A bi-criteria algorithm for multipoint-to-multipoint virtual connections in transport networks

For a Carrier Ethernet or MPLS-TP service provider the determination of a multipoint-to-multipoint (mp2mp) virtual connection must be done in an efficient way in order to maximise network performance. This problem can be formulated as a Steiner tree problem which is a very complex combinatorial problem, being NP-complete. In general, any transport network ideal management system should seek to balance the load of the links while, at the same time, seeking to minimize the resources involved in each connection. In this work it is presented a bi-criteria formulation for the Steiner tree problem which includes these objectives. In order to solve this problem a heuristic was developed based on a known bi-criteria spanning tree algorithm that finds the set of efficient supported solutions in a given sub-graph. This new heuristic allows to obtain `good' compromise Steiner trees in an efficient manner. The obtained solution set contains some times the optimal solution for each objective included in the problem formulation. It is important to note that the analysis of the whole set of solutions may be important in some management transport network scenarios.