Highly-Efficient and Adaptive Network Monitoring: When INT Meets Segment Routing

The rapid development of software-defined networking (SDN) has promoted the idea of programmable data plane (PDP), which opens up unprecedented opportunities for realizing powerful and timely network monitoring. This work explores the advantages of PDP to merge two famous techniques (i.e., the segment routing (SR) and in-band network telemetry (INT)) seamlessly for highly-efficient and adaptive network monitoring. Specifically, by leveraging the protocol-oblivious forwarding (POF), we propose SR-INT, which time-multiplexes the header fields in each packet for INT and SR, and keeps packet length constant end-to-end even though both INT and SR are used. Hence, our proposal can enjoy the benefits of INT and SR, while avoiding the accumulated overheads due to simultaneous usage. We design the packet format of SR-INT, and lay out its packet processing procedure to guarantee that the configuration of SR-INT can be adjusted dynamically to adapt to the requirements of network monitoring. We implement and experimentally demonstrate SR-INT in a POF-based SDN environment. Our results show that SR-INT not only reduces the bandwidth overheads of using SR and INT simultaneously but also simplifies the operations in software-based POF switches.