MPLS label

[olly ahmed]

As far as I know that there are two label in MPLS (top+bottom). My question is that who (PEs or P) imposes  Top labels and who Bottom label ?

[Vinit Jain]

Any router can allocate or impose a label depending on their role in the network. Talking in the context of MPLS VPN, bottom label is imposed by remote PE (mostly in cases of MPLS VPN where PE allocates VPN Label) and the top label is generally received by P router (IGP or TE label) unless another PE is also acting as a P label

Hope this helps.

Regards

Vinit

[Amit Goyal]

PE router impose both (Top + Bottom) labels if we are talking about MPLS L3 VPN. P routers just do top label swapping depending upon the MPLS forwarding table.

HTH

-Amit