You can configure layer 2 services over MPLS to transmit data between two layer 2 interfaces that reside on the same E-series router. In this configuration, which is referred to as a local cross-connect, traffic that arrives at the router’s ingress interface is switched out the egress interface, instead of going through an MPLS core network.
A local cross-connect enables the router to function as a layer 2 switch. It operates with any supported layer 2 service. To configure local cross-connects, you must use the mpls-relay command.