Yealink T48G, Administrator'S Manual

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Administrator’s Guide for SIP-T2 Series/T4 Series/T5 Series IP Phones
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soft key on the phone to allow remote control. You can specify one or more trusted IP addresses on the
IP phone, or configure the IP phone to receive and handle the URI from any IP address.
Supported SIP Notify Message
In addition, Yealink IP phones can perform the specified action immediately by accepting a SIP NOTIFY
message with the “Event: ACTION-URI” header from a SIP proxy server. The message body of the SIP
NOTIFY message may contain variable named as “key” and variable value, which are separated by “=”.
This method is especially useful for users who always work in the small office/home office where a secure
firewall may prevent the HTTP or HTTPS GET request from the external network.
Note
If you want to only accept the SIP NOTIFY message from your SIP server and outbound proxy server, you
have to enable the Accept SIP Trust Server Only feature. For more information, refer to
Accept SIP Trust
Server Only .
If you use SIP NOTIFY message method, you do not need to specify the trusted IP address for action URI.
However, you should enable the IP phone to receive the action URI requests. When the IP phone receives
a SIP NOTIFY message with the “Event: ACTION-URI” header from a SIP proxy server for the first time, the
LCD screen also prompts the message “Allow remote control?”. Press the OK soft key on the phone to
allow remote control.
Example of a SIP Notify with the variable value (OK):
Message Header
NOTIFY sip:3583@10.2.40.10:5062 SIP/2.0
Via: SIP/2.0/UDP 10.2.40.27:5063;branch=z9hG4bK4163876675
From: <sip:3586@10.2.1.48>;tag=2900480538
To: "3583" <sip:3583@10.2.1.48>;tag=490600926
Call-ID: 2923387519@10.2.40.10
CSeq: 4 NOTIFY
Contact: <sip:3586@10.2.40.27:5063>
Max-Forwards: 70
User-Agent: Yealink SIP-T46G
Event: ACTION-URI
Content-Type: message/sipfrag
Content-Length: 6
Message Body
key=OK