VLAN tunneling protocol

摘要

A virtual local area network (VLAN) tunneling system includes an ingress edge switching node that adds VLAN encapsulation information to a packet even if the egress port is configured to act as an untagged 802.1Q port. The packet is tunneled via a label-switched path (LSP) according to a multiprotocol label switching (MPLS) protocol. Label values are used for identifying a next switching node in the LSP to which the packet is to be transmitted. At a penultimate switching node in the LSP, a current label value is replaced with a label value reserved for packets originating from a port associated with a VLAN. An egress switching node in the LSP receives the packet with the reserved label value and recognizes that VLAN information is embedded in the packet. The egress switching node extracts the embedded VLAN information as well as the original source and destination addresses, and processes the packet for transmitting to a final destination.