The MPLS WG Archive

[Nagabhushana <Nagabhushana.Ramaswamy@wipro.com>]

Hello,
	I have two queries regarding the implementation of MPLS over a Frame relay
switch.

1. In the MPLS architecture draft it is said that

" 3.26.1. Non-merging LSRs

     The MPLS forwarding procedures is very similar to the forwarding
     procedures used by such technologies as ATM and Frame Relay. That is,
     a unit of data arrives, a label (VPI/VCI or DLCI) is looked up in a
     "cross-connect table", on the basis of that lookup an output port is
     chosen, and the label value is rewritten. In fact, it is possible to
     use such technologies for MPLS forwarding; a label distribution
     protocol can be used as the "signalling protocol" for setting up the
     cross-connect tables. "

what I understand from this is we can use the LDP itself for SVC signalling in a
frame relay network. So in this case the Q.933 signalling is obsolete here. 
So my question now is do we have to reserve any particular DLCI for LDP messages
itself? Is there any standard already defined for this?

secondly, assuming LDP as the signalling protocol, we have to run our LDP stack
over each of the UNI and NNI elements. So this would mean that we have to
support TCP/IP stack(to maintain the integrity of the LDP sessions) and also IP
encapsulatio/decapsulation at each of the NNI elements which is not necessary in
normal FR networks.


thanks in advance
Nagabhushana