Hawkeye: Efficient In-band Network Telemetry with Hybrid Proactive-Passive Mechanism

With the rapid development of software-defined networking and programmable data plane, in-band network telemetry (INT) has attracted a lot of attention as an advanced network monitoring method. INT enables fine-grained and efficient network monitoring by encapsulating device status information into the packets. INT is divided into two types, proactive and passive, according to the source of the data packets carrying telemetry information. The proactive INT assembles large amounts of dedicated probe packets, with additional bandwidth overhead. The passive INT leverages the on-the-fly application flows, which saves the bandwidth cost but usually cannot achieve full coverage of network nodes. In this paper, we first propose a hybrid proactive-passive INT telemetry system, Hawkeye, which combines the proactive and passive INT methods together. Hawkeye leverages the advantages of the both methods and significantly saves the bandwidth cost while achieving telemetry coverage. To make it, Hawkeye divides the network topology into two parts, proactive INT network part and passive INT one, based on the historical traffic information. First, Hawkeye offloads passive telemetry tasks with the existing steady flows. Then, Hawkeye leverages a path planning algorithm, P2A, to generate the best possible probe paths to cover the rest of the network, which are not covered by passive telemetry. Simulation results show that Hawkeye can reduce the average bandwidth overheads by 55.2% and achieve 100% network link coverage for the real-world network topology, compared against the existing INT methods.