In-band network telemetry (INT) enriches network management at scale through the embedding of complete deviceinternal states into each packet along its forwarding path, yet such embedding of INT information also incurs significant bandwidth 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.