Enterprise Leased Line Interconnections
On the network shown in Figure 1, an enterprise has two sites in different places. Each site has three networks: finance, marketing, and others. To ensure network security, users of different networks cannot communicate with each other.
A carrier deploys the VPLS technology on the IP/MPLS core network and QinQ on the ME network. Three VLANs are assigned for each site to identify the finance, marketing and other departments, and the VLAN ID for finance is 100, for marketing is 200, and for others is 300. An outer VLAN 1000 is encapsulated on a UPE (Packets can be added with different VLAN tags on different UPEs). The sub-interface bound to a VSI on the NPE connected to the UPE is in symmetry mode. In this way, users belonging to the same VLAN in different sites can communicate with each other.