Comments
Registrar:
The registrar server enables clients to alter the address at which they can be contacted.
A SIP client can send a REGISTER request to inform the registrar about the change in
the address. The registrar accepts the change and records the user's new address. Thus,
the information about the client's location is kept updated, even though the client
changes locations in the network. The registrar server also supports authentication.
A client must register with the registrar server each time a user turns on the SIP user
client, using a SIP IP phone, PC, laptop, or other SIP devices. Typically, the proxy or
registration server forwards the registration information to the location or the redirect
server. These registrations can occur at any time during a session and are also
periodically refreshed so that most recent information is stored in the location or the
redirect server. Therefore, a registrar server is co-located with a proxy or redirect server
to offer the location services.
Posted by sagitraz
• Preconfiguration- IP address is entered into the UA. Usually there are two, a primary and secondary.
• Address-of-Record – The host server. For instance, the Address of Record for UA sip:d.k@kusuary.com would be sip:kusuary.com
• Multicast – Contacts a central authority on the local net either by standard URL or by standard IP address.
Posted by george99
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