CATENAE: A scalable service function chaining system for legacy mobile networks

Service function chaining promises to ease the introduction of new services in mobile networks by enabling the dynamic composition of virtualized network functions. However, current implementations rely on new tunneling protocols and on network infrastructure changes, which make deployments in legacy networks difficult. In this paper, we present a system for service function chaining that can be readily deployed in mobile networks, without requiring any protocols or network modifications. Our system, named CATENAE, exploits the specific properties of the targeted deployment environment to overcome scalability issues and efficiently implement traffic steering. Using a centralized controller, CATENAE coordinates software‐defined networking software switches to implement a steering method based on MAC address rewriting. Furthermore, we present the design of a hybrid hardware‐software software‐defined networking switch to realize a scalable network traffic classifiers, which CATENAE employs to assign network flows to corresponding function chains. Using experimental evaluations based on physical testbeds, emulated environments, and simulations, we demonstrate that our approach is ready to be deployed in mobile networks, scales to handle expected mobile networks' workloads, introduces no overhead in the (virtual) network functions, and integrates seamlessly with legacy network management systems.