EchoRequest & EchoResponse

Echo is used to exchange information about latency, bandwidth and liveness. Echo request timeout indicates disconnection. If the OpenFlow implementation is multi-layered, Echo should be implemented in the lowest level (closest to kernel) as it might be used for debugging in some situations.
- Initiator
- Either
- Acknowledged
- Yes
Structure

EchoReq in this version has a header and optionally a variable length field, data, containing arbitrary information, such as latency (timestamp), bandwidth, liveness, etc. EchoRes shares the same structure with EchoReq. The EchoRes data is an exact copy of the data present from the corresponding EchoReq.
References
OpenFlow Switch Specification 1.0.0, pages 41Structure

No changes were made from OpenFlow 1.0.
References
OpenFlow Switch Specification 1.1.0, pages 55-56Structure

No changes were made from OpenFlow 1.0.
References
OpenFlow Switch Specification 1.2, pages 66Structure

No changes were made from OpenFlow 1.0.
References
OpenFlow Switch Specification 1.3.0, pages 84Structure

No changes were made from OpenFlow 1.0.
References
OpenFlow Switch Specification 1.3.1, pages 102Structure

No changes were made from OpenFlow 1.0.
References
OpenFlow Switch Specification 1.3.2, pages 104Structure

No changes were made from OpenFlow 1.0.
References
OpenFlow Switch Specification 1.3.3, pages 109Structure

No changes were made from OpenFlow 1.0.