A Framework for Network Function Decomposition and Deployment

Network Function Virtualization (NFV) enables fast provisioning of packet processing logic on general purpose CPUs. This approach, however, does not scale well to very high speed traffic. Programmable hardware solutions, including those based on programmable switches, are emerging as an option for accelerating and scaling network functions. Unfortunately, every type of programmable hardware has specific characteristics that do not make it suitable for running all possible functions. We argue that an efficient strategy is decomposing network functions into components that can run on CPUs or that can be offloaded to specific programmable hardware depending on their characteristics. This paper presents a preliminary work on a framework for automating the decomposition and deployment of network functions. The framework includes an orchestrator that chooses the best decomposition according to the traffic demands, the network topology and other constraints. It also provides a tool to combine multiple functions into a single P4 program that can be deployed to a programmable switch. Finally, the framework comprises a set of tools to deploy the network functions either as containers running in a data center or as programs loaded in a programmable switch. We present numerical results to highlight the advantages of partially offloading decomposed VNFs to programmable hardware over a pure software solution. We also highlight the robustness of the approach showing how the model reacts in case of network failures.