| 摘要 |
A communication method of the SMF type for a network of nodes including a multicast group. The method includes the steps, performed by a first node, of: determining a set of respective multipoint relays; determining the nodes for which the first node is a multipoint relay; determining a routing table including identifiers of destination nodes and corresponding identifiers of next-hop nodes; receiving a multicast packet sent from a sending node, where the first node is a multipoint relay; checking if, for each node identifier of the multicast group, the entry in the routing table that includes a destination node identifier corresponding to the node identifier of the multicast group contains a next-hop node identifier that corresponds to the sending node, and if the counter contained in the multicast packet respects a relation with a limit; and determining whether to retransmit the multicast packet, on the basis of the outcome of the checking step. |
| 主权项 |
1. A communication method of the Simple Multicast Forwarding (SMF) type for a network (1) including a plurality of nodes (2), which form at least one multicast group, said method comprising the steps, performed by a first node, of:
determining (7a), among the neighbouring nodes, a respective set of multipoint relays; determining (7b), among the neighbouring nodes, the nodes for which the first node is a respective multipoint relay; determining (8) a respective routing table, formed by a plurality of entries, each entry comprising an identifier of a corresponding destination node and an identifier of a next-hop node, said next-hop node neighbouring the first node and being a multipoint relay of the first node, and the destination node being connected to the first node through the next-hop node;said method further comprising the steps, performed by the first node, of:
determining (9) a set of identifiers of the nodes that belong to the multicast group; and receiving (10) a multicast packet sent by a sending node neighbouring the first node, and containing a counter;said method further comprising, if the first node is a multipoint relay of the sending node, performing, by the first node, a step of checking (22,30,42):
if at least one node identifier belonging to the multicast group exists for which the routing table entry of the first node that includes a destination node identifier corresponding to said at least one identifier contains a next-hop node identifier corresponding to the identifier of a node different from the sending node; and if the counter contained in the received multicast packet respects a predetermined mathematical relation with a limit value;said method further comprising, if the first node is a multipoint relay of the sending node, determining (30;42), by the first node, whether to perform a step of retransmitting (44) the multicast packet, based on the outcome of said checking step. |
