Figure 48: Generalized Pseudowire-Id Fec Element - Alcatel-Lucent 7210 SAS M Service Manual

BGP Auto-Discovery for LDP VPLS
The generalized pseudowire-ID FEC element has been designed for auto discovery applications. It
provides a field, the address group identifier (AGI), that is used to signal the membership
information from the VPLS-ID. Separate address fields are provided for the source and target
address associated with the VPLS endpoints called the Source Attachment Individual Identifier
(SAII) and respectively, Target Attachment Individual Identifier (TAII). These fields carry the VSI
ID values for the two instances that are to be connected through the signaled pseudowire.
The detailed format for FEC 129 is depicted in
Each of the FEC fields are designed as a sub-TLV equipped with its own type and length providing
support for new applications. To accommodate the BGP AD information model the following FEC
formats are used:
•
•
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Figure 48: Generalized Pseudowire-ID FEC Element

AGI (type 1) is identical in format and content with the BGP extended community
attribute used to carry the VPLS-ID value.
Source AII (type 1) is a 4 bytes value destined to carry the local VSI-id (outgoing NLRI
minus the RD).
Figure 48.
7210 SAS M Services Guide