Propagation of routing information in rsvp-te for inter-domain te-lsps

An apparatus comprising:

• a processor;
• and
• a memory having stored therein instructions which, when executed by the processor, cause the processor to:
• receive routing information from a target node;
• determine, based on the received routing information, a set of one or more calculated routes reachable via a traffic engineering (TE) label switched path (LSP) to the target node, and a cost to reach the target node using each of the calculated routes;
• insert the calculated routes into a first routing table, and
• merge contents of the first routing table with contents on a second routing table at the apparatus, to yield an updated routing table.

A computer readable storage device having stored therein instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising:

• receiving routing information from a tail-end node;
• determining, based on the received routing information, a set of one or more calculated routes reachable via a traffic engineering (TE) label switched path (LSP) to the tail-end node, and a cost to reach the tail-end node using each of the calculated routes;
• inserting the calculated routes into a shadow routing table;
• and
• merging contents of the shadow routing table with routes in a different routing table to yield an updated routing table.

The computer readable storage device of 18, storing additional instructions which, when executed by the one or more processors, causes the one or more processors to perform operations comprising:

• receiving by a head-end node from the tail-end node, one or more unsolicited updates to the received routing information comprising changes to the received routing information;
• storing one or more routes calculated based on the changes to the received routing information, into the shadow routing table to yield an updated shadow table;
• and
• merging contents of the updated shadow table with contents stored in the updated routing table to yield a second updated routing table.