METHOD, SYSTEM AND ACCESS SERVICE ROUTER FOR IMPLEMENTING MULTICAST SERVICE

The present invention discloses a method for implementing multicast service, and the method includes: a multicast source sends multicast service packets, and sets the destination address of the multicast service packets to the Group Access Identity (GAID) assigned for the multicast source; the Access Service Router (ASR) which the multicast source belongs to, according to the GAID, searches for a corresponding Group Router Identity (GRID) in an established GAID-GRID mapping table, and sends the multicast service packets to a General Switch Router (GSR); the GSR searches for a corresponding multicast tree according to the GRID of the multicast service packets, and sends the multicast service packets to the ASR in the service area; the ASR in the service area, according to the GRID, searches for the corresponding GAID in the established GAID-GRID mapping table, and sends the multicast service packets to terminals under the ASR. The present invention also discloses a corresponding system and ASR. The present invention implements multicast in the locator/identity separation network.