Disclosed are a
processing method and related device for a host
route in a virtual sub-network, and a communication
system. The
processing method for a host
route in a virtual sub-network comprises: receiving, by a first operator
edge device, a packet used for address
parsing, wherein at least one second operator
edge device is also included in a virtual sub-network
station where the first operator
edge device is located; determining, by the first operator edge device, whether a source
MAC address carried in the packet is a virtual
MAC address; and if it is determined that the source
MAC address is a virtual MAC address, not executing at least one of the following operations: saving a table entry of a local
customer edge (CE) host
route corresponding to a source
IP address carried in the packet, and distributing the local CE host route corresponding to the
IP address in a virtual sub-network based on a
routing protocol of a layer 3 VPN. The solution in the embodiments of the present invention is beneficial to avoid forming CE host route loops as far as possible, thus improving the efficiency of data
packet transmission between CE hosts.