Paging with Polycom Phones using Alert-Info.
Posted by , Last modified by on 12 April 2016 09:48 AM
What is Alert-Info and how can it be used for paging with Polycom IP Phones?
This blog details the necessary settings needed to make your Polycom IP Phones automatically pick up a page placed to it, with no user interaction. You can make your SIP phones auto answer by setting the Alert-Info variable in your PBX and modifying the XML configuration file.
Typically, all Polycom phones will retrieve their configuration files from a server on bootup. It is on this server where you will need to make modifications to the configuration files. These changes can be made in the 'sip.cfg' file located on the provisioning server or a customized configuration file used for provisioning. The filename is customizable so you may need to ask the Polycom phone administrator for its location and then possibly request the following changes are made.
Below is a modified config which will enable paging to Polycom phones with the ability to set the phone to auto-answer with ringer or without ringer.
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<!-- PlcmConversionCreatedFile version=1.2 converted=Tue Aug 23 16:59:18 2011 -->
<polycomConfig xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="polycomConfig.xsd">
<voIpProt.SIP.alertInfo voIpProt.SIP.alertInfo.1.class="ringAutoAnswer" voIpProt.SIP.alertInfo.1.value="Auto Answer"/> voIpProt.SIP.alertInfo.2.class="autoAnswer" voIpProt.SIP.alertInfo.2.value="answer"
You will then need your PBX to send the following in the INVITE.
Alert-Info: info=Auto Answer - This will ring then answer.
Alert-Info: info=Answer - This will just auto answer.