Method and apparatus for forwarding network traffic on maximally disjoint paths

A network element for forwarding network traffic from multiple sources to multiple destinations on maximally disjoint paths by maximally redundant trees, MRTs, implementing multipoint-to-multipoint functionalities in a path computation element, PCE, of a network, the network having a plurality of network elements, the network element comprising:

• a processor;
• and
• a memory, the memory comprising instructions executable by the processor whereby the network element is configured to:
• compute an almost directed acyclic graph, ADAG, for the network, the ADAG being a graph abstraction of the network, the plurality of network elements being the vertices of the ADAG and links connecting the plurality of network elements are the directed edges of the ADAG, the ADAG having an arbitrary root;
• compute next hops along MRTs using the ADAG;
• determine at least one valid path pair of the computed MRTs that is disjoint;
• and
• forward network traffic using the valid path pair(s) of the MRTs.

A computer storage medium storing a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to perform a method according to for forwarding network traffic from multiple sources to multiple destinations on maximally disjoint paths by maximally redundant trees, MRTs, implemented in a network element implementing multipoint-to-multipoint functionalities in a path computation element, PCE, of a network, the network having a plurality of network elements, the method comprising:

• computing an almost directed acyclic graph, ADAG, for the network, the ADAG being a graph abstraction of the network, the plurality of network elements being the vertices of the ADAG and links connecting the plurality of network elements are the directed edges of the ADAG, the ADAG having an arbitrary root;
• computing, by the network element, next hops along MRTs using the ADAG;
• determining at least one valid path pair of the computed MRTs that is disjoint;
• and
• forwarding network traffic using the valid path pair(s) of the MRTs.