[SIPForum-discussion] Dynamically enable and disable Call Forwarding from a VoIP Phone

[sreekant nair]

Hello,

I am trying to implement the most common three flavors of Call Forwarding (Call Forward Busy- CFB, Call Forward No Answer - CFNA and Call Forward Unconditional - CFU)

The first two are relatively straight forward with some involvement from the User Agent and proxy  during the actual call event. 

However, when it comes to CFU, all the literature ( in OpenSER and http://www.tech-invite.com/Ti-sip-service-7.html etc) points to the Proxy being pre-configured with the information that any incoming call to User X must be forwarded to User Y. This is fine when it comes to the actual call signalling/messaging. 

However, how is it set in the first place within the proxy. Is there a method of doing this other than by for e.g. the proxy administrator manually? Can a SIP User Agent enable/disable call forwarding at the proxy using SIP signalling. To give a clearer picture - on my cell phone, I can enable/disable call forwarding for some period of time. When we do this, the service provider's MSC/HLR is updated with this information so that the call is automatically routed to the forwarded number. This call flow is very clearly explained in the  lint of Call Forwarding Unconditional at "http://www.tech-invite.com/Ti-sip-service-7.html". It does not explain how the feature is enabled.

Is using the "forwarding number/URI" in the Contact of the REGISTER message an industry accepted practice? Is there any other way without involving the phone so that proxy has prior knowledge and it is dynamic?

All ideas are welcome. 

Thanks
Sreekant Nair


      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20090130/5457bf42/attachment-0002.html>