending routing updates (EIGRP, OSPF, RIPv2) - Layer 3 > Establishing routing protocol neighbor relationships (EIGRP, OSPF) - Layer 3 > Sending multimedia streaming audio or video - Layer 7 with some help from > Layer 6 (MPEG or whatever), Layer 5 (RTSP), and Layer 4 (UDP) > Finding services (Service Location Protocol) - Layer 7 > Joining groups (IGMP) - Layer 3 > Determining a dynamic L3 address assignment (IPv6) - Layer 3 > > There's probably lots of others too! > > Layer 2 multicasts are used for IP multicast, but for many other purposes > too, such as BPDU, CDP, VTP, DISL, AppleTalk Name Binding Protocol (NBP) > lookups, etc. > > Priscilla > > > >TIA > > > >Robert > > > Priscilla Oppenheimer > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47627&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: multicast [7:47591]
A thanks to everyone who replied to this topic... -Original Message- From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] Sent: Thursday, June 27, 2002 6:36 PM To: [EMAIL PROTECTED] Subject: Re: multicast [7:47591] At 04:42 PM 6/27/02, Lopez, Robert wrote: >At what OSI layer do IP multicasts lie? Reading through CCO has made me >more doubtful in my choices. IP multicasts are sent to a layer 3 IP multicast address. That address is converted to a data-link-layer multicast address. The Internet Assigned Numbers Authority (IANA) owns a block of MAC-layer addresses that are used for group multicast addresses. The range of addresses for Ethernet is 0x01:00:5E:00:00:00 through 0x01:00:5E:7F:FF:FF. When a host sends a frame to an IP group that is identified by a Class D address, the host inserts the low-order 23 bits of the Class D address into the low-order 23 bits of the MAC-layer destination address. The top 9 bits of the Class D address are not used. The top 25 bits of the MAC address are 0x01:00:5E followed by a zero bit (0001 0100 0 in binary). IP multicast gets used for many purposes and those purposes may be at different layers: Sending routing updates (EIGRP, OSPF, RIPv2) - Layer 3 Establishing routing protocol neighbor relationships (EIGRP, OSPF) - Layer 3 Sending multimedia streaming audio or video - Layer 7 with some help from Layer 6 (MPEG or whatever), Layer 5 (RTSP), and Layer 4 (UDP) Finding services (Service Location Protocol) - Layer 7 Joining groups (IGMP) - Layer 3 Determining a dynamic L3 address assignment (IPv6) - Layer 3 There's probably lots of others too! Layer 2 multicasts are used for IP multicast, but for many other purposes too, such as BPDU, CDP, VTP, DISL, AppleTalk Name Binding Protocol (NBP) lookups, etc. Priscilla >TIA > >Robert Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47629&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: multicast [7:47591]
At 10:14 PM 6/27/02, Howard C. Berkowitz wrote: > >IP multicast gets used for many purposes and those purposes may be at > >different layers: > > > >Sending routing updates (EIGRP, OSPF, RIPv2) - Layer 3 > >Establishing routing protocol neighbor relationships (EIGRP, OSPF) - Layer 3 > >Sending multimedia streaming audio or video - Layer 7 with some help from > >Layer 6 (MPEG or whatever), Layer 5 (RTSP), and Layer 4 (UDP) > >Finding services (Service Location Protocol) - Layer 7 > >Joining groups (IGMP) - Layer 3 > >Determining a dynamic L3 address assignment (IPv6) - Layer 3 > > >You're not saying, are you, that IP multicast exists at layers above >3, are you? No, I said it's used by upper layers. Those layers are aware of it, though. The Service Location Protocol (SLP) RFC, for example, states which IP multicast address to use. The Realtime Streaming Protocol (RTSP) knows about IP multicast too. I don't know the details, but RTSP specifies a method for a client to find out what IP multicast address a server is sending to. There's a presentation description that includes the multicast address. If you look at the RFC for RTSP, there's lots of discussion of multicast. RTSP is nominally an application-layer protocol, at least according to the author of the RFC. Priscilla >I think it is correct to say that a higher-layer protocol >may assume that a lower-layer protocol will require use of a layer 3 >multicast service, but doesn't itself implement multicast. The upper >layer entity (in strict OSI terms) need not have direct access to the >multicast network layer service, but potentially could indirectly >request that functionality through higher-layer service interfaces. > >Without looking at the Transport Service Specification, I can't >remember if it has the semantics, with the Connectionless Transport >Service, of multicasts. My general recollection is that you use a >network service address and let the Network Service figure out the >semantics. > > > >There's probably lots of others too! > > > >Layer 2 multicasts are used for IP multicast, but for many other purposes > >too, such as BPDU, CDP, VTP, DISL, AppleTalk Name Binding Protocol (NBP) > >lookups, etc. > > > >Priscilla > > > > > >>TIA > >> > >>Robert > > > > > >Priscilla Oppenheimer > >http://www.priscilla.com Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47637&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: multicast [7:47591]
In regards to the OSI specs, is it safe to say that IP multicasts exist at layers 2 and 3? -Original Message- From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] Sent: Friday, June 28, 2002 1:15 AM To: [EMAIL PROTECTED] Subject: Re: multicast [7:47591] At 10:14 PM 6/27/02, Howard C. Berkowitz wrote: > >IP multicast gets used for many purposes and those purposes may be at > >different layers: > > > >Sending routing updates (EIGRP, OSPF, RIPv2) - Layer 3 > >Establishing routing protocol neighbor relationships (EIGRP, OSPF) - Layer 3 > >Sending multimedia streaming audio or video - Layer 7 with some help from > >Layer 6 (MPEG or whatever), Layer 5 (RTSP), and Layer 4 (UDP) > >Finding services (Service Location Protocol) - Layer 7 > >Joining groups (IGMP) - Layer 3 > >Determining a dynamic L3 address assignment (IPv6) - Layer 3 > > >You're not saying, are you, that IP multicast exists at layers above >3, are you? No, I said it's used by upper layers. Those layers are aware of it, though. The Service Location Protocol (SLP) RFC, for example, states which IP multicast address to use. The Realtime Streaming Protocol (RTSP) knows about IP multicast too. I don't know the details, but RTSP specifies a method for a client to find out what IP multicast address a server is sending to. There's a presentation description that includes the multicast address. If you look at the RFC for RTSP, there's lots of discussion of multicast. RTSP is nominally an application-layer protocol, at least according to the author of the RFC. Priscilla >I think it is correct to say that a higher-layer protocol >may assume that a lower-layer protocol will require use of a layer 3 >multicast service, but doesn't itself implement multicast. The upper >layer entity (in strict OSI terms) need not have direct access to the >multicast network layer service, but potentially could indirectly >request that functionality through higher-layer service interfaces. > >Without looking at the Transport Service Specification, I can't >remember if it has the semantics, with the Connectionless Transport >Service, of multicasts. My general recollection is that you use a >network service address and let the Network Service figure out the >semantics. > > > >There's probably lots of others too! > > > >Layer 2 multicasts are used for IP multicast, but for many other purposes > >too, such as BPDU, CDP, VTP, DISL, AppleTalk Name Binding Protocol (NBP) > >lookups, etc. > > > >Priscilla > > > > > >>TIA > >> > >>Robert > > > > > >Priscilla Oppenheimer > >http://www.priscilla.com Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47650&t=47591 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast labs [7:18816]
Dear ALL, Anyone would point out starting place to setup a multicast testing environment? HIA Fanglo Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=18816&t=18816 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast Problem [7:20604]
Hello guys, I am having a multicast problem for the past 3 days. When I go to my cat500 switcha and type: show multicast group, I can't see the mac address. I have 3 routers running dense mode and they are all connect to the cat switch in the same vlan.I am running multicast on the switch to Any help will be great: This is the config: R8 interface Loopback0 ip address 172.16.250.1 255.255.255.0 no ip directed-broadcast ip pim dense-mode ip igmp join-group 226.6.6.6 ! interface Ethernet0/0 ip address 172.16.23.3 255.255.255.0 no ip directed-broadcast ! interface Serial0/0 encapsulation frame-relay ! interface Serial0/0.1 point-to-point ip address 172.16.11.8 255.255.255.0 no ip directed-broadcast ip pim dense-mode frame-relay interface-dlci 802 ! interface Serial0/0.2 multipoint ip address 172.16.10.8 255.255.255.0 no ip directed-broadcast ip pim dense-mode ip ospf network point-to-multipoint frame-relay map ip 172.16.10.9 809 broadcast frame-relay map ip 172.16.10.12 812 broadcast ! router ospf 100 network 172.16.0.0 0.0.255.255 area 0 r12 ip multicast-routing ip dvmrp route-limit 2 ! interface Ethernet0 ip address 172.16.13.1 255.255.255.0 ip cgmp ! interface Serial0 ip address 172.16.10.12 255.255.255.0 ip pim dense-mode encapsulation frame-relay ip ospf network point-to-multipoint frame-relay map ip 172.16.10.8 128 broadcast frame-relay lmi-type cisco ! router ospf 100 network 172.16.0.0 0.0.255.255 area 0 r2 hostname r2 ! ip subnet-zero ! ip multicast-routing ip dvmrp route-limit 2 cns event-service server ! ! ! interface Ethernet0 ip address 172.16.13.2 255.255.255.0 ip pim dense-mode no ip route-cache ip cgmp no ip mroute-cache ! interface Serial0 ip address 172.16.11.2 255.255.255.0 ip pim dense-mode encapsulation frame-relay no ip route-cache ip ospf network point-to-multipoint no ip mroute-cache logging event subif-link-status logging event dlci-status-change frame-relay map ip 172.16.11.8 208 broadcast _ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=20604&t=20604 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast [7:20684]
Hi I am looking at getting IP Multicast working on my Core network and also access to the MBone. Can any of you please forward me towards any good books/white papers on how to do this. I passed BCMSN so have a fair under standing of the theory but 100% sure on how to make the connection from Local network to the rest of the world. I was looking at getting either :- Developing IP Multicast Networks by Beau Williamsonor Cisco Multicasting Routing & Switching by William R. Parkhurst Thanks in advance Andrew Andrew S. Twigger Networks Team Leader Firstnet Services Ltd Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=20684&t=20684 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast Flooding [7:22025]
Any one have an idea on how to suppress multicast flooding on a 2948G-L3. The switch is configured with 3 bridge groups, and 3 bvi interfaces. The problem is that multicast packets are flooded throughout the bridge group the multicast server is connected to. Below is a snippet of the running config: ip multicast-routing ip dvmrp route-limit 2 bridge irb ! int f1 no ip address bridge-group 2 ! int f2 no ip address bridge-group 2 ! int f3 no ip address bridge-group 3 ! int bvi 2 ip add 10.10.20.1 255.255.255.0 ip pim sparse-dense-mode ! int bvi 3 ip add 10.10.30.1 255.255.255.0 ip pim sparse-dense-mode ! bridge cmf bridge 2 proto ieee bridge 2 route ip bridge 3 proto ieee bridge 3 route ip etc Software version is: cat2948g-in-mz.120-14.W5.20.bin CGMP is not supported on the bvi interface (at least not with this software release). CMF (Constrained Multicast Flooding) should do the trick, but doesn't appear to be working as expected. The flooding happens regardless of whether or not any host registers interest in receiving the multicast group. Multicast routing is working fine, and only registered hosts receive the multicast traffic, i.e flooding does not occur on the bridge group that the multicast server is not connected to. Any ideas will be greatly appreciated. CM Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=22025&t=22025 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
eigrp multicast [7:23349]
hi all i meet a trouble, i connect two router through a catalyst switch. eigrp neighbor established very interestin. some time established and some time tear down. when i debug ip igsn in switch,i found igmp protocol create 0100.5e00.000a some time and delete 0100.5e00.000a,and other all groups also deleted and recreate at same time.when 0100.5e00.000a is deleted, eigrp neighbor can established ,and when 0100.5e00.000a is recreated ,eigrp can't established neighbor i type show mac static and i can see 0100.5e00.000a entry ,but link to another port which not belonged to link two router port. this is interesting,it seems a multicast workstation configed 225.0.0.10 or same like map to 0100.5e00.000a. but i don't know why the multicast group deleted all and recreated. and another question does eigrp multicast address 224.0.0.10 ospf 224.0.0.5 224.0.0.6 attend igmp multicast group? when i show mac static in my lab i can't see 0100.5e00.000a entry. i think such as 224.0.0.10 224.0.0.5 don't attend any multicast group ,and controlled by igmp,cgmp. is that right, when switch received a 224.0.0.10 packet,how about it transfer this packet when switch igmp snoop is enabled thank you i will find why igmp group is deleted and recreated. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=23349&t=23349 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast question [7:57774]
Hi, I have some users who want to use a multicast application between different vlans. Is multicast forwarding turned on by default on 12.1 IOS? Would'nt I need to config something like PIM, IGMP and CGMP on my cat's and routers to do this efficiently or will the IOS just flood multicast packets out all interfaces by default? Thanks for any clues! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=57774&t=57774 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Multicast [7:57773]
Yes, yes and yes but, only certain cats support igmp snooping. Timothy B. Fernandez Network Technician Sales, Trading and Wealth Management Thomson Financial [EMAIL PROTECTED] Phone: 630-353-7013 Fax: 630-435-4960 901 Warrenville Rd Suite 15 Lisle, IL 60532 -Original Message- From: Hotmail Cisco [mailto:[EMAIL PROTECTED]] Sent: Wednesday, November 20, 2002 9:54 AM To: [EMAIL PROTECTED] Subject: Multicast [7:57773] Hi, I have some users who want to use a multicast application between different vlans. Is multicast forwarding turned on by default on 12.1 IOS? Would'nt I need to config something like PIM, IGMP and CGMP on my cat's and routers to do this efficiently or will the IOS just flood multicast packets out all interfaces by default? Thanks for any clues! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=57788&t=57773 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
ip multicast [7:60813]
I need to break up this address for muticast group assignment. 239.0.0.0/8 what would be the best way to break these up for different groups. [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=60813&t=60813 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
multicast address [7:50221]
Where can I find the multicast address , rip, irgp use.? I know Ospf is 224.0.5 & 224.0.6 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=50221&t=50221 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast scenario [7:50994]
What type of server would be good to set up a multicast scenario and test it out.? Apple server streaming video, or a advance 2000 server. What have you done. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=50994&t=50994 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast. [7:51648]
Hello Group. Does anybody know where can I find a complete information about the IP Multicast tecnoloy? Thanks. _ Join the worlds largest e-mail service with MSN Hotmail. http://www.hotmail.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=51648&t=51648 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Multicast [7:53412]
Hi, If you have control over the TTL of the multicast packets, you can make use of the TTL threshold interface command (ip multicast ttl-threshold). For instance, set a threshold of 15 on Serial0/3. Multicast packets with a TTL lower than 15, will not be forwarded out that interface. Now ensure that packets that DO need to be forwarded out that interface, have a TTL of more than 15 when they arrive at your router. Regards Jaco -Original Message- From: router poon [mailto:[EMAIL PROTECTED]] Sent: Monday, September 16, 2002 5:37 PM To: [EMAIL PROTECTED] Subject: Multicast [7:53412] Hi, I have question on the multicast. Serial0/2 is sending the multicast to Ethernet0/0 and Serial0/3. How can I block the multicast traffic sending to Serial0/3 and only send to Ethernet0/0. I cannot tun off the "ip pim dense-mode" command because there is another multicast traffic sending from Serial0/3 to Ethernet0/0. Any Hints. (*, 224.0.24.10), 00:46:39/00:00:00, RP 0.0.0.0, flags: DJCL Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Serial0/3, Forward/Dense, 00:46:39/00:00:00 Serial0/2, Forward/Dense, 00:46:39/00:00:00 Ethernet0/0, Forward/Dense, 00:46:39/00:00:00 (10.1.1.2, 224.0.24.10), 00:46:39/00:02:59, flags: CLTA Incoming interface: Serial0/2, RPF nbr 11.1.1.2 Outgoing interface list: Serial0/3, Forward/Dense, 00:46:39/00:00:00 Ethernet0/0, Forward/Dense, 00:46:39/00:00:00 03:11:49: IP: s=10.1.1.1 (Serial0/2) d=224.0.24.10 (Serial0/3) len 532, mforward 03:11:49: IP: s=10.1.1.1 (Serial0/2) d=224.0.24.10 (Ethernet0/0) len 532, mforward Thanks. - Do you Yahoo!? Yahoo! News - Today's headlines Give your child an unfair advantage with M-Web Learning. To join, call 08600 32 000 or go to http://join.mweb.co.za M-Web JUST LIKE THAT Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=53459&t=53412 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast [7:71577]
Hi everyone, I was wondering if someone can explain to me what is "Link-Local to L3 to L2 mapping" under Cisco R&S Blue print under In the IP Multicast Section. I read Jeff Doyle II on IP Multicasting and other materials on IP Multicast but I can't seem to depict that concept. Could someone point me in the direction ? Thanks for all your help. RBX10- TAKING THE TEST NEXT WEEK !!! :-) Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71577&t=71577 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast Addressing (corrected typo)
I've not read the McGraw Hill's BUMS book yet :-) I'm reading through McGraw Hill's BCMSN book. Chapter 7 deals with IP = Multicast Addressing. I understand that class D addresses are used = (high order bits set to 1110), but a statement used in the book confuses = me: IP Multicast addresses start with 224.0.0.0 and end with 239.255.255.255 I'm not real keen on where the 239 came from... Thanks All !!! Phil=20 _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast - when is it covered
Is multicast ip's covered in the BSCN portion of the CCNP or is it covered later? Thanx Dyland --- Nothing like a de-motivational poster to lighten the spirit . . . http://www.thinkgeek.com/stuff/posters.html _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast: Router and Switch locations
Currently reading about Multicast, which I have not any experience with yet. If you have a small simple LAN with 1 fileserver, 10 workstations and 1 router to the Internet: INTERNET---[router]---[switch]---[fileserver & 10 workstations] In order for that fileserver to send multicast data to participating workstations without changing the topology, I would have to setup the router with IGMP and CGMP, so the workstation could tell the router that it joined a group, and the router could then inform the switch with CGMP about that workstation. The fileserver would now send multicast data and the switch would know which interface(s) to forward it out to. Since the server and every workstation has their own connection to the switch (and hence has their own individual collision domain), would I be right in assuming that it would not improve the situation to add an additional router to act like a filter between the switch and the server? INTERNET---[router]---[switch]---[10 workstations] | [router2] | [fileserver] Also, will we see multicasting work without a router or an rsm but only with a switch in the future (I know that switches don't understand IGMP)? Thanks, Ole Ole Drews Jensen Systems Network Manager CCNA, MCSE, MCP+I RWR Enterprises, Inc. [EMAIL PROTECTED] http://www.oledrews.com/ccnp NEED A JOB ??? http://www.oledrews.com/job _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Follow up on "multicast worm"
Couple of follow ups on one of the latest threats: - Also see http://service1.symantec.com/sarc/sarc.nsf/html/Linux.Ramen.Worm.html I like the part about it patching the holes that it uses... --Steve Bellovin, http://www.research.att.com/~smb -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Marshall Eubanks Sent: Friday, January 19, 2001 6:43 AM To: [EMAIL PROTECTED] Subject:Re: Second day of rolling blackouts starts Two people have asked me off list about the RAMEN worm, which affects Linux Redhat distro's. Here is brief description of the worm, and a link to more, from Lucy Lynch at Internet2 / UOregon. The multicast implications : This worm scans a portion of the multicast address space. These scans (packets) are viewed as new multicast sources by a PIM multicast enabled router, which encapsulates them and sends them to its RP. The RP creates MSDP Session Announcements FOR EACH SCAN and floods them to every RP neighbor it has in "nearby" AS's, and those repeat the process. The result is a MSDP packet storm. We have gotten 15,000 SA's a minute. Dealing with these can melt down routers. (We had to reboot a Cisco 7204, for example, which apparently either filled up or fragmented its memory beyond usability.) I think it is fair to say that the question of rate limiting and other DOS filtering in PIM/SSM/MSDP multicast is getting serious attention now. Marshall Eubanks "Lucy E. Lynch" wrote: > > a bit more info on ramen here: > > http://members.home.net/dtmartin24/ramen_worm.txt > > "And now, the contents of that ramen.tgz file: All the binaries are in the > archive twice, with RedHat 6.2 and RedHat 7.0 versions. Numerous binaries > were not stripped, which makes the job of taking them apart easier." > > asp: An xinetd config. file that will start up the fake webserver >Used on RedHat 7.0 victim machines. > asp62: HTTP/0.9-compatible server that always serves out the file >/tmp/ramen.tgz to any request - NOT stripped > asp7: RedHat 7-compiled version - NOT stripped > bd62.sh: Does the setup (installing wormserver, removing vulnerable >programs, adding ftp users) for RedHat 6.2 > bd7.sh:Same for RedHat 7.0 > getip.sh: Utility script to get the main external IP address > hackl.sh: Driver to read the .l file and pass addresses to lh.sh > hackw.sh: Driver to read the .w file and pass addresses to wh.sh > index.html: HTML document text > l62: LPRng format string exploit program - NOT stripped > l7:Same but compiled for RedHat 7 - stripped > lh.sh: Driver script to execute the LPRng exploit with several >different options > randb62: Picks a random class-B subnet to scan on - NOT stripped > randb7:Same but compiled for RedHat 7 - NOT stripped > s62: statdx exploit - NOT stripped > s7:Same but compiled for RedHat 7 - stripped > scan.sh: get a classB network from randb and run synscan > start.sh: Replace any index.html with the one from the worm; run getip; >determine if we're RedHat 6.2 or 7.0 and run the appropriate >bd*.sh and start*.sh > start62.sh: start (backgrounded) scan.sh, hackl.sh, and hackw.sh > start7.sh: Same as start62.sh > synscan62: Modified synscan tool - records to .w and .l files - stripped > synscan7: Same but compiled for RedHat 7 - stripped > w62:venglin wu-ftpd exploit - stripped > w7: Same but compiled for RedHat 7 - stripped > wh.sh: Driver script to call the "s" and "w" binaries against a given >target > wu62: Apparently only included by mistake. "strings" shows it to be >very similar to w62; nowhere is this binary ever invoked. > > Lucy E. Lynch Academic User Services > Computing CenterUniversity of Oregon _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Stop multicast to router
Maybe I need a diagram, but you say there is some sort of routing in the equation... can you filter this ??? - Original Message - From: "Tony van Ree" <[EMAIL PROTECTED]> To: "studygroup" <[EMAIL PROTECTED]> Sent: Wednesday, April 04, 2001 11:44 PM Subject: Stop multicast to router > Hi all, > > I have been presented a problem I'm not sure of the answer. > > I have a CAT5000 switch connecting several VLAN's and a Cisco2948 providing routing/switching. One of the VLAN's has a process that uses a multicasts. These multicasts cause the Cisco2948 a little grief. I do not want the Cisco2980 to see the multicast traffic. > > Any clues would be appreciated. > > > Teunis > Hobart, Tasmania > Australia > > > > -- > www.tasmail.com _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Stop multicast to router
you can use CGMP to create a PIM domain and filter the traffic that wayyou will have to still use your 2948 but it will be a little easierGROUP?? steve >From: "Tony van Ree" <[EMAIL PROTECTED]> >Reply-To: "Tony van Ree" <[EMAIL PROTECTED]> >To: "studygroup" <[EMAIL PROTECTED]> >Subject: Stop multicast to router >Date: Thu, 5 Apr 2001 10:44:23 +1000 > > Hi all, > >I have been presented a problem I'm not sure of the answer. > >I have a CAT5000 switch connecting several VLAN's and a Cisco2948 providing >routing/switching. One of the VLAN's has a process that uses a multicasts. > These multicasts cause the Cisco2948 a little grief. I do not want the >Cisco2980 to see the multicast traffic. > >Any clues would be appreciated. > > >Teunis >Hobart, Tasmania >Australia > > > >-- >www.tasmail.com _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
How to Generate Multicast Traffic
I have a Cisco 2500 and a Catalyst6000 using ISL. I want to test Multicast and see how is works, moving through the router. Anyone know how I can generate Multicast traffic on a windows computer and send to the other computer on a different network. What kind of application would I use? Rico _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast Configuration [7:7114]
Hi Friends I have 2 checkpoint Firewalls configured for high availability and load balancing mode. I need to configure the IP Multicast on both the Internal and external interfaces of both firewall. I have configured the common virtual IP on both the external and internal I/Fs. I am using 2900 XL series switch with 12.0(5)XU for connecting both the internal and external I/Fs of the firewall. I need to configure all these 4 interface for multicast grouping. So if there is traffic flow across the FW then the traffic should be forwarded to both the I/Fs. What I need to do to configure IP multicast on the Switch. I think CGMP is by default enabled. Please give me some guidance. regards imran _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=7114&t=7114 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
PIM multicast question [7:7943]
I have the following question, but I don't understand on the answer: When is a dense mode PIM interface added to the mulitcast routing table for a specific group? A)The interface connects a Catalyst switch. Both the router interface and the Catalyst are running CGMP B)The interface is added to the mroute table if DVMRP is heard C)A host has used ICMP to join the group and the router is a designated router D)There are PIM neighbors but the group has been pruned. The answer is B & C. But I thought dense-mode PIM interface is always added to the multicast routing table. Please help. Regards, Hunt Lee IP Solution Analyst Cable and Wireless Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=7943&t=7943 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Ethernet multicast [7:10272]
At 09:12 AM 6/28/01, Ramesh c wrote: >1) Does a Network Interface card support 2^47 ethernet multicast address. The first three bytes are still a vendor code (with the multicast bit turned on). So that reduces the number of possible multicast addresses. >If >so how are the Addresses generated or stored? The Ethernet driver keeps track of which multicasts to listen to. >2)How are the Ip Multicast address mapped to Ethernet multicast address? IP multicasting transmits IP data to a group of hosts that are identified by a single Class-D IP address. In dotted-decimal notation, host group addresses range from 224.0.0.0 to 239.255.255.255. Network stations recognize an address as being a Class-D address because the first four bits must be 1110 in binary. A multicast group is also identified by a MAC-layer multicast address. The Internet Assigned Numbers Authority (IANA) owns a block of MAC-layer addresses that are used for group multicast addresses. The range of addresses for Ethernet is 01:00:5E:00:00:00 -- 01:00:5E:7F:FF:FF. When a station sends a frame to an IP group that is identified by a Class-D address, the station inserts the low-order 23 bits of the Class-D address into the low-order 23 bits of the MAC-layer destination address. The top 9 bits of the Class-D address are not used. The top 25 bits of the MAC address are 01:00:5E followed by a zero, or, in binary: 0001 0100 0 Cheers, Priscilla >Cheers > > >Get 250 color business cards for FREE! >http://businesscards.lycos.com/vp/fastpath/ Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=10292&t=10272 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast setup time [7:16353]
Hello, can anyone write me how much is, approximately, the setup time for a large-scale multicast transmission with a single-sender using PIM-SM/MSDP/MBGP protocols? Thanks Antonio Di Napoli Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=16353&t=16353 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
about multicast address! [7:29057]
dear friends, i got a question on multicast address.by having one ethernet address grouping to multiple multicast addresses.i would like to know how many layer 3 addresses can be mapped by one multicast ethernet address ? and how ?.( i seen in cisco press book , it says 32 layer 3 addresses can be mapped by one ethernet address). any answers? bye ramnath. [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=29057&t=29057 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Multicast adrressing: ip to Mac
I am studying for the switching exam and I am converting ip multicast address to ethernet addresses. What i don't get is that they state in the Cisco press book (page 294/295) "the least 23 least significant bits of the ip multicast group are place into the frame..." "half of the ethernet block 01:00:5e:00:00:00 to 01:00:5e:7f:ff:ff correspond to ip multicast" I really only use twenty when I am converting from binary to hex. Scenario: 224.138.8.5 (to use their example) 1110 1000 1010 1000 0101 01:00:5e:0A:08:05 Since the 01:00:5e:0 are always going to be, then I am only concerned with the least significant 20. Is this right? I did their exercise on page 319/320 and got 100% (their is an errata for on of the address but it is a decimal to binary error) but I did not use the 01:00:5e:0 as the base but 01:00:5e: Thanks! ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
telnet, ping, multicast and etc
Dear friends, Can I ask you some basic question, don't laugh at me :P if u just want to answer me one of the question, just help me . 1) What is difference between ping and telnet? telnet is using port 23, how about PING? which port is that? I understand we can use the access-list to control whether a telnet session can be established, how about ping, Are we using the ip route command to whether PING traffic to pass thru? 2) We open a port in Firewall to let user can telnet to a server in remote site. Does it mean that we can ping to the server. If not, What should we do in order to let user can ping to the server? 3) What is mean by Multicast? I know there is a range of IP for Multicast? But when we need it? Thanks Sim Chee Tong == De informatie opgenomen in dit bericht kan vertrouwelijk zijn en is uitsluitend bestemd voor de geadresseerde. Indien u dit bericht onterecht ontvangt wordt u verzocht de inhoud niet te gebruiken en de afzender direct te informeren door het bericht te retourneren. == The information contained in this message may be confidential and is intended to be exclusively for the addressee. Should you receive this message unintentionally, please do not use the contents herein and notify the sender immediately by return e-mail. == ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
IP Multicast - PIM Designated Routers...
The literature I have (BCMSN notes) refers to the PIM Designated Router in a broadcast environment as having the highest numerical IP address of the neighbouring routers in the same broadcast environment (same ethernet segment). Does anyone know if you can over-ride the IP address on an interface by setting a loopback address (as in OSPF DR elections)? This would have the effect of forcing a specific router to become the PIM DR if it didn't have the highest LAN IP address. Thx. Keith :-) ___ UPDATED Posting Guidelines: http://www.groupstudy.com/list/guide.html FAQ, list archives, and subscription info: http://www.groupstudy.com Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
