DUNDi is a peer-to-peer system for locating Internet gateways to telephony services. Unlike traditional centralized services (such as the remarkably simple and concise ENUM standard), DUNDi is fully-distributed with no centralized authority whatsoever.

DUNDi is not itself a Voice-over IP signaling or media protocol. Instead, it publishes routes which are in turn accessed via industry standard protocols such as IAX, SIP and H.323.

References

DUNDi is documented at http://www.dundi.com
Implemented in pbx_dundi.c and dundi-parser.c
Configuration in dundi.conf