On a carrier's MPLS VPN network, PE1 and PE2 transmit data packets between VPNs. After PE1 receives VPN route 172.16.1.0/24 from a client, it converts the route into a VPNv4 route and distributes label 1027 to the packet. After the packet arrives at PE2, PE2 distributes label 1025 to the packet. When a client on PE2 accesses this route, what are the outer and inner labels in the packet transmitted over the carrier network?

Question

Quizplus · Accepted Answer

The outer label is the one used by the MPLS network to route the packet to the correct PE router, which is 1025 in this case. The inner label is the one assigned by the originating PE router (PE1) for the VPN route, which is 1027.

On a Carrier's MPLS VPN Network, PE1 and PE2 Transmit