Yu-Wei Sung (Purdue University, US); Sanjay Rao (Purdue University, US); Geoffrey Xie (Naval Postgraduate School, US); David Maltz (Microsoft Research, US)
Enterprise networks are important, with size and complexity even surpassing carrier networks. Yet, the design of enterprise networks is ad-hoc and poorly understood. In this paper, we show how a systematic design approach can handle two key areas of enterprise design: VLANs and reachability control. We focus on these tasks given their complexity, prevalence, and time-consuming nature. Our contributions are three-fold. First, we show how these design tasks may be formulated in terms of network-wide performance, security, and resilience requirements. Our formulations capture the correctness and feasibility constraints on the design, and they model each task as one of optimizing desired criteria subject to the constraints. The optimization criteria may further be customized to meet operator-preferred design strategies. Second, we develop a set of algorithms to solve the problems that we formulate. Third, we demonstrate the feasibility and value of our systematic design approach through validation on a large-scale campus network with hundreds of routers and VLANs.