METHOD FOR PAIRING A FORWARDING EQUIVALENCE CLASS WITH AN INPUT LABEL AND AN OUTPUT LABEL, AT A ROUTER, AND RELATED ROUTER

摘要

The invention concerns a method whereby the FEC and a first associated label (L2) having been announced, in accordance with LDP, to the router (ABR2) by a downstream router, said router (ABR2) executes the following searching steps in a routing table (10) so as to identify an IP route corresponding to the announced FEC: extracting from the routing table (10) an output interface (Y) corresponding to the IP route identified as corresponding to the announced FEC, inserting in a switching table (20) the first label (L2), announced by LDP, as output label, coupled to the output interface (Y) extracted from the routing table (10), allocating the second label, as input label, to the announced FEC, in accordance with the allocation mode defined by LDP, and announcing the FEC and the second label associated with an upstream router. The invention is characterized in that, in the case where the routing table (10) does not contain any route identical to the FEC announced in accordance with LDP by the downstream router, the step of searching in the routing table (10) consists in identifying an IP route more global than the announced FEC and including the latter, said more global IP route thus identified being considered as corresponding to the FEC announced by LDP for executing the step of extracting an output interface from the routing table (10).