Multicast packet forwarding method, apparatus and multicast system

A multicast packet forwarding apparatus in a network node within a network domain, comprising:

• a multicast packet receiving unit, adapted to receive a multicast packet of a multicast group;
• an information determination unit, adapted to determine node information about egress nodes that the multicast packet needs to reach, wherein the egress nodes that need to be reached comprise the egress nodes successfully joining in the multicast group;
• and
• a multicast packet forwarding unit, adapted to add, according to the information, determined by the information determination unit and about all the egress nodes that are downstream nodes of the network node and that the multicast packet needs to reach, the node information about the egress nodes that the multicast packet needs to reach, into the multicast packet, and send the multicast packet carrying the node information about the egress nodes.

A multicast system, comprising:

• an ingress node, adapted to receive a multicast packet, determine information about all egress nodes of the multicast packet in a network domain, and forward the multicast packet according to the information about all the egress nodes in the network domain;
• intermediate nodes, adapted to receive the multicast packet sent by the ingress node or the adjacent upstream intermediate nodes, determine the information, about all the egress nodes of the multicast packet that are downstream nodes of the intermediate nodes and that the multicast packet needs to reach, and forward the multicast packet according to the information about all the egress nodes of the multicast packet that are downstream nodes of the intermediate nodes and that the multicast packet needs to reach;
• and
• the egress nodes, adapted to receive the multicast packet sent by the adjacent upstream intermediate nodes.