Consistent update of distance vector routing hybrid SDN networks

Hybrid SDN networks are a transition between traditional networks and SDN networks. They can offer traditional services while achieving some SDN advantages such as better manageability. However, updates to hybrid SDN networks lack effective techniques, especially for the case where distance vector routing is involved. In this paper, we impose segment routing on updates to hybrid SDN networks, and formalize the application of segment routing in hybrid SDN networks. By combining ordered scheduling and two-phase commit, we propose the LFCA algorithm. The algorithm attempts to stitch the final path using segment routing and to install the routing information into the packet header first. Nevertheless, for flows that are not segmentable, the algorithm constructs the dynamic topology set that can react to the remote effect of updates, and evaluates every update operation by backtracking until it finds the longest consistent update sequence. Last, a two-phase commit mechanism is leveraged to update the remaining nodes. Our experiments verify that this algorithm can significantly save on rule overhead and time costs in comparison with prior techniques.