BPv7 Echo Service

This document specifies an echo service for Bundle Protocol Version 7 (BPv7) networks. The echo service receives bundles at a well-known endpoint and reflects them back to the originator, making only the minimal changes necessary to route the response. This enables round- trip time measurement and end-to-end connectivity verification in Delay-Tolerant Networks. This document requests IANA allocation of a well-known IPN service number and DTN demux for the echo service.