DeltaINT: Toward General In-band Network Telemetry with Extremely Low Bandwidth Overhead

In-band network telemetry (INT) enriches network management at scale through the embedding of complete device-internal states into each packet along its forwarding path, yet such embedding of INT information also incurs significant band-width overhead in the data plane. We propose DeltaINT, a general INT framework that achieves extremely low bandwidth overhead and supports various packet-level and flow-level applications in network management. DeltaINT builds on the insight that state changes are often negligible at most time, so it embeds a state into a packet only when the state change is deemed significant. We theoretically derive the time/space complexities and the bounds of bandwidth mitigation for DeltaINT. We implement DeltaINT in both software and P4. Our evaluation shows that DeltaINT reduces up to 93% of INT bandwidth, and its deployment in a Barefoot Tofino switch incurs limited hardware resource usage.