Subject: Query on draft draft-ietf-l2vpn-vpls-bgp-08

From: "Abhay D.S" <[email-masked]>
Date: Tue, 14 Nov 2006 10:11:55 +0800

hi Group,

In this draft-ietf-l2vpn-vpls-bgp-08 draft,

3.2.  Signaling

    Once discovery is done, each pair of PEs in a VPLS must be able to
    establish (and tear down) pseudowires to each other, i.e., exchange
    (and withdraw) demultiplexors.  This process is known as signaling.
    Signaling is also used to transmit certain characteristics of the
    pseudowires that a PE sets up for a given VPLS.

    Recall that a demultiplexor is used to distinguish among several
    different streams of traffic carried over a tunnel, each stream
    possibly representing a different service.  In the case of VPLS, the
    demultiplexor not only says to which specific VPLS a packet belongs,
    but also identifies the ingress PE. 

    "*The former information is used
    for forwarding the packet; the latter information is used for
    learning MAC addresses.*"   The demultiplexor described here is an MPLS
    label.  However, note that the PE-to-PE tunnels need not be MPLS
    tunnels.

    The information in quotes latter information is used for learning 
MAC address , Im not very clear about this , why to lean the macaddress ?

    Thank you,
    Abhay