On the Practical Irrelevance of Metrics on Segment Routing Traffic Engineering optimization

摘要

Segment Routing (SR) based traffic engineering can be used to avoid network congestion effectively. Most research about SR considers the routing metric as a given constant. The metric defines shortest paths. As shortest paths are essential building blocks of SR paths, the metrics heavily influence SR. In this paper, we evaluate this influence thoroughly using data from a tier one Internet Service Provider (ISP) backbone, as well as other, publicly available topologies. We conclude that metrics do in fact play a role in SR optimization. Simple metrics, however, already push SR close to the optimum with respect to the most common traffic engineering objective of minimizing maximum utilization.