Technical Summary
Sometimes an IP multicast tree, constructed by Protocol Independent
Multicast (PIM), needs to pass through an MPLS domain in which
Multipoint LDP (mLDP) Point-to-Multipoint and/or Multipoint-to-
Multipoint Labels Switched Paths (LSPs) can be created. The part of
the IP multicast tree that traverses the MPLS domain can be
instantiated as a multipoint LSP. When a PIM Join message is
received at the border of the MPLS domain, information from that
message is encoded into mLDP messages. When the mLDP messages reach
the border of the next IP domain, the encoded information is used to
generate PIM messages that can be sent through the IP domain. The
result is an IP multicast tree consisting of a set of IP multicast
sub-trees that are spliced together with a multipoint LSP. This
document describes procedures how IP multicast trees are spliced
together with multipoint LSPs.
Working Group Summary
The MPLS working group has a few non-MPLS-TP documents that fell
into the cracks when we were allocating almost all of our time to
wrapping up the MPLS-TP documents. This document is one of them.
Version -04 of the document was working group last called in
October 2011, it was updated based on on comments during working
group last call. After that the shepherd fumbled and left the
draft without attention for almost 6 months.
When we finally got around to paying attention to the document
again the document shepherd re-reviewed it and found there was no
reason to re-issue a working group last call. The draft is stable.
This document has a strong support in the working group
and has been well reviewed. We had good discussions both
on the mailing list and at the f2f meetings.
Document Quality
We know of existing implementations and intentions to implement
this specification.
AD review resulted in a new revision clarifying a number of small
points.
Personnel
Loa Andersson (loa@pi.nu) is the document shepherd.
Adrian Farrel (adrian@olddog.co.uk) is the responsible AD.