Abstract
A software-defined network (SDN) controller and a multipath routing method are provided. In the method, a maximum bottleneck bandwidth (MBB) and a minimum hop count (MHC) of each of the nodes in the SDN are first initiated. Next, a source node is visited and neighboring nodes thereof are discovered so as to relax paths between the source node and each of the neighboring nodes. Then, a forwarding node having a maximum MBB among other nodes is visited and its neighboring nodes which are unvisited are discovered so as to relax paths between the forwarding node and each of the neighboring nodes. Afterwards, the rest nodes are consecutively visited until all nodes are visited. Finally, a disjoint path lookup table is established according to relation between the paths recorded for each node and accordinglykdisjoint paths having the maximum bottleneck bandwidth are founded for transmittingksub-flows divided from a data flow.