Optimized Segment Routing Traffic Engineering with Multiple Segments

Network traffic balancing plays a key role in improving network performance. Recently, a new source routing technology, segment routing (SR), has been proposed to increase the network programming ability. SR expresses an end-to-end logical path as a sequence of segments, each of which represents the shortest path between its upstream node and downstream node. This new routing mechanism calls for a new traffic engineering method, i.e., Segment Routing Traffic Engineering (SRTE). In this paper, we devote ourselves to leveraging SRv6 to steer multiple flows in the network with the goal of minimizing the bandwidth utilization of the most congested link. Different from existing methods, we do not limit the number of available segments. We formulate this problem as an integer programming model. After proving the NP-hardness of this problem, we propose an efficient algorithm based on restricted widest paths. Comprehensive experimental results show that our method realizes similar routing performance as the optimal method while reducing the computation time by orders of magnitude.