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<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>We are looking at how to implement some “Click to Dial”
functionality, and have come across a “REFER based” method
documented on several sites, e.g. <a
href="http://www.tech-invite.com/Ti-sip-service-19.html">http://www.tech-invite.com/Ti-sip-service-19.html</a>,
which shows the possibility of a Switch or some other agent sending a SIP REFER
to a Client which causes that client to make an outbound call to the “referred
to” URI.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>This is also documented elsewhere as:-<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>“First, the SIP server sends an </span><b><span
style='font-size:10.0pt;font-family:"Bembo-Bold","serif"'>INVITE </span></b><span
style='font-size:10.0pt;font-family:"Bembo","serif"'>to one of the phones
because phones usually do not accept<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><b><span style='font-size:10.0pt;
font-family:"Bembo-Bold","serif"'>REFER </span></b><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>without prior invitation.The </span><b><span
style='font-size:10.0pt;font-family:"Bembo-Bold","serif"'>INVITE </span></b><span
style='font-size:10.0pt;font-family:"Bembo","serif"'>contains 0.0.0.0 as the IP
address in SDP, because<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>there is no remote phone (the message is sent by
user agent within the SIP server which does not<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>deal with media).<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>After that, the server sends a </span><b><span
style='font-size:10.0pt;font-family:"Bembo-Bold","serif"'>REFER </span></b><span
style='font-size:10.0pt;font-family:"Bembo","serif"'>method which will ask the
phone to send </span><b><span style='font-size:10.0pt;font-family:"Bembo-Bold","serif"'>INVITE<o:p></o:p></span></b></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>somewhere else.The URI of the called party is
passed to the phone in a </span><b><span style='font-size:10.0pt;font-family:
"Bembo-Bold","serif"'>Refer-To </span></b><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>header field of<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>the </span><b><span style='font-size:10.0pt;
font-family:"Bembo-Bold","serif"'>REFER </span></b><span style='font-size:10.0pt;
font-family:"Bembo","serif"'>method.”<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Bembo","serif"'><o:p> </o:p></span></p>
<p class=MsoNormal>My question relates to whether or not it is possible to cause
FS to issue this form of REFER via the Event Socket interface to implement this
kind of click to dial functionality.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Rgds,<o:p></o:p></p>
<p class=MsoNormal>Neil<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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