
Configuring Basic Features
261
2.
Select the desired value from the pull-down list of Accept SIP Trust Server Only.
3.
Click Confirm to accept the change.
Call completion allows users to monitor the busy party and establish a call when the
busy party becomes available to receive a call. Two factors commonly prevent a call
from connecting successfully:
Callee does not answer
Callee actively rejects the incoming call before answering
IP phones support call completion using the SUBSCRIBE/NOTIFY method, which is
specified in draft-poetzl-sipping-call-completion-00, to subscribe to the busy party and
receive notifications of their status changes.
The caller subscribes for update notifications of the dialog event from the busy party.
Example of a SUBSCRIBE message:
SUBSCRIBE sip:[email protected]:5060 SIP/2.0
Via: SIP/2.0/UDP 10.10.20.32:5060;branch=z9hG4bK2880274891
From: "10111" <sip:[email protected]:5060>;tag=8643512
To: <sip:[email protected]:5060>;tag=4025601441
Call-ID: [email protected]
CSeq: 2 SUBSCRIBE
Contact: <sip:[email protected]:5060>
Accept: application/dialog-info+xml
Max-Forwards: 70
User-Agent: Yealink SIP-T23G 44.80.0.60
Expires: 60
Event: dialog
Summary of Contents for Yealink SIP-T42G
Page 1: ......
Page 12: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series CP860 IP Phones xii ...
Page 20: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series CP860 IP Phones xx ...
Page 41: ...Getting Started 21 For SIP T46G Desk Mount Method Wall Mount Method Optional ...
Page 43: ...Getting Started 23 For SIP T29G T27P Desk Mount Method Wall Mount Method Optional ...
Page 45: ...Getting Started 25 For SIP T21 P E2 Desk Mount Method Wall Mount Method Optional ...
Page 678: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series CP860 IP Phones 658 ...