PIM-SM

Electing an RP (in brief)

14 October, 2009 Posted by Zarar As CCIE, CCIE SP, Multicast, PIM-DM, PIM-SM (4) Comment

The PIMv2 RFC states:
“This specification does not mandate the use of a single mechanism to provide routers with the information to perform the group-to-RP mapping. Currently four mechanisms are possible, and all four have associated problems:

Static Configuration: A PIM router MUST support the static configuration of group-to-RP mappings. Such a mechanism is not [...]

Categories : CCIE, CCIE SP, Multicast, PIM-DM, PIM-SM

PIM Assert Messages

14 October, 2009 Posted by Zarar As CCIE, CCIE SP, Multicast, PIM-SM (0) Comment

Where multiple PIM routers peer over a shared LAN, it is possible for more than one upstream router to have valid forwarding state for a packet, which can lead to packet duplication. PIM does not attempt to prevent this from occurring. Instead, it detects when this has happened and elects a single forwarder [...]

Categories : CCIE, CCIE SP, Multicast, PIM-SM

Building the shared and shortest path Tree

13 October, 2009 Posted by Zarar As CCIE, CCIE SP, Multicast, PIM-SM (0) Comment

The Shared tree is rooted at the RP and the shortest path tree is rooted at the Source of the multicast traffic.
The following processes will be discussed.

Building the shared tree between the receivers and the RP
Forwarding unicast PIM Register packets from the source to the RP
Building the shortest Path tree between the RP and the [...]

Categories : CCIE, CCIE SP, Multicast, PIM-SM

Pim Packet Formats

12 October, 2009 Posted by Zarar As CCIE, CCIE SP, Multicast, PIM-SM (2) Comment

The following information was taken from the RFCs below.

RFC 4601(Obsoletes RFC 2362) — Protocol Independent Multicast – Sparse Mode (PIM-SM)
RFC 5059 — Bootstrap Router (BSR) Mechanism for Protocol Independent Multicast (PIM)

To read the RFCs please visit the links below.
ftp://ftp.rfc-editor.org/in-notes/rfc4601.txt
ftp://ftp.rfc-editor.org/in-notes/rfc5059.txt
The following PIM packets formats are described within rfc 4601 and 5059.
RFC 4601 PIM Packet Formats

Hello Message [...]

Categories : CCIE, CCIE SP, Multicast, PIM-SM

IPv4 BGP multicast

15 December, 2008 Posted by zismail As BGP, CCIE SP, MSDP, Multicast, PIM-SM (2) Comment

IPv4 BGP multicast announcements can be somewhat confusing. It took a while to get my head around it, so now that I have, I will try to explain.
I have set up the topology below.

Everything has been configured in the above scenario EXCEPT the IPv4 BGP multicast session between RP and ASBR-RP. I want to show [...]

Categories : BGP, CCIE SP, MSDP, Multicast, PIM-SM

Multicast – PIM Sparse Mode

4 December, 2008 Posted by zismail As CCIE SP, Multicast, PIM-SM (0) Comment

Consider the topology below.

Once your IGP and infrastrucutre links are all configured use the following to enable multicast sparse mode.
Step 1 – Enable multicast globally on all routers
multicast-routing
Step 2 – Enable multicast on all interfaces
interface Serial1/0.1 point-to-point
ip pim sparse-mode
Step 3 – Configure an RP on a devices
ip pim rp-address 2.2.2.2
When you enable pim sparse mode [...]

Categories : CCIE SP, Multicast, PIM-SM