Method and apparatus for fast reroute in a connection-oriented network

A non-transitory computer-readable medium storing instructions, the instructions comprising:

• one or more instructions, which, when executed by a processor, cause the processor to:
• forward, from a first node, first packets according to a first route, of a plurality of different routes, the one or more instructions to forward the first packets including:
• one or more instructions to forward the first packets to a second node, of a plurality of nodes, that is downstream, along the first route, of the first node;
• determine failure of the second node;
• determine, upon determining that the second node has failed, if the first node stores information regarding the plurality of different routes;
• forward, upon determining that the first node stores the information regarding the plurality of different routes, second packets according to a second route, of the plurality of different routes,
• the second route not including the second node,
• the second route being created by merging a third route with a fourth route,
• the third route and the fourth route having similar constraints, and
• the third route and the fourth route having common node after which the third route and the fourth route share at least one node and at least one link,
• the second route being different from the first route, and
• the first packets and the second packets being associated with a same flow of packets;
• and
• transmit, from the first node and upon determining that the first node does not store the information regarding the plurality of different routes, a message to a third node,
• the third node being different than the second node.

A network node comprising:

• a processor to:
• forward first packets according to a first route, of a plurality of different routes, the processor, when forwarding the first packets, being further to:
• forward the first packets to a second network node, of a plurality of network nodes, that is downstream, along the first route, of the network node;
• determine that the second network node has failed;
• and
• determine, upon determining that the second node has failed, if the network node stores information regarding the plurality of different routes;
• forward, upon determining that the network node stores the information regarding the plurality of different routes, second packets according to a second route, of the plurality of different routes,
• the second route not including the second network node,
• the second route being created by merging a third route with a fourth route,
• the third route and the fourth route having similar constraints, and
• the third route and the fourth route having common node after which the third route and the fourth route share at least one node and at least one link,
• the second route being different from the first route, and
• the first packets and the second packets being associated with a same flow of packets;
• and
• transmit, upon determining that the first node does not store the information regarding the plurality of different routes, a message to a third node,
• the third node being different than the second node.