Heterogeneous VPWS
On a heterogeneous VPWS network, a VC is established between CEs of different link types, and AC interfaces are enabled with IP interworking to transparently transmit Layer 3 data, that is, IP packets, over an MPLS network.
If the link types of CEs on both ends of an L2VPN link are different, the heterogeneous VPWS feature is required.
Introduction
Heterogeneous VPWS is used when the link types of CEs on both ends of an L2VPN link are different. After a PE on a heterogeneous VPWS network receives a frame from a CE, the PE removes the frame header and transparently transmits the IP packet over an MPLS network to the peer PE. The peer PE re-encapsulates the IP packet according to its link-layer protocol and transmits the packet to the connected CE. The link-layer control packet sent by a CE is processed by the corresponding PE and is not transmitted over the MPLS network. All non-IP packets, such as MPLS and Internet Packet Exchange (IPX) packets, are discarded.
Heterogeneous VPWS Network Topology
If heterogeneous sites access an L2VPN backbone network, heterogeneous VPWS must be configured. On the network shown in Figure 1, Site 3 and Site 4 access the L2VPN backbone network by the same means, but Site 1 and Site 2 access the L2VPN backbone network by different means.
