Re: Difference between Rendezvous Point ,Designated Router
The rendezvous point is an element in a multicasting environment - can't recall which protocol off the top of my head, it's probably either PIM-DM or -SM. The designated router is an element of OSPF on a broadcast network (ethernet, token ring, etc.). The other routers on the network form their adjacencies with the DR, and the DR makes sure that every router on the broadcast network have the same LSDB. BJ - Original Message - From: rtc To: Cisco ; CISCO GROUPSTUDY Cc: Cisco ; CISCO GROUPSTUDY Sent: Saturday, March 03, 2001 4:48 PM Subject: Difference between Rendezvous Point ,Designated Router what is the Difference between Rendezvous Point and Designated Router? _ 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: Difference between Rendezvous Point ,Designated Router
Er...duh, the DR in a multicast environment. Sorry, brain lock there. The DR is again an element on a broadcast network. The DR acts as the "manager" for that broadcast network if and when it is the upstream network from another router. The downstream router sends its join/leave requests to the DR, regardless of the multicast group it is joining or leaving. This streamlines things from the downstream router's perspective, since it only needs to interact with one other router across this broadcast network. But the DR may not be the direct path to the source of the multicast stream, so the DR might have to forward the request to the correct upstream router across the same network. I'm getting my info from Maufer's "Deploying IP Multicast in the Enterprise" - which isn't Cisco-specific. Maybe someone else could post quotes from the Cisco Press books or CCO about the difference. BJ - Original Message - From: Bradley J. Wilson To: cisco Sent: Saturday, March 03, 2001 5:07 PM Subject: Re: Difference between Rendezvous Point ,Designated Router The rendezvous point is an element in a multicasting environment - can't recall which protocol off the top of my head, it's probably either PIM-DM or -SM. The designated router is an element of OSPF on a broadcast network (ethernet, token ring, etc.). The other routers on the network form their adjacencies with the DR, and the DR makes sure that every router on the broadcast network have the same LSDB. BJ - Original Message - From: rtc To: Cisco ; CISCO GROUPSTUDY Cc: Cisco ; CISCO GROUPSTUDY Sent: Saturday, March 03, 2001 4:48 PM Subject: Difference between Rendezvous Point ,Designated Router what is the Difference between Rendezvous Point and Designated Router? _ 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: Difference between Rendezvous Point ,Designated Router
RTC, I'm studying for my BCMSN right now (test Monday). Coming from an ISP background (high end routers), I'm not used to this "Campus Network" type stuff. I'm reading Karen Webb's Cisco Press book. She mentions DRs in the Multicast section. She states that DRs are elected on Multi-access Segments for both PIM-SM and PIM-DM configurations. She doesn't explain it real deeply (not like you see explanations for the DR/BDR setup of OSPF). But she does say that the routers that are PIM enabled elect the router with the Highest IP address as the DR for the network. In this scenario the DR is responsible for sending out the IGMP query messages. And similar to OSPF, you don't need a DR on point-to-point links. The Rendezvous Point is needed when you configure a router with PIM sparse-mode. Unlike the DR that's used regardless of PIM-SM or PIM-DM. I'm starting to get the feeling that the Rendezvous Point is more important when the hosts that are part of the multicast group are widely spread out through the network. I'd really like to hear from someone experienced with Multicast, my exposure to it is all book-based. This will be the weakest part of my CCNP. Chris -Original Message- From: rtc [mailto:[EMAIL PROTECTED]] Sent: Saturday, March 03, 2001 4:48 PM To: Cisco; CISCO GROUPSTUDY Cc: Cisco; CISCO GROUPSTUDY Subject: Difference between Rendezvous Point ,Designated Router what is the Difference between Rendezvous Point and Designated Router? _ 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: Difference between Rendezvous Point ,Designated Router
Assuming you are talking about PIM-SM , then where you have two routers (PIM-SM) connected to a shared network with a receiver, a single DR should be chosen for the purpose of sending "joins" to the RP in order to build the share tree for that group. If both routers sent joins to the RP for the group you would have duplicate paths and the host/reciever would receive duplicate multicast traffic. PIM-SM is centered on a single, unidirectional shared tree. The root of the tree is the RP. In a shared tree, sources must send the multicast traffic to the root (RP) for the traffic to reach all receivers. Here is two sites for your reading pleasure. Also the Cisco Press book by Beu Willamson is pretty good. http://www.cisco.com/warp/public/732/Tech/multicast/index.html ftp://ftp-eng.cisco.com/ipmulticast.html "Bradley J. Wilson" wrote: > Er...duh, the DR in a multicast environment. Sorry, brain lock there. > > The DR is again an element on a broadcast network. The DR acts as the > "manager" for that broadcast network if and when it is the upstream network > from another router. The downstream router sends its join/leave requests to > the DR, regardless of the multicast group it is joining or leaving. This > streamlines things from the downstream router's perspective, since it only > needs to interact with one other router across this broadcast network. But > the DR may not be the direct path to the source of the multicast stream, so > the DR might have to forward the request to the correct upstream router > across the same network. > > I'm getting my info from Maufer's "Deploying IP Multicast in the > Enterprise" - which isn't Cisco-specific. Maybe someone else could post > quotes from the Cisco Press books or CCO about the difference. > > BJ > > ----- Original Message ----- > From: Bradley J. Wilson > To: cisco > Sent: Saturday, March 03, 2001 5:07 PM > Subject: Re: Difference between Rendezvous Point ,Designated Router > > The rendezvous point is an element in a multicasting environment - can't > recall which protocol off the top of my head, it's probably either PIM-DM > or -SM. > > The designated router is an element of OSPF on a broadcast network > (ethernet, token ring, etc.). The other routers on the network form their > adjacencies with the DR, and the DR makes sure that every router on the > broadcast network have the same LSDB. > > BJ > > - Original Message - > From: rtc > To: Cisco ; CISCO GROUPSTUDY > Cc: Cisco ; CISCO GROUPSTUDY > Sent: Saturday, March 03, 2001 4:48 PM > Subject: Difference between Rendezvous Point ,Designated Router > > what is the Difference between Rendezvous Point and Designated Router? > > _ > 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] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
