Co-iOAM: In-situ telemetry metadata transport for resource constrained networks within IETF standards framework

摘要

Providing reliable and continuous wireless connectivity during the operational phase of large-scale IoT deployments is a challenge for network operators. Conventional methods of acquiring network telemetry data using dedicated probe messages are costly in terms of additional bandwidth consumption, battery depletion, increased network congestion, leading to degraded application QoS. We propose an in-situ network telemetry transport mechanism, termed Co-iOAM (Telemetry in-situ Operations Administration and Maintenance), for monitoring and troubleshooting resource constrained 6LoWPAN/LPWAN networks, where telemetry data appended as metadata accompanying application packet at intermediate nodes. Further, cross-layer telemetry information support by Co-iOAM can be used for performance analysis of the path traversed by the application packets, network lifetime estimation, and network planning. The architectural and design objectives of Co-iOAM include, flexibility, light-weight operation, and cross-layer telemetry data and its optimized representation. We share the implementation aspects of the protocol on Contiki OS, and present the experimental results that exhibit relatively good scalability. We also propose context aware compression and simple distributed probabilistic update techniques to further reduce the byte overheads of Co-iOAM data while maintaining the quality of network monitoring.