RE: L3 Between VLANS- no RSM or MSFC [7:44462]
The answer is router on a stick, make a trunk from the router to the switch and setup the vlans on the router as subinterfaces. Rah -Original Message- From: Phil Lorenz [mailto:[EMAIL PROTECTED]] Sent: 19 May 2002 00:45 To: [EMAIL PROTECTED] Subject: L3 Between VLANS- no RSM or MSFC [7:44462] I'm looking to mock up RSM/ MSFC type routing between VLANs. If my memory serves me correctly, can't I do this with a 4500 (or better) router outfitted with an FE module ??? Can anyone elaborate and/ or offer a few clues to get me researching in the right area ??? Thanks !!! Phil Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44475&t=44462 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Suggesstions(Cisco to Checkpoint) [7:44476]
Hi All, I recently came across this problem and wanna take opinion from you guys. I want to terminate a VPN, originating from a Cisco 7200 box and terminating at Checkpoint VPN-1 gateway. I am also looking for routing failover as I have two routers (running HSRP inside and outside) and two tunnels terminating at the same checkpoint box but as GRE tunnels are not supported by Checkpoint plus tunnel is not terminating on a router, so OSPF failover is not even a option, so I was considering static route failover but I need a IKE keeplive (dead sure supported by Cisco) to be supported by Checkpoint VPN-1. I have no clue whether it is supported or not and whetehr cisco and Checkpoint are interoperable. Plz advice me in this regard. Shahid = Shahid Muhammad Shafi "Every man dies; not every man really lives" remember, if God bringz u 2 it, He WILL bring u thru it!!!- Please help feed hungry people worldwide http://www.hungersite.com/ A small thing each of us can do to help others less fortunate than ourselves __ Do You Yahoo!? LAUNCH - Your Yahoo! Music Experience http://launch.yahoo.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44476&t=44476 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Network Design... Hmmm [7:44417]
""Steve Watson"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > This was not a comparison of network design methodologies, it was mean > to be humorous (I totally agree with the top down process). The idea of > "build a network and they will come" simply does not work! CL: au contraire, mon ami! I give you the small brokerage firm I used to work for. Filled with unsophisticated users. When I arrived there was no WAN and no LAN to speak of - the so called LAN was dictated by the quote service vendor. I put in a real LAN with e-mail. That took off like crazy. I put in a real WAN with the branches able to send e-mail to eachother, and that took off even crazier. I put in an internet connection, and sure there was the usual crap with people checking out the adult entertainment, but you know, I had guys who could prior to my arrival couldn't tun their computers on going out and finding some realy nice investment sites and services that helped them tremendously in their business. At the time of my leaving, the LAN./WAM was starting to show signs of stress. In the course of my cetification pursuit, I have learned all the things I did wrong. But I gotta say, you have to start someplace, and it remains true that if the facilities exist, the user community will find a lot of ways to use those facilities. > > The context of the other book was that no network will function properly > if Layer 1 is not designed correctly. > > BTW, how many is too many? :-) > > Steve > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of > Priscilla Oppenheimer > Sent: Saturday, May 18, 2002 2:04 PM > To: [EMAIL PROTECTED] > Subject: Re: Network Design... Hmmm [7:44417] > > At 08:49 PM 5/17/02, Steve Watson wrote: > >I am reading Priscilla's book "Top Down Network Design" for the second > >time for a refresher and decided to hit the pool after I got home. > > Thanks for reading Top-Down Network Design. I hope you had a nice swim > and > didn't drink too many beers at the pool. ;-) > > >On > >the way out I looked on my book shelf and saw "Advanced IP Network > >Design" that I haven't had a chance to look at yet. So I took it to the > >pool with me. When lo and behold, what did I read on page 5, "The best > >place to start when designing a network is at the bottom". > > Out of context, this is completely meaningless. What else does it say? > > > > > > >Food for thought :-) > > > > > > > >Steve > > > Priscilla Oppenheimer > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44477&t=44417 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: STP and 7 hops [7:44408]
in your travels have you ever run into the gigastack, and its relation to STP? the question came up a short time ago. The Cisco gigastack documentation does not cover STP - only how gigastack works. essentially, using daisy chained gigastack connections, one can connect up to 9 switches. If I understand correctly, the Cisco electronics and switch OS consider this stack a single entity for management purposes - i.e. can be managed from a single IP address. However, Cisco does not say one way or another if the electronics and the switch OS treat this stack as a single device for STP purposes. I'm guessing, based on this and other discussions that it would have to be a single device for STP purposes. It just would be nice if Cisco would provide the specific information. That brings up the corollary question - if you have on two switches gigastacked, then how does STP come into play. In a configuration such as this, again if I understand the documentation correctly, the electronics and the switch OS behave differently. ""Leigh Anne Chisholm"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Actually, the 5-4-3 rule has everything to do with detecting collisions. > It's > a limiting factor of distance so that a collision will be detected within the > first 64 bytes of a frame's transmission (also known as Ethernet's minimum > frame size). It's preferable to detect a collision before the frame leaves > the buffer of the transmitting interface - so that retransmission can be > accomplished at the data link layer rather than left to upper layers. > > Several months ago, Priscilla and I debated the 7 switch rule. If you wanted > to search the archives for the entire thread, it was titled "What's the > diameter of your switched network? [7:17489]" and was discussed at the end of > August, 2001. Here's an excerpt from one of my posts regarding the 7 hop > limit: > > From other statements I've read (Cisco published material) and from the > original excerpt I published, I'd imagine that the placement of the root does > matter. > > "Part of this restriction is coming from the age field BPDU carry: > when a BPDU is propagated from the root bridge towards the leaves of the > tree, the age field is incremented each time it goes though a bridge. > Eventually, when the age field of a BPDU goes beyond max age, it is > discarded. Typically, this will occur if the root is too far away from some > bridges of the network. This issue will impact convergence of the spanning > tree." > > I'd think that if a bridge were to be the third bridge away from the root, > and > another switch was the third bridge on the far side of the root, I wouldn't > expect to see any problems with MaxAge because I can't see the root being too > far from some of the bridges in the network. Now if a bridge were to be the > seventh, I could see how that would impose a greater delay and possibly > negatively impact the MaxAge parameter. Now my question would be... does > this > really apply in today's networks or is this more of a limitation of > yesteryear's "software-based bridges"? > > And essentially, that's the conclusion Priscilla and I came to - that the 7 > hop radius doesn't really seem to apply to today's switched environments... > You might want to check with her again though - Priscilla just authored a new > book on troubleshooting campus networks and may updated her thinking. > > > -- Leigh Anne Chisholm (CCNP, CCDP) -Original Message- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > > Steven A. Ridder > > Sent: Saturday, May 18, 2002 5:16 AM > > To: [EMAIL PROTECTED] > > Subject: Re: STP and 7 hops [7:44408] > > > > > > I believe the 5-4-3 rule is for repeaters, not switches. > > > > > > ""Brian Hill"" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > Steven, > > > > > > The 7 hop limit is from the root bridge, as STP calculates the tree from > > the > > > root. Historically, I am not sure why it's 7, but Ethernet has a base hop > > > "limit" of 4 switches (5-4-3 rule), so it doesn't really matter so much. > > The > > > reason for the 4 hop limit in Ethernet is simple: For 10 Mb or full > duplex > > > 100 Mb connections, the limit is mostly to reduce noise from the > > > amplification of the signal as it passes through the switches/hubs, where > > as > > > in 100Mb half-duplex connections, it is mostly to keep the propogation > > delay > > > within specs. > > > > > > Hope this helps, > > > > > > Brian Hill > > > CCNP, CCDP, MCSE 2000 (Charter Member),MCSE+I (NT4.0), > > > MCSA (Charter Member), MCP+I, MCP(21), Inet+, Net+, A+ > > > Lead Technology Architect, TechTrain > > > Author: Cisco, The Complete Reference > > > http://www.alfageek.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44478&t=44408 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Repor
RE: Network Design... Hmmm [7:44417]
I was speaking in general terms. While it is conceivable to build a network without customer requirements and (to a degree) it will be functional, the network has no room for growth and more than likely will be hard to manage. The buzzwords scalability and efficiency come to mind. The best place to start (correction the ONLY place to start) is to define the customer's requirements (now and for the 18 - 24 months) so you design and implement a viable solution that has room to grow. I have done, in the past, what you have mentioned below and were met with the same frustration you were (inefficiency and network loading problems). That's why I tell my customers; don't tell me you need a T-1 (nowadays everybody wants a DS3) tell me what will ride this circuit and we will do an analysis of bandwidth to determine what is best... yada.. yada.. yada.. Steve -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Chuck Sent: Sunday, May 19, 2002 12:22 PM To: [EMAIL PROTECTED] Subject: Re: Network Design... Hmmm [7:44417] ""Steve Watson"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > This was not a comparison of network design methodologies, it was mean > to be humorous (I totally agree with the top down process). The idea of > "build a network and they will come" simply does not work! CL: au contraire, mon ami! I give you the small brokerage firm I used to work for. Filled with unsophisticated users. When I arrived there was no WAN and no LAN to speak of - the so called LAN was dictated by the quote service vendor. I put in a real LAN with e-mail. That took off like crazy. I put in a real WAN with the branches able to send e-mail to eachother, and that took off even crazier. I put in an internet connection, and sure there was the usual crap with people checking out the adult entertainment, but you know, I had guys who could prior to my arrival couldn't tun their computers on going out and finding some realy nice investment sites and services that helped them tremendously in their business. At the time of my leaving, the LAN./WAM was starting to show signs of stress. In the course of my cetification pursuit, I have learned all the things I did wrong. But I gotta say, you have to start someplace, and it remains true that if the facilities exist, the user community will find a lot of ways to use those facilities. > > The context of the other book was that no network will function properly > if Layer 1 is not designed correctly. > > BTW, how many is too many? :-) > > Steve > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of > Priscilla Oppenheimer > Sent: Saturday, May 18, 2002 2:04 PM > To: [EMAIL PROTECTED] > Subject: Re: Network Design... Hmmm [7:44417] > > At 08:49 PM 5/17/02, Steve Watson wrote: > >I am reading Priscilla's book "Top Down Network Design" for the second > >time for a refresher and decided to hit the pool after I got home. > > Thanks for reading Top-Down Network Design. I hope you had a nice swim > and > didn't drink too many beers at the pool. ;-) > > >On > >the way out I looked on my book shelf and saw "Advanced IP Network > >Design" that I haven't had a chance to look at yet. So I took it to the > >pool with me. When lo and behold, what did I read on page 5, "The best > >place to start when designing a network is at the bottom". > > Out of context, this is completely meaningless. What else does it say? > > > > > > >Food for thought :-) > > > > > > > >Steve > > > Priscilla Oppenheimer > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44479&t=44417 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: OSPF inter-area summarization [7:44465]
When specifying the summary address, you need to use the network address of the summarization The address you specified is within the summary, its just not the network address. Appling the mask against your address : 0010=32 1100=192 - 00xx=0 Remember 1's we care about, 0's we don't. Now for the network, we set the don't care about bits to 0, (and for the broadcast they are all 1's) This leads to: 00->00 = 0 Your summary is 137.20.1.0 255.255.255.192 This gives a range of address's from 137.20.1.0-137.20.1.63 (network-broadcast) Soo. Area 11 range 137.20.1.0 255.255.255.192 would be the most exact match that you could advertise Thanks Larry -Original Message- From: Michael Witte [mailto:[EMAIL PROTECTED]] Sent: Saturday, May 18, 2002 7:27 PM To: [EMAIL PROTECTED] Subject: OSPF inter-area summarization [7:44465] I am trying to do a lab that needs a inter-area ospf summary address configured I have two loopbacks 137.20.1.17/28 and 137.20.1.33/28. These are then of course on networks 137.20.1.16 and 137.20.1.32. Taking the last octet of the subnets into binary we have: 16= 0001 32= 0010 Acording to Doyle and everything else I have read I should be able to summarize by masking the first two bits. I should be able to use: area 11 range 137.20.1.32 255.255.255.192. I am not able to and the router says I have a invalid address/mask. Furthermore the solution to the lab uses "area 11 range 137.20.1.0 255.255.255.0" which creates a summary address to all addresses of 137.20.1.X. What am I missing. This does work and I am able to ping the loopbacks but the math doesn't work for me. I should be able to summarize the 16 and 32 subnets. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44480&t=44465 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Network Design... Hmmm [7:44417]
I'll defend the practice of analyzing humorous statements as a point of origin for inquiries potentially leading to insight until the end of time and beyond. One of the reasons that this is possible is precisely BECAUSE practices such as "build a network and they will come" occur whether or not they work, in turn somewhat contributing to the ecomonic viability of professions shared by some members of the group. - Original Message - From: "Steve Watson" To: Sent: Saturday, May 18, 2002 3:28 PM Subject: RE: Network Design... Hmmm [7:44417] > This was not a comparison of network design methodologies, it was mean > to be humorous (I totally agree with the top down process). The idea of > "build a network and they will come" simply does not work! > > The context of the other book was that no network will function properly > if Layer 1 is not designed correctly. > > BTW, how many is too many? :-) > > Steve > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of > Priscilla Oppenheimer > Sent: Saturday, May 18, 2002 2:04 PM > To: [EMAIL PROTECTED] > Subject: Re: Network Design... Hmmm [7:44417] > > At 08:49 PM 5/17/02, Steve Watson wrote: > >I am reading Priscilla's book "Top Down Network Design" for the second > >time for a refresher and decided to hit the pool after I got home. > > Thanks for reading Top-Down Network Design. I hope you had a nice swim > and > didn't drink too many beers at the pool. ;-) > > >On > >the way out I looked on my book shelf and saw "Advanced IP Network > >Design" that I haven't had a chance to look at yet. So I took it to the > >pool with me. When lo and behold, what did I read on page 5, "The best > >place to start when designing a network is at the bottom". > > Out of context, this is completely meaningless. What else does it say? > > > > > > >Food for thought :-) > > > > > > > >Steve > > > Priscilla Oppenheimer > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44481&t=44417 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Network Design... Hmmm [7:44417]
> Hey Chuck- don't forget your friendly TCP conversations. They too will find ways of using facilities (burst) you thought you had :o) Phil -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Chuck Sent: Sunday, May 19, 2002 12:22 PM To: [EMAIL PROTECTED] Subject: Re: Network Design... Hmmm [7:44417] ""Steve Watson"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > This was not a comparison of network design methodologies, it was mean > to be humorous (I totally agree with the top down process). The idea of > "build a network and they will come" simply does not work! CL: au contraire, mon ami! I give you the small brokerage firm I used to work for. Filled with unsophisticated users. When I arrived there was no WAN and no LAN to speak of - the so called LAN was dictated by the quote service vendor. I put in a real LAN with e-mail. That took off like crazy. I put in a real WAN with the branches able to send e-mail to eachother, and that took off even crazier. I put in an internet connection, and sure there was the usual crap with people checking out the adult entertainment, but you know, I had guys who could prior to my arrival couldn't tun their computers on going out and finding some realy nice investment sites and services that helped them tremendously in their business. At the time of my leaving, the LAN./WAM was starting to show signs of stress. In the course of my cetification pursuit, I have learned all the things I did wrong. But I gotta say, you have to start someplace, and it remains true that if the facilities exist, the user community will find a lot of ways to use those facilities. > > The context of the other book was that no network will function properly > if Layer 1 is not designed correctly. > > BTW, how many is too many? :-) > > Steve > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of > Priscilla Oppenheimer > Sent: Saturday, May 18, 2002 2:04 PM > To: [EMAIL PROTECTED] > Subject: Re: Network Design... Hmmm [7:44417] > > At 08:49 PM 5/17/02, Steve Watson wrote: > >I am reading Priscilla's book "Top Down Network Design" for the second > >time for a refresher and decided to hit the pool after I got home. > > Thanks for reading Top-Down Network Design. I hope you had a nice swim > and > didn't drink too many beers at the pool. ;-) > > >On > >the way out I looked on my book shelf and saw "Advanced IP Network > >Design" that I haven't had a chance to look at yet. So I took it to the > >pool with me. When lo and behold, what did I read on page 5, "The best > >place to start when designing a network is at the bottom". > > Out of context, this is completely meaningless. What else does it say? > > > > > > >Food for thought :-) > > > > > > > >Steve > > > Priscilla Oppenheimer > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44482&t=44417 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: STP and 7 hops [7:44408]
I asked Cisco, and STP treats the stack as separate switches. ""Chuck"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > in your travels have you ever run into the gigastack, and its relation to > STP? > > the question came up a short time ago. The Cisco gigastack documentation > does not cover STP - only how gigastack works. > > essentially, using daisy chained gigastack connections, one can connect up > to 9 switches. If I understand correctly, the Cisco electronics and switch > OS consider this stack a single entity for management purposes - i.e. can be > managed from a single IP address. However, Cisco does not say one way or > another if the electronics and the switch OS treat this stack as a single > device for STP purposes. > > I'm guessing, based on this and other discussions that it would have to be a > single device for STP purposes. It just would be nice if Cisco would provide > the specific information. > > That brings up the corollary question - if you have on two switches > gigastacked, then how does STP come into play. In a configuration such as > this, again if I understand the documentation correctly, the electronics and > the switch OS behave differently. > > > > > ""Leigh Anne Chisholm"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > Actually, the 5-4-3 rule has everything to do with detecting collisions. > > It's > > a limiting factor of distance so that a collision will be detected within > the > > first 64 bytes of a frame's transmission (also known as Ethernet's minimum > > frame size). It's preferable to detect a collision before the frame > leaves > > the buffer of the transmitting interface - so that retransmission can be > > accomplished at the data link layer rather than left to upper layers. > > > > Several months ago, Priscilla and I debated the 7 switch rule. If you > wanted > > to search the archives for the entire thread, it was titled "What's the > > diameter of your switched network? [7:17489]" and was discussed at the end > of > > August, 2001. Here's an excerpt from one of my posts regarding the 7 hop > > limit: > > > > From other statements I've read (Cisco published material) and from the > > original excerpt I published, I'd imagine that the placement of the root > does > > matter. > > > > "Part of this restriction is coming from the age field BPDU carry: > > when a BPDU is propagated from the root bridge towards the leaves of the > > tree, the age field is incremented each time it goes though a bridge. > > Eventually, when the age field of a BPDU goes beyond max age, it is > > discarded. Typically, this will occur if the root is too far away from > some > > bridges of the network. This issue will impact convergence of the spanning > > tree." > > > > I'd think that if a bridge were to be the third bridge away from the root, > > and > > another switch was the third bridge on the far side of the root, I > wouldn't > > expect to see any problems with MaxAge because I can't see the root being > too > > far from some of the bridges in the network. Now if a bridge were to be > the > > seventh, I could see how that would impose a greater delay and possibly > > negatively impact the MaxAge parameter. Now my question would be... does > > this > > really apply in today's networks or is this more of a limitation of > > yesteryear's "software-based bridges"? > > > > And essentially, that's the conclusion Priscilla and I came to - that the > 7 > > hop radius doesn't really seem to apply to today's switched > environments... > > You might want to check with her again though - Priscilla just authored a > new > > book on troubleshooting campus networks and may updated her thinking. > > > > > > -- Leigh Anne Chisholm (CCNP, CCDP) -Original Message- > > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > > > Steven A. Ridder > > > Sent: Saturday, May 18, 2002 5:16 AM > > > To: [EMAIL PROTECTED] > > > Subject: Re: STP and 7 hops [7:44408] > > > > > > > > > I believe the 5-4-3 rule is for repeaters, not switches. > > > > > > > > > ""Brian Hill"" wrote in message > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > Steven, > > > > > > > > The 7 hop limit is from the root bridge, as STP calculates the tree > from > > > the > > > > root. Historically, I am not sure why it's 7, but Ethernet has a base > hop > > > > "limit" of 4 switches (5-4-3 rule), so it doesn't really matter so > much. > > > The > > > > reason for the 4 hop limit in Ethernet is simple: For 10 Mb or full > > duplex > > > > 100 Mb connections, the limit is mostly to reduce noise from the > > > > amplification of the signal as it passes through the switches/hubs, > where > > > as > > > > in 100Mb half-duplex connections, it is mostly to keep the propogation > > > delay > > > > within specs. > > > > > > > > Hope this helps, > > > > > > > > Brian Hill > > > > CCNP, CCDP, MCSE 2000 (Charter Member),MCSE+I (NT4.0), > > > > MCSA (Charter Member), MCP+
Re: STP and 7 hops [7:44408]
were the people you asked able to address the max STP diameter of 7 issue then? ""Steven A. Ridder"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > I asked Cisco, and STP treats the stack as separate switches. > > > ""Chuck"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > in your travels have you ever run into the gigastack, and its relation to > > STP? > > > > the question came up a short time ago. The Cisco gigastack documentation > > does not cover STP - only how gigastack works. > > > > essentially, using daisy chained gigastack connections, one can connect up > > to 9 switches. If I understand correctly, the Cisco electronics and switch > > OS consider this stack a single entity for management purposes - i.e. can > be > > managed from a single IP address. However, Cisco does not say one way or > > another if the electronics and the switch OS treat this stack as a single > > device for STP purposes. > > > > I'm guessing, based on this and other discussions that it would have to be > a > > single device for STP purposes. It just would be nice if Cisco would > provide > > the specific information. > > > > That brings up the corollary question - if you have on two switches > > gigastacked, then how does STP come into play. In a configuration such as > > this, again if I understand the documentation correctly, the electronics > and > > the switch OS behave differently. > > > > > > > > > > ""Leigh Anne Chisholm"" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > Actually, the 5-4-3 rule has everything to do with detecting collisions. > > > It's > > > a limiting factor of distance so that a collision will be detected > within > > the > > > first 64 bytes of a frame's transmission (also known as Ethernet's > minimum > > > frame size). It's preferable to detect a collision before the frame > > leaves > > > the buffer of the transmitting interface - so that retransmission can be > > > accomplished at the data link layer rather than left to upper layers. > > > > > > Several months ago, Priscilla and I debated the 7 switch rule. If you > > wanted > > > to search the archives for the entire thread, it was titled "What's the > > > diameter of your switched network? [7:17489]" and was discussed at the > end > > of > > > August, 2001. Here's an excerpt from one of my posts regarding the 7 > hop > > > limit: > > > > > > From other statements I've read (Cisco published material) and from the > > > original excerpt I published, I'd imagine that the placement of the root > > does > > > matter. > > > > > > "Part of this restriction is coming from the age field BPDU carry: > > > when a BPDU is propagated from the root bridge towards the leaves of the > > > tree, the age field is incremented each time it goes though a bridge. > > > Eventually, when the age field of a BPDU goes beyond max age, it is > > > discarded. Typically, this will occur if the root is too far away from > > some > > > bridges of the network. This issue will impact convergence of the > spanning > > > tree." > > > > > > I'd think that if a bridge were to be the third bridge away from the > root, > > > and > > > another switch was the third bridge on the far side of the root, I > > wouldn't > > > expect to see any problems with MaxAge because I can't see the root > being > > too > > > far from some of the bridges in the network. Now if a bridge were to be > > the > > > seventh, I could see how that would impose a greater delay and possibly > > > negatively impact the MaxAge parameter. Now my question would be... > does > > > this > > > really apply in today's networks or is this more of a limitation of > > > yesteryear's "software-based bridges"? > > > > > > And essentially, that's the conclusion Priscilla and I came to - that > the > > 7 > > > hop radius doesn't really seem to apply to today's switched > > environments... > > > You might want to check with her again though - Priscilla just authored > a > > new > > > book on troubleshooting campus networks and may updated her thinking. > > > > > > > > > -- Leigh Anne Chisholm (CCNP, CCDP) -Original Message- > > > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > > > > Steven A. Ridder > > > > Sent: Saturday, May 18, 2002 5:16 AM > > > > To: [EMAIL PROTECTED] > > > > Subject: Re: STP and 7 hops [7:44408] > > > > > > > > > > > > I believe the 5-4-3 rule is for repeaters, not switches. > > > > > > > > > > > > ""Brian Hill"" wrote in message > > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > > Steven, > > > > > > > > > > The 7 hop limit is from the root bridge, as STP calculates the tree > > from > > > > the > > > > > root. Historically, I am not sure why it's 7, but Ethernet has a > base > > hop > > > > > "limit" of 4 switches (5-4-3 rule), so it doesn't really matter so > > much. > > > > The > > > > > reason for the 4 hop limit in Ethernet is simple: For 10 Mb or full > > > duplex > > > > > 100 Mb co
RE: STP and 7 hops [7:44408]
At 10:49 PM 5/18/02, Brian Hill wrote: > > Slot time is an issue for all CSMA/CD networks, regardless of > > transmission > > speed. It is certainly discussed as a fundamental issue in all > > versions of > > IEEE 802.3 from the first in January 1985. > >This would be the first time I have heard this statement. I was under the >impression that the slot time's primary purpose was to facilitate collision >detection. In other words, that the slot time represented the length of time >an Ethernet host listened to its own packet to detect a collision. Is this >not true? If it is true, how does the slot time have anything to do with >full duplex Ethernet? Full duplex is used on a point-to-point link where each side has a dedicated transmit circuit. It's not multiple access (MA). Since it's not MA, the sender doesn't need to sense the carrier first (CS). Collision detection (CD) isn't necessary because the two stations sending at the same time is legal. So full duplex wasn't what I had in mind when I said that slot time is an issue for all CSMA/CD networks. I don't know why you are mentioning it here. The IEEE annex that covered full-duplex (802.3x) probably didn't mention slot time. That annex was rolled into the 802.3 2000 edition, however, which of course does cover slot time since it still covers CSMA/CD, repeaters, etc. (in addition to full-duplex operation.) > > >However, thinking about it, based solely on the switching > > mode, it seems > > >that all switches (and even a lot of hubs now) buffer the > > packet in RAM and > > >then forward it, which means, as someone stated, that the > > packet is "rebuilt". > > > > A hub that did that wouldn't really be a hub. The extra delay > > would cause a > > problem, for one thing. > >Priscilla, I can't find the logic in this. If the hub doesn't buffer the >frame, I don't see any way it could possibly rebuild it. A hub doesn't understand frames, doesn't buffer them, and doesn't rebuild them. It rebuilds bits. It regenerates the signal one bit at a time. It syncs up on the signal by looking at the preamble. It regenerates the preamble (to avoid the problem of the preamble shrinking from repeaters taking time to sync up on it) and forwards the rest of the bits. It also extends fragments that are less than 96 bits (including the preamble). If it has any "RAM," it's only a few bits big. We used to teach the gory details of repeater behavior but that's about all I remember at this time. >I mean, from what I >can tell, either the hub amplifies the original signal (which you and >documentation state is untrue), or it has to somehow record the incoming >signal (into RAM?) and then send the regenerated signal back out, doesn't >it? I am not talking about buffering the entire packet, therby increasing >the delay >, my thought process was simply that either it sent the signal on, >amplifying it, or it stored and analyzed the signal, then forwarded it back >out. This is based on my understanding that the signal itself is analog, >even if it is represented digitally. In other words, either you can increase >the analog signal by running it through a circuit, or you have to convert >the original analog signal into a digital representation (+3.12 volts might >be determined to be a binary 1 or simply 3 volts, for instance), and then >create a new analog signal. I am no EE either, however, so perhaps my >thinking is flawed. Is this how "digital" repeating is done? Well, now we are getting into EE talk. ;-) Everything is analog at some level, isn't it? But an Ethernet repeater works on a Manchester encoded digital signal. (MLT-3 encoding for 100 Mbps). I think your second statement is closest to the truth (that the repeater converts the analog signal into a digital representation and creates a new analog signal). But I don't know the exact details. I'm sorry I was so punchy in the previous message. Priscilla Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44485&t=44408 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Network Design... Hmmm [7:44417]
obviously you've never worked in a brokerage firm ;-> my point being that you can get away with a lot, up to a certain point. When that point is reached, you can throw hardware and/or bandwidth at the thing, and buy some more time. Maybe a lot of time. Or you start over, and do things right, from the start. I would suggest that there are special cases even in the most well designed and planned networks, where there are islands of chaos. I agree that there is nothing like having whomever tell you what the solution is, rather than tell you the problem. We need a T1. We need a P5 machine. We need more RAM. Whatever. Working for whom I work for these days, the answer is always "yes, sir. Sign right here" ;-> ""Steve Watson"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > I was speaking in general terms. While it is conceivable to build a > network without customer requirements and (to a degree) it will be > functional, the network has no room for growth and more than likely will > be hard to manage. The buzzwords scalability and efficiency come to > mind. > > The best place to start (correction the ONLY place to start) is to > define the customer's requirements (now and for the 18 - 24 months) so > you design and implement a viable solution that has room to grow. > > I have done, in the past, what you have mentioned below and were met > with the same frustration you were (inefficiency and network loading > problems). That's why I tell my customers; don't tell me you need a T-1 > (nowadays everybody wants a DS3) tell me what will ride this circuit and > we will do an analysis of bandwidth to determine what is best... yada.. > yada.. yada.. > > Steve > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of > Chuck > Sent: Sunday, May 19, 2002 12:22 PM > To: [EMAIL PROTECTED] > Subject: Re: Network Design... Hmmm [7:44417] > > ""Steve Watson"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > This was not a comparison of network design methodologies, it was mean > > to be humorous (I totally agree with the top down process). The idea > of > > "build a network and they will come" simply does not work! > > > CL: au contraire, mon ami! I give you the small brokerage firm I used to > work for. Filled with unsophisticated users. When I arrived there was no > WAN > and no LAN to speak of - the so called LAN was dictated by the quote > service > vendor. > > I put in a real LAN with e-mail. That took off like crazy. > > I put in a real WAN with the branches able to send e-mail to eachother, > and > that took off even crazier. > > I put in an internet connection, and sure there was the usual crap with > people checking out the adult entertainment, but you know, I had guys > who > could prior to my arrival couldn't tun their computers on going out and > finding some realy nice investment sites and services that helped them > tremendously in their business. > > At the time of my leaving, the LAN./WAM was starting to show signs of > stress. In the course of my cetification pursuit, I have learned all the > things I did wrong. But I gotta say, you have to start someplace, and it > remains true that if the facilities exist, the user community will find > a > lot of ways to use those facilities. > > > > > > > > The context of the other book was that no network will function > properly > > if Layer 1 is not designed correctly. > > > > BTW, how many is too many? :-) > > > > Steve > > > > -Original Message- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf > Of > > Priscilla Oppenheimer > > Sent: Saturday, May 18, 2002 2:04 PM > > To: [EMAIL PROTECTED] > > Subject: Re: Network Design... Hmmm [7:44417] > > > > At 08:49 PM 5/17/02, Steve Watson wrote: > > >I am reading Priscilla's book "Top Down Network Design" for the > second > > >time for a refresher and decided to hit the pool after I got home. > > > > Thanks for reading Top-Down Network Design. I hope you had a nice swim > > and > > didn't drink too many beers at the pool. ;-) > > > > >On > > >the way out I looked on my book shelf and saw "Advanced IP Network > > >Design" that I haven't had a chance to look at yet. So I took it to > the > > >pool with me. When lo and behold, what did I read on page 5, "The > best > > >place to start when designing a network is at the bottom". > > > > Out of context, this is completely meaningless. What else does it say? > > > > > > > > > > >Food for thought :-) > > > > > > > > > > > >Steve > > > > > > Priscilla Oppenheimer > > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44486&t=44417 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: OSPF inter-area summarization [7:44465]
Larry, I had the idea right to use 255.255.255.192 mask because that is where the bit boundary is. My question is why can't you use the 137.20.1.32/26 to summarize from 32-95. What if you had a subnet zero and didn't want that summarized. Why do I have to use the 137.20.1.0 network for summarization? If we use this example: 172.20.8.0/22 1000 >8 172.20.12.0/22 1100 >12 ^Bit boundary=248 1000 >248 1000 >8 subnet 1000 >248 mask 1000 >8 subnet I think I see now.If you binary AND the subnet and mask and get the subnet you can use that subnet in your summarization. If the binary AND becomes zero, then you must use zero as your network in the summary command. Is this correct? I spent too much time on this and need things like this put to bed for the Lab in November. Thanks. area 11 range 172.20.8.0 255.255.248.0 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44487&t=44465 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: why my gigabit switch port speed only hit 10M? [7:44333]
Hi there, I always check the giga bandwidth with some software's that can originate streams of data to the end point and the best software is from NETIQ called Qcheck try it , its free I can give u a copy if you won`t find Regards Joupin www.joupin.com ""Sim, CT (Chee Tong)"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Hi.. I had installed a gigabit switch (Cisco 3550). But I feel the speed > of slow. I connected my two PC in GigabitEthernet0/1 and 0/2. I transfer a > huge file between the two PCs ( the transfer last for 4 mins). But the > maximum speed is only 10Mbit ? Why?? What is wrong?? I thought it should > be go up to 1000M or 1Gbits??? > > ! > interface GigabitEthernet0/1 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/2 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/3 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/4 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/5 > no ip address > snmp trap link-status > ! > > cat35-L8-1#sh int gi0/1 > GigabitEthernet0/1 is up, line protocol is up > Hardware is Gigabit Ethernet, address is 0005.313e.7581 (bia > 0005.313e.7581) > MTU 1500 bytes, BW 100 Kbit, DLY 10 usec, > reliability 255/255, txload 1/255, rxload 1/255 > Encapsulation ARPA, loopback not set > Keepalive set (10 sec) > Full-duplex, 1000Mb/s > input flow-control is off, output flow-control is on > ARP type: ARPA, ARP Timeout 04:00:00 > Last input never, output 00:00:00, output hang never > Last clearing of "show interface" counters never > Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 > Queueing strategy: fifo > Output queue :0/40 (size/max) > 5 minute input rate 0 bits/sec, 0 packets/sec > 5 minute output rate 12000 bits/sec, 14 packets/sec > 905784 packets input, 1303109052 bytes, 0 no buffer > Received 66 broadcasts, 0 runts, 0 giants, 0 throttles > 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored > 0 input packets with dribble condition detected > 1042863 packets output, 190194068 bytes, 0 underruns > 0 output errors, 0 collisions, 2 interface resets > 0 babbles, 0 late collision, 0 deferred > 0 lost carrier, 0 no carrier > 0 output buffer failures, 0 output buffers swapped out > GigabitEthernet0/2 is up, line protocol is up > Hardware is Gigabit Ethernet, address is 0005.313e.7582 (bia > 0005.313e.7582) > MTU 1500 bytes, BW 100 Kbit, DLY 10 usec, > reliability 255/255, txload 1/255, rxload 1/255 > Encapsulation ARPA, loopback not set > Keepalive set (10 sec) > Full-duplex, 1000Mb/s > input flow-control is off, output flow-control is on > ARP type: ARPA, ARP Timeout 04:00:00 > Last input never, output 00:00:00, output hang never > Last clearing of "show interface" counters never > Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 > Queueing strategy: fifo > Output queue :0/40 (size/max) > 5 minute input rate 0 bits/sec, 0 packets/sec > 5 minute output rate 12000 bits/sec, 13 packets/sec > 1486 packets input, 179522 bytes, 0 no buffer > Received 1421 broadcasts, 0 runts, 0 giants, 0 throttles > 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored > 0 input packets with dribble condition detected > 1948976 packets output, 1493416902 bytes, 0 underruns > 0 output errors, 0 collisions, 2 interface resets > 0 babbles, 0 late collision, 0 deferred > 0 lost carrier, 0 no carrier > 0 output buffer failures, 0 output buffers swapped out > > > > > > == > 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. > > > == Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44488&t=44333 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: STP and 7 hops [7:44408]
At 03:51 PM 5/19/02, Chuck wrote: >were the people you asked able to address the max STP diameter of 7 issue >then? Maybe they blew off the max STP diameter of 7 issue. ;-) It is just a recommendation. Even IEEE 802.1D just uses that word (recommendation). There's nothing in the protocol that would stop you from having a larger network, is there? The Max Age timer defaults to 20 seconds, so that doesn't limit you to 7 hops. Also, with gigaswitch, do all those 9 switches remain in the spanning tree? I don't know anything about gigaswitch, as you can probably tell, but I would think the 7 limit would only apply to the logical topology, if it applies at all. Priscilla >""Steven A. Ridder"" wrote in message >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > I asked Cisco, and STP treats the stack as separate switches. > > > > > > ""Chuck"" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > in your travels have you ever run into the gigastack, and its relation >to > > > STP? > > > > > > the question came up a short time ago. The Cisco gigastack documentation > > > does not cover STP - only how gigastack works. > > > > > > essentially, using daisy chained gigastack connections, one can connect >up > > > to 9 switches. If I understand correctly, the Cisco electronics and >switch > > > OS consider this stack a single entity for management purposes - i.e. >can > > be > > > managed from a single IP address. However, Cisco does not say one way or > > > another if the electronics and the switch OS treat this stack as a >single > > > device for STP purposes. > > > > > > I'm guessing, based on this and other discussions that it would have to >be > > a > > > single device for STP purposes. It just would be nice if Cisco would > > provide > > > the specific information. > > > > > > That brings up the corollary question - if you have on two switches > > > gigastacked, then how does STP come into play. In a configuration such >as > > > this, again if I understand the documentation correctly, the electronics > > and > > > the switch OS behave differently. > > > > > > > > > > > > > > > ""Leigh Anne Chisholm"" wrote in message > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > Actually, the 5-4-3 rule has everything to do with detecting >collisions. > > > > It's > > > > a limiting factor of distance so that a collision will be detected > > within > > > the > > > > first 64 bytes of a frame's transmission (also known as Ethernet's > > minimum > > > > frame size). It's preferable to detect a collision before the frame > > > leaves > > > > the buffer of the transmitting interface - so that retransmission can >be > > > > accomplished at the data link layer rather than left to upper layers. > > > > > > > > Several months ago, Priscilla and I debated the 7 switch rule. If you > > > wanted > > > > to search the archives for the entire thread, it was titled "What's >the > > > > diameter of your switched network? [7:17489]" and was discussed at the > > end > > > of > > > > August, 2001. Here's an excerpt from one of my posts regarding the 7 > > hop > > > > limit: > > > > > > > > From other statements I've read (Cisco published material) and from >the > > > > original excerpt I published, I'd imagine that the placement of the >root > > > does > > > > matter. > > > > > > > > "Part of this restriction is coming from the age field BPDU carry: > > > > when a BPDU is propagated from the root bridge towards the leaves of >the > > > > tree, the age field is incremented each time it goes though a bridge. > > > > Eventually, when the age field of a BPDU goes beyond max age, it is > > > > discarded. Typically, this will occur if the root is too far away from > > > some > > > > bridges of the network. This issue will impact convergence of the > > spanning > > > > tree." > > > > > > > > I'd think that if a bridge were to be the third bridge away from the > > root, > > > > and > > > > another switch was the third bridge on the far side of the root, I > > > wouldn't > > > > expect to see any problems with MaxAge because I can't see the root > > being > > > too > > > > far from some of the bridges in the network. Now if a bridge were to >be > > > the > > > > seventh, I could see how that would impose a greater delay and >possibly > > > > negatively impact the MaxAge parameter. Now my question would be... > > does > > > > this > > > > really apply in today's networks or is this more of a limitation of > > > > yesteryear's "software-based bridges"? > > > > > > > > And essentially, that's the conclusion Priscilla and I came to - that > > the > > > 7 > > > > hop radius doesn't really seem to apply to today's switched > > > environments... > > > > You might want to check with her again though - Priscilla just >authored > > a > > > new > > > > book on troubleshooting campus networks and may updated her thinking. > > > > > > > > > > > > -- Leigh Anne Chisholm (CCNP, CCDP) -Original Message- > > > >
Re: why my gigabit switch port speed only hit 10M? [7:44333]
interesting. I had a similar conversation with a customer last week. the customer said they were running 100 megabit on cat 3 wire. I asked them how they knew. The answer was essentially that they had link. ( connectivity ) there are many reasons you may not be getting real ( or perceived ) gigabit on the link. Others have pointed those reasons out - slow disk drives, busy server, or whatever. just cuz you have connectivity doesn't automatically mean you will get the fastest throughput possible. ""Sim, CT (Chee Tong)"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Hi.. I had installed a gigabit switch (Cisco 3550). But I feel the speed > of slow. I connected my two PC in GigabitEthernet0/1 and 0/2. I transfer a > huge file between the two PCs ( the transfer last for 4 mins). But the > maximum speed is only 10Mbit ? Why?? What is wrong?? I thought it should > be go up to 1000M or 1Gbits??? > > ! > interface GigabitEthernet0/1 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/2 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/3 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/4 > no ip address > snmp trap link-status > ! > interface GigabitEthernet0/5 > no ip address > snmp trap link-status > ! > > cat35-L8-1#sh int gi0/1 > GigabitEthernet0/1 is up, line protocol is up > Hardware is Gigabit Ethernet, address is 0005.313e.7581 (bia > 0005.313e.7581) > MTU 1500 bytes, BW 100 Kbit, DLY 10 usec, > reliability 255/255, txload 1/255, rxload 1/255 > Encapsulation ARPA, loopback not set > Keepalive set (10 sec) > Full-duplex, 1000Mb/s > input flow-control is off, output flow-control is on > ARP type: ARPA, ARP Timeout 04:00:00 > Last input never, output 00:00:00, output hang never > Last clearing of "show interface" counters never > Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 > Queueing strategy: fifo > Output queue :0/40 (size/max) > 5 minute input rate 0 bits/sec, 0 packets/sec > 5 minute output rate 12000 bits/sec, 14 packets/sec > 905784 packets input, 1303109052 bytes, 0 no buffer > Received 66 broadcasts, 0 runts, 0 giants, 0 throttles > 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored > 0 input packets with dribble condition detected > 1042863 packets output, 190194068 bytes, 0 underruns > 0 output errors, 0 collisions, 2 interface resets > 0 babbles, 0 late collision, 0 deferred > 0 lost carrier, 0 no carrier > 0 output buffer failures, 0 output buffers swapped out > GigabitEthernet0/2 is up, line protocol is up > Hardware is Gigabit Ethernet, address is 0005.313e.7582 (bia > 0005.313e.7582) > MTU 1500 bytes, BW 100 Kbit, DLY 10 usec, > reliability 255/255, txload 1/255, rxload 1/255 > Encapsulation ARPA, loopback not set > Keepalive set (10 sec) > Full-duplex, 1000Mb/s > input flow-control is off, output flow-control is on > ARP type: ARPA, ARP Timeout 04:00:00 > Last input never, output 00:00:00, output hang never > Last clearing of "show interface" counters never > Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 > Queueing strategy: fifo > Output queue :0/40 (size/max) > 5 minute input rate 0 bits/sec, 0 packets/sec > 5 minute output rate 12000 bits/sec, 13 packets/sec > 1486 packets input, 179522 bytes, 0 no buffer > Received 1421 broadcasts, 0 runts, 0 giants, 0 throttles > 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored > 0 input packets with dribble condition detected > 1948976 packets output, 1493416902 bytes, 0 underruns > 0 output errors, 0 collisions, 2 interface resets > 0 babbles, 0 late collision, 0 deferred > 0 lost carrier, 0 no carrier > 0 output buffer failures, 0 output buffers swapped out > > > > > > == > 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. > > > == Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44490&t=44333 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Some real theory [7:44491]
If anyone is interested, Radia Perlman's PhD dissertation on Byzantine robustness of routing protocols is finally on line. Do not do as I did and download the PostScript, which was almost 40 meg. PDF is BOUND to be smaller. http://www.lcs.mit.edu/publications/pubs/pdf/MIT-LCS-TR-429.pdf Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44491&t=44491 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: STP and 7 hops [7:44408]
STP is really not an issue in the kind of application where gigastack makes sense. For example, take an office of 400 users plus servers and printers, occupying a contiguous space. Basic file and print sharing plus an internet connection. Rather than buy a honking 65xx, you throw in a few 3550-48's and gigastack them. The electronics work in conjunction with the switch OS to create a half duplex bus between the switches. ( The interesting thing is that electronics are apparently smart enough to determine if there are only two devices stacked, in which case the bus is full duplex. ) That's the question about gigastack - whether the entire stack is treated as one switch, the way it is for management purposes, or if standard STP applies. We had a thread on this a few weeks ago, but none of us could find an answer in the Cisco documentation. that's why I asked Steven ( who asked Cisco ) what Cisco had to say about spanning tree over a gigastack setup. I'm willing to bet that in a gigastack situation, that STP is disabled ( where it would be enabled if you stacked the switches using the 10/100 ports, or using regular gbics and daisy chaining the gig ports. ) But I can't find documentation that clarifies. This does give me some food for thought. I'm working with a very large university on a switch design. I am pretty sure that they have several instances where their diameter is greater than seven ( building to building to building to core ). However, being the sophisticates they are, I am certain they are running spanning tree per vlan, and in that case the tree would go back only to the core, and so would have a diameter no greater than 4 in any place I can see from their setup. this seems to be another one of the great discussions that make this group valuable. ""Priscilla Oppenheimer"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > At 03:51 PM 5/19/02, Chuck wrote: > >were the people you asked able to address the max STP diameter of 7 issue > >then? > > Maybe they blew off the max STP diameter of 7 issue. ;-) It is just a > recommendation. Even IEEE 802.1D just uses that word (recommendation). > There's nothing in the protocol that would stop you from having a larger > network, is there? The Max Age timer defaults to 20 seconds, so that > doesn't limit you to 7 hops. > > Also, with gigaswitch, do all those 9 switches remain in the spanning tree? > I don't know anything about gigaswitch, as you can probably tell, but I > would think the 7 limit would only apply to the logical topology, if it > applies at all. > > Priscilla > > > > >""Steven A. Ridder"" wrote in message > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > I asked Cisco, and STP treats the stack as separate switches. > > > > > > > > > ""Chuck"" wrote in message > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > in your travels have you ever run into the gigastack, and its relation > >to > > > > STP? > > > > > > > > the question came up a short time ago. The Cisco gigastack > documentation > > > > does not cover STP - only how gigastack works. > > > > > > > > essentially, using daisy chained gigastack connections, one can connect > >up > > > > to 9 switches. If I understand correctly, the Cisco electronics and > >switch > > > > OS consider this stack a single entity for management purposes - i.e. > >can > > > be > > > > managed from a single IP address. However, Cisco does not say one way > or > > > > another if the electronics and the switch OS treat this stack as a > >single > > > > device for STP purposes. > > > > > > > > I'm guessing, based on this and other discussions that it would have to > >be > > > a > > > > single device for STP purposes. It just would be nice if Cisco would > > > provide > > > > the specific information. > > > > > > > > That brings up the corollary question - if you have on two switches > > > > gigastacked, then how does STP come into play. In a configuration such > >as > > > > this, again if I understand the documentation correctly, the > electronics > > > and > > > > the switch OS behave differently. > > > > > > > > > > > > > > > > > > > > ""Leigh Anne Chisholm"" wrote in message > > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > > Actually, the 5-4-3 rule has everything to do with detecting > >collisions. > > > > > It's > > > > > a limiting factor of distance so that a collision will be detected > > > within > > > > the > > > > > first 64 bytes of a frame's transmission (also known as Ethernet's > > > minimum > > > > > frame size). It's preferable to detect a collision before the frame > > > > leaves > > > > > the buffer of the transmitting interface - so that retransmission can > >be > > > > > accomplished at the data link layer rather than left to upper layers. > > > > > > > > > > Several months ago, Priscilla and I debated the 7 switch rule. If > you > > > > wanted > > > > > to search the archives for the entire thread, it was titled "What's > >the > > > > > diame
RE: OSPF inter-area summarization [7:44465]
If I follow what you are saying, then yes, whatever the AND'ing process of the subnet mask and the address space is what your summarization is. Just AND your subnet mask and network statement together. That will give you your summarization range. Case in point, 137.20.1.32 255.255.255.192 Using on the last octet 00 10 = 32 11 00 = 192 00 00 = 0 which is your summarization. Now lets get tricky and summarization 137 and 158 for the 4th octet 10001001 = 137 1000 = 158 1110 = 1 equals common bits, 0's unique.. = 224 Soo 10001001 = 137 1110 = 224 100x = 128 So to summarize these 2 address's as close as possible you would use 137.20.1.128 255.255.255.224 (/27) Notice that I didn't use 137.20.1.137/27 or 137.20.1.158 /27 as if you tried you would get the error you previously mentioned. You would need to use: Area ?? Range 137.20.1.128 255.255.255.224 I hope this makes sense. I'm horrible at explaining things. You should learn sub/super-netting backwards and forwards. Not just for the test, but for real live work experience. On a side note, if you are in the habit of using a subnet calc, I would get out of that habit. I think that they are one of the worst things ever invented. It doesn't aide in the understanding of how IP addressing works, and In fact I think that it allows people to get by without the detailed Knowledge they need. JMHO though :) Thanks Larry -Original Message- From: Michael Witte [mailto:[EMAIL PROTECTED]] Sent: Sunday, May 19, 2002 3:08 PM To: [EMAIL PROTECTED] Subject: Re: OSPF inter-area summarization [7:44465] Larry, I had the idea right to use 255.255.255.192 mask because that is where the bit boundary is. My question is why can't you use the 137.20.1.32/26 to summarize from 32-95. What if you had a subnet zero and didn't want that summarized. Why do I have to use the 137.20.1.0 network for summarization? If we use this example: 172.20.8.0/22 1000 >8 172.20.12.0/22 1100 >12 ^Bit boundary=248 1000 >248 1000 >8 subnet 1000 >248 mask 1000 >8 subnet I think I see now.If you binary AND the subnet and mask and get the subnet you can use that subnet in your summarization. If the binary AND becomes zero, then you must use zero as your network in the summary command. Is this correct? I spent too much time on this and need things like this put to bed for the Lab in November. Thanks. area 11 range 172.20.8.0 255.255.248.0 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44493&t=44465 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: STP and 7 hops [7:44408]
I didn't ask about the max number of switches, just that if the stack=1 hop or number of switches in stack=hop. As for what Pricilla stated, I guess the 7 hop is a recommendation, not a set-in-stone rule. Which is good, since I just proposed a network that has an 8 hop diameter. ""Chuck"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > were the people you asked able to address the max STP diameter of 7 issue > then? > > > ""Steven A. Ridder"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > I asked Cisco, and STP treats the stack as separate switches. > > > > > > ""Chuck"" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > in your travels have you ever run into the gigastack, and its relation > to > > > STP? > > > > > > the question came up a short time ago. The Cisco gigastack documentation > > > does not cover STP - only how gigastack works. > > > > > > essentially, using daisy chained gigastack connections, one can connect > up > > > to 9 switches. If I understand correctly, the Cisco electronics and > switch > > > OS consider this stack a single entity for management purposes - i.e. > can > > be > > > managed from a single IP address. However, Cisco does not say one way or > > > another if the electronics and the switch OS treat this stack as a > single > > > device for STP purposes. > > > > > > I'm guessing, based on this and other discussions that it would have to > be > > a > > > single device for STP purposes. It just would be nice if Cisco would > > provide > > > the specific information. > > > > > > That brings up the corollary question - if you have on two switches > > > gigastacked, then how does STP come into play. In a configuration such > as > > > this, again if I understand the documentation correctly, the electronics > > and > > > the switch OS behave differently. > > > > > > > > > > > > > > > ""Leigh Anne Chisholm"" wrote in message > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > Actually, the 5-4-3 rule has everything to do with detecting > collisions. > > > > It's > > > > a limiting factor of distance so that a collision will be detected > > within > > > the > > > > first 64 bytes of a frame's transmission (also known as Ethernet's > > minimum > > > > frame size). It's preferable to detect a collision before the frame > > > leaves > > > > the buffer of the transmitting interface - so that retransmission can > be > > > > accomplished at the data link layer rather than left to upper layers. > > > > > > > > Several months ago, Priscilla and I debated the 7 switch rule. If you > > > wanted > > > > to search the archives for the entire thread, it was titled "What's > the > > > > diameter of your switched network? [7:17489]" and was discussed at the > > end > > > of > > > > August, 2001. Here's an excerpt from one of my posts regarding the 7 > > hop > > > > limit: > > > > > > > > From other statements I've read (Cisco published material) and from > the > > > > original excerpt I published, I'd imagine that the placement of the > root > > > does > > > > matter. > > > > > > > > "Part of this restriction is coming from the age field BPDU carry: > > > > when a BPDU is propagated from the root bridge towards the leaves of > the > > > > tree, the age field is incremented each time it goes though a bridge. > > > > Eventually, when the age field of a BPDU goes beyond max age, it is > > > > discarded. Typically, this will occur if the root is too far away from > > > some > > > > bridges of the network. This issue will impact convergence of the > > spanning > > > > tree." > > > > > > > > I'd think that if a bridge were to be the third bridge away from the > > root, > > > > and > > > > another switch was the third bridge on the far side of the root, I > > > wouldn't > > > > expect to see any problems with MaxAge because I can't see the root > > being > > > too > > > > far from some of the bridges in the network. Now if a bridge were to > be > > > the > > > > seventh, I could see how that would impose a greater delay and > possibly > > > > negatively impact the MaxAge parameter. Now my question would be... > > does > > > > this > > > > really apply in today's networks or is this more of a limitation of > > > > yesteryear's "software-based bridges"? > > > > > > > > And essentially, that's the conclusion Priscilla and I came to - that > > the > > > 7 > > > > hop radius doesn't really seem to apply to today's switched > > > environments... > > > > You might want to check with her again though - Priscilla just > authored > > a > > > new > > > > book on troubleshooting campus networks and may updated her thinking. > > > > > > > > > > > > -- Leigh Anne Chisholm (CCNP, CCDP) -Original Message- > > > > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf > Of > > > > > Steven A. Ridder > > > > > Sent: Saturday, May 18, 2002 5:16 AM > > > > > To: [EMAIL PROTECTED] > > > > > Subject: Re: STP and 7 hops [7:44408] >
Way Off Topic - Strategic and tactical thinking - any Civil War [7:44495]
Way way off topic. I am having a discussion with someone about strategic versus tactical thinking. the context is where in that dichotomy CIO's / CTO's should be. Someone used the analogy of various military generals. In any case, my contention is that Grant was neither. He merely threw resources ( soldiers ) at the problem, and eventually won because he had more resources to throw. Lee was at best a tactical thinker who in the end lost in part because he could not accept that his lieutenant James Longstreet was a superior strategic thinker and so ignored his good advice. Contact me off line. It's bad enough that I even post the question here. thanks. apologies to everyone else. Chuck Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44495&t=44495 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Some real theory [7:44491]
the link you provide is only a 10 meg document. ;-> ""Howard C. Berkowitz"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > If anyone is interested, Radia Perlman's PhD dissertation on > Byzantine robustness of routing protocols is finally on line. Do not > do as I did and download the PostScript, which was almost 40 meg. PDF > is BOUND to be smaller. > > http://www.lcs.mit.edu/publications/pubs/pdf/MIT-LCS-TR-429.pdf Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44494&t=44491 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Some real theory [7:44491]
I find Ms. Perlman's summary of the OSI model quite interesting. Love the way she completely disengages from the whole session layer, presentation layer, application layer arguement. Anyone know - does Ms Perlman tap dance? Because she does a great job of it in this section!!! :-> ""Howard C. Berkowitz"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > If anyone is interested, Radia Perlman's PhD dissertation on > Byzantine robustness of routing protocols is finally on line. Do not > do as I did and download the PostScript, which was almost 40 meg. PDF > is BOUND to be smaller. > > http://www.lcs.mit.edu/publications/pubs/pdf/MIT-LCS-TR-429.pdf Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44497&t=44491 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
ATM question [7:44498]
I think this a silly question, but I'm not able to find a clear answer at cisco.com I have been wondering if i have a OC-3 line and multiples PVCs configured, how is bandwidth allocated?, I mean, if I have 10 PVCs is bandwitdh 15.5 Mbps per PVC or is shared dynamically among all PVCs, so if only one PVC is transmitting it can take all bandwidth for it? This is the sho int for two pvcs, as you can see BW is 155Mbps in both of them ATM8/0/0.100 is up, line protocol is up Hardware is cyBus ENHANCED ATM PA Internet address is 69.20.2.1/30 MTU 4470 bytes, BW 149760 Kbit, DLY 80 usec, ATM8/0/0.101 is up, line protocol is up Hardware is cyBus ENHANCED ATM PA Internet address is 172.18.252.253/30 MTU 4470 bytes, BW 149760 Kbit, DLY 80 usec, I think that in frame relay bandwidth is not shared between PVCs but I'm not sure.. Thanks in advance. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44498&t=44498 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: STP and 7 hops [7:44408]
you know, it suddenly occurs to me that I have been barking up the wrong [spanning] tree, so to speak. Let me guess - there is no maximum STP diameter in actuality because there is mechanism for enforcing a max diameter. The BPDU's apparently contain a field which shows distance from the root, and this value is incremented each time it crosses a bridge. If that field is the root path cost field, then this is a four byte value and that means a spanning tree could theoretically have a max distance from the root of 64000 or so? It's just that the recommendation in terms of "best practice" is diameter of 7. thanks to Marty A. for providing the link that was the spike that finally began to sink through this thick head. ""Chuck"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > STP is really not an issue in the kind of application where gigastack makes > sense. For example, take an office of 400 users plus servers and printers, > occupying a contiguous space. Basic file and print sharing plus an internet > connection. Rather than buy a honking 65xx, you throw in a few 3550-48's and > gigastack them. The electronics work in conjunction with the switch OS to > create a half duplex bus between the switches. ( The interesting thing is > that electronics are apparently smart enough to determine if there are only > two devices stacked, in which case the bus is full duplex. ) > > That's the question about gigastack - whether the entire stack is treated as > one switch, the way it is for management purposes, or if standard STP > applies. We had a thread on this a few weeks ago, but none of us could find > an answer in the Cisco documentation. that's why I asked Steven ( who asked > Cisco ) what Cisco had to say about spanning tree over a gigastack setup. > I'm willing to bet that in a gigastack situation, that STP is disabled ( > where it would be enabled if you stacked the switches using the 10/100 > ports, or using regular gbics and daisy chaining the gig ports. ) But I > can't find documentation that clarifies. > > This does give me some food for thought. I'm working with a very large > university on a switch design. I am pretty sure that they have several > instances where their diameter is greater than seven ( building to building > to building to core ). However, being the sophisticates they are, I am > certain they are running spanning tree per vlan, and in that case the tree > would go back only to the core, and so would have a diameter no greater than > 4 in any place I can see from their setup. > > this seems to be another one of the great discussions that make this group > valuable. > > > > ""Priscilla Oppenheimer"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > At 03:51 PM 5/19/02, Chuck wrote: > > >were the people you asked able to address the max STP diameter of 7 issue > > >then? > > > > Maybe they blew off the max STP diameter of 7 issue. ;-) It is just a > > recommendation. Even IEEE 802.1D just uses that word (recommendation). > > There's nothing in the protocol that would stop you from having a larger > > network, is there? The Max Age timer defaults to 20 seconds, so that > > doesn't limit you to 7 hops. > > > > Also, with gigaswitch, do all those 9 switches remain in the spanning > tree? > > I don't know anything about gigaswitch, as you can probably tell, but I > > would think the 7 limit would only apply to the logical topology, if it > > applies at all. > > > > Priscilla > > > > > > > > >""Steven A. Ridder"" wrote in message > > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > I asked Cisco, and STP treats the stack as separate switches. > > > > > > > > > > > > ""Chuck"" wrote in message > > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > > in your travels have you ever run into the gigastack, and its > relation > > >to > > > > > STP? > > > > > > > > > > the question came up a short time ago. The Cisco gigastack > > documentation > > > > > does not cover STP - only how gigastack works. > > > > > > > > > > essentially, using daisy chained gigastack connections, one can > connect > > >up > > > > > to 9 switches. If I understand correctly, the Cisco electronics and > > >switch > > > > > OS consider this stack a single entity for management purposes - > i.e. > > >can > > > > be > > > > > managed from a single IP address. However, Cisco does not say one > way > > or > > > > > another if the electronics and the switch OS treat this stack as a > > >single > > > > > device for STP purposes. > > > > > > > > > > I'm guessing, based on this and other discussions that it would have > to > > >be > > > > a > > > > > single device for STP purposes. It just would be nice if Cisco would > > > > provide > > > > > the specific information. > > > > > > > > > > That brings up the corollary question - if you have on two switches > > > > > gigastacked, then how does STP come into play. In a configuration > such > > >as > > > > > this, again if I understand t
Re: Some real theory [7:44491]
I gather the document was scanned in, using its typewritten source. I'm getting a bit seasick, between my astigmatism and the tilt of the page relative to horizontal. :-> good paper, BTW. Even if totally irrelevant to the pursuit of certification, salary, and other ends. ""Howard C. Berkowitz"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > If anyone is interested, Radia Perlman's PhD dissertation on > Byzantine robustness of routing protocols is finally on line. Do not > do as I did and download the PostScript, which was almost 40 meg. PDF > is BOUND to be smaller. > > http://www.lcs.mit.edu/publications/pubs/pdf/MIT-LCS-TR-429.pdf Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44500&t=44491 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: OSPF inter-area summarization [7:44465]
Great explaination. I just had issues with not being able to use my .32 network address but now I see why.I am taking the road to CCIE very carefully and try to understand exactly why things are the way they are. That is why I love working on the networking end of things; There is a definitive reason for every action. there are also standards(RFC's) that need to be followed. I do a lot of Microsoft stuff at work and you apply a patch that overwrites some .dll and a part of your website doesn't work. Its so frustrating. I worked for 20 years in the electronics field and you could calculate exactly what changing a value would do. this stuff is very simular. Thanks for the help only about 1000 more things to conquer. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44501&t=44465 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Network Design... Hmmm [7:44417]
I don't think Priscilla has to get into too many arguments with Retana, Slice and White (the Advanced IP Network Design authors). While it does claim that the best place to start is at the bottom: the physical layer, it then promptly ignores discussion of the physical layer (this is and IP network design book, after all, not a physical network design book) and states that "A well-designed topology is the basis for all stable networks" (and that bit's in bold). It gets into more specifics than TDND, and I reckon this book is a good complement. TDND for the general design principles that can be applied to any technologies, and AIND (hmm, doesn't have the same ring) for specific ideas on implementing OSPF, providing redundancy, etc etc. Any book that gives me specific quotable ammunition to use against the more peculiar theories of Dilbertian PHBs is a good book, in my opinion. But seriously, taking Cisco books to the pool?? Gawd, no wonder IT people have a reputation for social weirdness ;-) JMcL (no offence intended - and the thought of a pool is a bit chilling here as they're forecasting possible snow). - Forwarded by Jenny Mcleod/NSO/CSDA on 20/05/2002 09:34 am - "Leigh Anne Chisholm" Sent by: [EMAIL PROTECTED] 18/05/2002 01:21 pm Please respond to "Leigh Anne Chisholm" To: [EMAIL PROTECTED] cc: Subject:RE: Network Design... Hmmm [7:44417] Is this part of a business decision process?: And what's really interesting, is that in the Cisco Internet Design book, it says to start at the Core layer and work downwards... Personally, I'm going with Priscilla! (It's a girl thing...) -- Leigh Anne > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > Steve Watson > Sent: Friday, May 17, 2002 6:50 PM > To: [EMAIL PROTECTED] > Subject: Network Design... Hmmm [7:44417] > > > I am reading Priscilla's book "Top Down Network Design" for the second > time for a refresher and decided to hit the pool after I got home. On > the way out I looked on my book shelf and saw "Advanced IP Network > Design" that I haven't had a chance to look at yet. So I took it to the > pool with me. When lo and behold, what did I read on page 5, "The best > place to start when designing a network is at the bottom". > > > > Food for thought :-) > > > > Steve Important: This e-mail is intended for the use of the addressee and may contain information that is confidential, commercially valuable or subject to legal or parliamentary privilege. If you are not the intended recipient you are notified that any review, re-transmission, disclosure, use or dissemination of this communication is strictly prohibited by several Commonwealth Acts of Parliament. If you have received this communication in error please notify the sender immediately and delete all copies of this transmission together with any attachments. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44502&t=44417 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Some real theory [7:44491]
>the link you provide is only a 10 meg document. ;-> Bless .pdf. I downloaded .ps without looking. > > >""Howard C. Berkowitz"" wrote in message >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... >> If anyone is interested, Radia Perlman's PhD dissertation on >> Byzantine robustness of routing protocols is finally on line. Do not >> do as I did and download the PostScript, which was almost 40 meg. PDF >> is BOUND to be smaller. >> > > http://www.lcs.mit.edu/publications/pubs/pdf/MIT-LCS-TR-429.pdf If there's interest, I can probably dig up some other formative dissertations, such as the original concepts of IP multicast routing (Steve Deering) and quite a bit on BGP stability. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44504&t=44491 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: BYL WIRUS W POCZCIE DO CIEBIE OD egeria@kki.krakow.pl [7:44506]
First time I've seen forward Polish notation on the list. >V I R U S A L E R T > >Our viruschecker found the >System antyvirusowy w Krakowski Komercyjny Internet znalazl VIRUS !! >o nazwie: > > I-Worm.Klez.h > I-Worm.Klez.h > >virus(es) in an email to you from: >w poczcie do Ciebie od: > >[EMAIL PROTECTED] > >Delivery of the email was stopped! >Dostarczanie listu zostalo wstrzymane! > > >The ID of your quarantined message is: >numer identyfikacyjny chorego listu jest: > >virus-20020520-005314-22756 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44506&t=44506 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Some real theory [7:44491]
>I find Ms. Perlman's summary of the OSI model quite interesting. Love the >way she completely disengages from the whole session layer, presentation >layer, application layer arguement. Anyone know - does Ms Perlman tap dance? >Because she does a great job of it in this section!!! :-> I can't say whether she tap dances -- I suspect not -- but she is an absolutely delightful lecturer, as long as you accept having routing theory presented in perfect Yenta. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44505&t=44491 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
I got it now! [7:44507]
Ok new summary this time with eigrp. Summarize 170.10.10.1/24,161.10.10.1/24,160.10.10.1/24 170=10101010 161=1011 160=1010 ^Bit Boundary Mask=1110 (224) 160=1010 224=1110 AND=1010(160) We can use 160 for Network # Int E0 ip summary-address eigrp 1 160.0.0.0 224.0.0.0 sh ip route O E1 160.0.0.0/3 [110/212] via 137.20.103.1 Weird huh? Pings are successful so I have this down! Thanks Guys! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44507&t=44507 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Mounting Brackets? [7:44503]
I recently purchased a 2501 on ebay, I recieved it and it does not have the mounting brackets for a rack, does anyone know where to get them? Thanks, Justin Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44503&t=44503 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: STP and 7 hops [7:44408]
Priscilla Oppenheimer wrote: > > The IEEE annex that covered full-duplex (802.3x) probably > didn't mention > slot time. That annex was rolled into the 802.3 2000 edition, > however, > which of course does cover slot time since it still covers > CSMA/CD, > repeaters, etc. (in addition to full-duplex operation.) > Thanks, I was beginning to think I had bad info on slot time as well. It turns out you were saying that all devices that use CSMA/CD (i.e. multiaccess), not all Ethernet devices, use the slot time, which is how I understood it in the first place, I just misunderstood what you were saying :( > Well, now we are getting into EE talk. ;-) Everything is analog > at some > level, isn't it? But an Ethernet repeater works on a Manchester > encoded > digital signal. (MLT-3 encoding for 100 Mbps). I think your > second > statement is closest to the truth (that the repeater converts > the analog > signal into a digital representation and creates a new analog > signal). But > I don't know the exact details. Great, that makes perfect sense :) There is that Manchester encoding again. Do you know where I can find good documentation on it? > > I'm sorry I was so punchy in the previous message. > No problem Priscilla :) You guys (and gals) actually cleared up a lot of old misconceptions in this whole long list of stuff, which is great considering that documents on the dirty inner workings of Ethernet are hard to find unless you happen to be an IEEE member. :P Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44508&t=44408 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Mounting Brackets? [7:44503]
I recently purchased a 2501 on ebay, I recieved it and it does not have the mounting brackets for a rack, does anyone know where to get them? Thanks, Justin Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44503&t=44503 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: I got it now! [7:44507]
You can actually extend the summary to a .240 since those are all the same. The summary-address stays the same, just the mask changes in this situation. Thanks Larry -Original Message- From: Michael Witte [mailto:[EMAIL PROTECTED]] Sent: Sunday, May 19, 2002 7:37 PM To: [EMAIL PROTECTED] Subject: I got it now! [7:44507] Ok new summary this time with eigrp. Summarize 170.10.10.1/24,161.10.10.1/24,160.10.10.1/24 170=10101010 161=1011 160=1010 ^Bit Boundary Mask=1110 (224) 160=1010 224=1110 AND=1010(160) We can use 160 for Network # Int E0 ip summary-address eigrp 1 160.0.0.0 224.0.0.0 sh ip route O E1 160.0.0.0/3 [110/212] via 137.20.103.1 Weird huh? Pings are successful so I have this down! Thanks Guys! Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44509&t=44507 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Some real theory [7:44491]
How about putting them up on the ftp site? Much Appreciated... Nigel - Original Message - From: "Howard C. Berkowitz" To: Sent: Sunday, May 19, 2002 8:29 PM Subject: Re: Some real theory [7:44491] > >the link you provide is only a 10 meg document. ;-> > > Bless .pdf. I downloaded .ps without looking. > > > > > > >""Howard C. Berkowitz"" wrote in message > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > >> If anyone is interested, Radia Perlman's PhD dissertation on > >> Byzantine robustness of routing protocols is finally on line. Do not > >> do as I did and download the PostScript, which was almost 40 meg. PDF > >> is BOUND to be smaller. > >> > > > http://www.lcs.mit.edu/publications/pubs/pdf/MIT-LCS-TR-429.pdf > > If there's interest, I can probably dig up some other formative > dissertations, such as the original concepts of IP multicast routing > (Steve Deering) and quite a bit on BGP stability. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44510&t=44491 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]