Many service providers offer "BGP/MPLS IP VPN" service to their
customers. Existing IETF standards specify the procedures and
protocols that a service provider uses in order to offer this service
to customers who have IP unicast and IP multicast traffic in their
VPNs. It is also desirable to be able to support customers who have
MPLS multicast traffic in their VPNs. This document specifies the
procedures and protocol extensions that are needed to support
customers who use the Multicast Extensions to Label Distribution
Protocol (mLDP) as the control protocol for their MPLS multicast
traffic. Existing standards do provide some support for customers
who use mLDP, but only under a restrictive set of circumstances.
This document generalizes the existing support to include all cases
where the customer uses mLDP, without any restrictions.