There are two service models for GMPLS. Each model determines how much visibility a client node, such as a router, has into the optical core or transport network. The first model is a UNI, which is often referred to as the overlay model. The second is known as the peer model. Juniper Networks supports both models.
peer-interface can be used after you have configured the LMP peers, it is needed to add the peer interfaces to RSVP and OSPF. The peer interface name must match the peer name configured in LMP. Once the peer interfaces are added to the protocols, the TE link local and remote addresses can be signaled and advertised to peers like any other interface enabled for RSVP and OSPF. These act as virtual interfaces for GMPLS.
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