Automated IP Prefix Assignment Optimized for Enterprise Networks

The IP prefix assignment scheme has a significant impact on the efficiency and cost of an enterprise network, as it has a direct impact on the size of router forwarding tables. Large tables increase hardware requirements while exacerbating power and heat issues. Yet, prefix assignment today is still largely performed by hand and in an ad hoc manner, which is tedious and error-prone given the scale of modern enterprise networks, and often leads to unnecessarily large forwarding tables. This paper presents a novel algorithm for IP prefix assignment in enterprise networks. Our approach leverages key properties of enterprise routing design, such as the largely tree-structured topology and the prevalent use of default routes, to systematically optimize prefix aggregation and minimize router forwarding table sizes, while also ensuring the algorithm remains highly efficient. Furthermore, we provide a formal analysis establishing the optimality of the algorithm in the modeled enterprise settings. Together, these contributions offer a principled foundation for automated and scalable prefix assignment in enterprise networks.