User`s guide

SIP Extensions

1. Support PRACK method: enable SIP PRACK support.

2. Encode SIP URI with user parameter: encode user=phone parameter in

SIP URI.

3. Send INVITE with Timer header: encode Timer header in all INVITE

requests for ringing timeout

4. SIP session timer: enable SIP session timer function.

5. Conditional Call Forwarding Timer: Forward the call to the pre-

configured number if the phone does not pick up within the timer.

6. Disable Call Waiting: don’t play call waiting tone.

7. Disable Caller-ID display: don’t send out caller-id display for

incoming calls.

8. Call Hold using C=0.0.0.0: using the call hold method described in rfc 2543.

If unchecked, the call hold would follow rfc 3263 method

9. Send NOTIFY : send out NOTIFY request to transferer for unattended and

attended call transfer.