Distributed Universal Number Discovery (DUNDi) is a VoIP routing protocol that provides directory services similar to what is provided by ENUM.DUNDi allows peered nodes to share dialplan information with each other. It does not actually carry any calls, but rather provides addressing information. In simple terms, it is like asking your neighbouring peer whether he knows how to reach a certain phone-extension or VoIP client. Some sort of P2P phonebook.