High Performance Delay Monitoring for SRv6 Based SD-WANs

Typical enterprises have multiple geographically dispersed branch offices. These branches host the users that need to access the applications hosted in data centers. A Software-Defined Wide Area Network (SD-WAN) interconnects the branch offices with the data centers. We focus on SD-WAN services based on the Segment Routing over IPv6 (SRv6) technology. Performance Monitoring solutions are strongly required to detect performance degradation and outages, and optimize networks. In this paper, we describe a high performance solution for end-to-end delay monitoring for SRv6 based SD-WAN services. The presented solution leverages the Simple Two-way Active Measurement Protocol (STAMP) and its extensions to monitor the delay of an SRv6 path between two nodes called STAMP Session-Sender and Session-Reflector. We describe three implementations of the STAMP Session-Sender and Session-Reflector, two are based on user space processing and one based on eBPF. We compare the performance of our implementations. The results show that the eBPF-based implementation outperforms the user space implementations and has a negligible impact on user traffic.