Technique for protecting leaf nodes of a point-to-multipoint tree in a communications network in connected mode

摘要

A technique protects, in a communications network, a point-to-multipoint primary tree between a root node and primary leaf nodes of the network if a failure occurs affecting one of the primary leaf nodes. One network node receives from another upstream network node a request to protect the primary tree via a backup branch leading to a backup leaf node situated downstream from said node, if a failure affecting one of the primary leaf nodes to be protected occurs, the backup leaf node being associated with the primary leaf node to be protected. If the node is connected directly to the downstream primary leaf node to be protected, it configures a backup routing rule for routing packets from an upstream primary branch to the downstream backup branch and, possibly, to the downstream primary branch(es) and is activated in the event of a failure affecting the primary leaf node to be protected.

主权项

1. A method of protecting, in a communications network in connected mode, a point-to-multipoint primary tree comprising a root node and primary leaf nodes of the network, said primary leaf nodes having no child nodes in the network, in the event of a failure at one of the primary leaf nodes, including the following steps executed by a node of the network:
receiving from another network node a request to protect the primary tree by at least one backup branch leading to a backup leaf node having no child node and situated downstream from said another node in the network in an event of a failure affecting at least one of the primary leaf nodes to be protected, the backup leaf node being associated with the primary leaf node to be protected; if the node is upstream from at least one backup leaf node, configuring at least one activated secondary routing rule to route packets coming from an upstream backup branch to the downstream backup branch and, where appropriate, to downstream primary branches; and if the node is connected directly to the downstream primary leaf node to be protected, configuring a backup routing rule to route packets from an upstream primary branch leading to a downstream backup branch and, if appropriate, to a primary downstream branch or branches that is activated in an event of a failure affecting said primary leaf node to be protected.