Valid Protocols for VPLS Signaling

CD

VPLS (Virtual Private LAN Service) is a Layer 2 VPN technology that allows multiple customer sites to be connected through a provider network as if they were on the same LAN segment. In order to set up and maintain VPLS connectivity, signaling protocols are used between the customer edge (CE) devices and the provider edge (PE) devices.

The following are the two valid protocols used to signal VPLS in a network:

1. BGP (Border Gateway Protocol): BGP is a widely used routing protocol that can also be used for signaling VPLS connections. When BGP is used for VPLS signaling, the PE routers exchange VPLS-related information, such as the VPLS instance ID, the MAC addresses of the CE devices, and the Ethernet VLAN IDs used to transport VPLS traffic. BGP can also be used to distribute VPLS routes across the network, providing an efficient way to scale VPLS deployments.

2. LDP (Label Distribution Protocol): LDP is a protocol used to distribute labels that identify network paths and forwarding actions in MPLS (Multiprotocol Label Switching) networks. In VPLS deployments, LDP can be used to signal VPLS connections between the CE and PE devices. LDP assigns a label to each VPLS connection and distributes it to the PE routers, which use it to forward VPLS traffic to the correct destination.

The other two options, CCC (Cisco CrossConnect) and RSVP (Resource Reservation Protocol), are not valid protocols for signaling VPLS in a network. CCC is a proprietary Cisco protocol used for connecting two Ethernet interfaces on the same router, while RSVP is a protocol used for reserving network resources for QoS (Quality of Service) purposes.