Minimum coding nodes multicast tree for two-channel all optical network coding scheme

A heuristic algorithm of establishing a minimum coding nodes multicast tree on which a two-channel all-optical network coding scheme can be performed is presented. To minimize the coding nodes, the heuristic graph-search control strategies are investigated. Firstly, a minimum relatedness principle is proposed to balance and minimize the out-degrees of the conventionally directed multicast tree. Secondly, a set of rules about bottom-up path search are presented to recover another path in the conventionally directed multicast tree, and a conflict-backtracking principle is given to minimize the coding nodes in this process. To evaluate the algorithm, some results are given. The results indicate that the algorithm can perform the expected function. Moreover, to further test and verify the algorithm, performances of different multicast modes are compared and analyzed. The results show that the multicast performances will be impaired if a multicast tree contains redundant coding nodes.