Optimizing Stateful Service Function Chaining on PDP Switches with Table Merging

The rapid development of network function virtualization (NFV) has notably increased the implementation of virtual network functions (vNFs), especially the stateful ones, on high-performance programmable data plane (PDP) switches (e.g., those based on P4 and Tofino ASICs). This facilitates offloading stateful service function chains (SFCs) to PDP switches. However, the capability of PDP switches to carry stateful SFCs is still constrained by their limited hardware resources. In this work, we propose to address this issue with adaptive table merging, formulate an integer linear programming (ILP) model to optimize the deployment of stateful SFCs on P4-based PDP switches with table merging, and design a time-efficient heuristic to solve the problem quickly. Simulation results validate that our proposals successfully enhance the deployment efficiency of stateful SFCs, outperforming existing benchmarks significantly.