Another way to unify sites is by using Distributed Universal Number Discovery (DUNDI). DUNDi is a peer-to-peer routing protocol that helps us share information about the extensions, dialplans, services, contexts, and other resources across a neighborhood of VoIP servers with each other. It uses the RSA encryption standard to communicate between peers, and it runs on port 4520/UDP and the ENUM standard. With DUNDI, we can do the following:
Create a directory of local extensions and PSTN numbers that will be available to all peers.
Search within this directory for a number to see if it is available locally or remotely in another server until it is found.
If we make a change in one peer's dialplan, we do not need to declare a new route or extension in the other peers or servers.
Avoid the use of SIP/IAX trunks between the peers.
Avoid the use of a master server and its slaves.
Implement it using Elastix's WebGUI or Asterisk's configuration files.
Implement a multisite...