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LDP or TDP?

NAVIN PARWAL
Level 2
Level 2

Folks,

I have a MPLS network setup in my lab. I have MPLS Layer3 VPN configured and running. Now, I am reading about Layer-2 VNPS ( EoMPLS) and one of the requirements is to use LDP instead the default TDP for label distribution. My question is if Layer-3 and Layer-2 VPNs can coexist together, what should i use?????

Thanks

2 Replies 2

jhalldn
Level 1
Level 1

Short answer: Yes, L2 and L3 VPN can coexist. Use LDP for label negotiating.

LDP is a standard protocol between MPLS-enabled routers to negotiate the labels (addresses) used to forward packets.

The Cisco proprietary version of this protocol is the TDP.

The virtual circuit setup uses the same LDP signaling mechanism defined for point-to-point services.

Using a directed LDP session, each provider edge advertises a virtual circuit label mapping that is

used as part of the label stack imposed on the Ethernet frames by the ingress provider edge during packet forwarding.

More:

http://www.cisco.com/en/US/customer/tech/tk436/tk891/technologies_q_and_a_item09186a00801ed3bf.shtml

Hope it will get you started...

You can continue to run TDP in the core. While configuring Layer 2 VPNs the L2-PE should support both LDP and TDP. While you configure Layer 2 VCs there will be a directed LDP session initiated from the L2-PE.