Feasibility of Compound Chained Network Functions for Flexible Packet Processing

The paper discusses and evaluates different implementation options of Service Function Chaining (SFC) in virtual computing environments. Classical SFC relies on dedicated virtual machines for each chained network function. The motivation is to increase the efficiency of the classical SFC approach with respect to latency and throughput. Therefore, compound SFC that are implemented in single virtual machines are proposed. The focus is on the evaluation of the latency of communication between network functions and on the impact of limited computing resources on the maximal executable workload. To evaluate the presented SFC concepts, the performance measurements in a hardware testbed using different network functions have been carried out. A prototype of compound SFC was implemented based on the networking toolkit Snabb [1]. Furthermore, a configurable synthetic network function was implemented and tested. The results show the sensitivity of different parameters with respect to the efficiency of SFC implementation options. Keywords— Service Function Chaining; Packet Processing; Virtualization; Latency; Resource Contention