DUNDi™ is a peer-to-peer system for locating Internet gateways to telephony services. Unlike ENUM, which is strictly hierarchical since it is based on DNS, DUNDi does not enforce any particular network architecture, and the protocol is designed to adapt to whatever architecture it is given.

However, in the interest of preserving the usefulness of the system, it is valuable to build the network as an m-ary tree. If you are interested in joining the DUNDi E.164 trust group, you will need to execute the General Peering Agreement (GPA™) with an existing member of the E.164 Trust Group. It is generally optimal to peer with another member who is already representing numbers most similar to your numbers (starting left to right). If you cannot find any other members of the trust group, you can contact one of the core members and they can help you find a member with which to peer. Generally, the further out from the center of the ring, the lower the bandwidth required to handle the number of queries.

Entity	Description	Contact	Prefixes
Asterlink	IAX/SIP Termination and Tollfree		18,17
Digium, Inc.	Primary Sponsor of Asterisk		12
Free World Dialup (pulver.com)	Free SIP and IAX registration
NuFone, Inc.	IAX and SIP Internet Telephony Service Provider
SIPphone	SIP Service Provider
Telesthetic, LLC	Michigan Competitive Local Exchange Carrier
VoicePulse, Inc.	IAX and SIP Internet Telephony Service Provider
SpeakUp	Dutch VoIP Service and Solution Provider		31
Tier Two
Entity	Description	Contact	Prefixes

This section of the web site should be updated as more best practices are discovered.