[Freeswitch-users] How to get the content of SIP headers and sdp in dialplan?

[Robert Dyck]

There should be no To tag with the initial INVITE. The tag is added by the 
callee per RFC3261.

On Wednesday 17 September 2008, Jon Bruel wrote:
> Mike, in my test setup, no tags are added to the To-header by the
> FreeSWITCH. The reason why I want to control it? Well, many phones uses
> the tag to relate an existing call to a NOTIFY message (send after the
> INVITE has been sent) with the same headers (and the same to-tag) as the
> INVITE. I'm not aware of how this functionality is described in the RFC,
> though.
>
> My aim is the check if I can use the FreeSWITCH to replicate a function
> known in BroadWorks. In this system, there are a number of plug-ins and
> web-interfaces which are used to control the SIP phone: Answer, put on
> hold and resume. The plug-in controls the application server through a
> XML interface, which in turn sends the NOTIFY to the phone. Thus the
> phone can be controlled without connectivity between the PC and the
> phone. These three states are controlled by a Notify message sent from
> the application server. So it would be useful to find a way of sending a
> Notify message to the phone from the FreeSWITCH. Other NOTIFY messages
> could be used for other useful things such as resetting the phone.