Routing

Hi Cloud,

I interpret you mean P2MP *LSP* instead of LDP. :)

Often with RSVP-TE, you will find point-to-point LSPs established for most applications, except for those that require traffic being sent over LSPs from a single [or more] Ingress LSR to multiple Egress LSRs. For instance, imagine a bunch of IPTV multicast SOURCEs connected to a router, these requiring BW, protection, as well as establishing multiple LSPs towards multiple Egress LSRs requiring the multicast traffic.

For these cases, instead of creating multiple independent LSPs from the Ingress LSR, you would simply create a single P2MP LSPs pointing to multiple exit routers (Egress LSRs) using RSVP-TE P2MP LSP capability.

Under the RSVP-TE PATH message, it describes the LSP type accordingly, and the Ingress-Transit-Egress routers describe it accordingly. For further checks, please refer to this PCAP where once you expand the RSVP PATH message, you will observe what I am trying to describe: https://www.cloudshark.org/captures/9e56ec4da7a2.

Regards,

Elvin