1-4z Remote connection: A remote connection is established between a local CE and a remote CE,which are connected to different PEs. In this case, a static LSP is required to transport packetsfrom one PE to another.z Only remote connection is supported by S7900E Series Ethernet Switches.z You must configure for each remote CCC connection two LSPs, one for inbound and the other foroutbound, on the P device along the remote connection.SVC MPLS L2VPNStatic Virtual Circuit (SVC) also implements MPLS L2VPN by static configuration. It transfers L2VPNinformation without using any signaling protocol.The SVC method resembles the Martini method closely and is in fact a static implementation of theMartini method. The difference is that it does not use LDP to transfer Layer 2 VC and link information.You only need to configure VC label information.The labels for CCC and SVC range from 16 to 1023, which are reserved for static LSPs.Martini MPLS L2VPNThe key of the Martini method is to set up VCs between CEs. Pseudo wire that is the bidirectional virtualconnection between VSIs. A PW consists of two unidirectional MPLS virtual circuits (VCs).Martini MPLS L2VPN employs VC type and VC ID to identify a VC. The VC type indicates theencapsulation type of the VC, which can be VLAN,. The VC ID uniquely identifies the VC among theVCs of the same VC type on a PE.The PEs connecting the two CEs of a VC exchange VC labels through LDP, and bind their respectiveCE by the VC ID.Once LDP establishes an LSP between the two PEs and the label exchange and the binding to CE arefinished, a VC is set up and ready to transfer Layer 2 data.To allow the exchange of VC labels between PEs, the Martini method extended LDP by adding theforwarding equivalence class (FEC) type of VC FEC. Moreover, as the two PEs exchanging VC labelsmay not be connected directly, a remote LDP session must be set up to transfer the VC FEC and VClabels.With Martini MPLS L2VPN, only PEs need to maintain a small amount of VC labels and LSP mappingsand no P device contains Layer 2 VPN information. Therefore, it has high scalability. In addition, to adda new VC, you only need to configure a one-way VC for each of the PEs. Your configuration will notaffect the operation of the network.
