<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 14 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">So in this case CUCM sends the 183 Session Progress with SDP. We would then expect the Vidyo server to respond with a Prack depending upon whether or not Rel1XX
is in the required header of the 183 Session Progress.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Brian<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Ed Leatherman [mailto:ealeatherman@gmail.com]
<br>
<b>Sent:</b> Tuesday, October 15, 2013 9:49 AM<br>
<b>To:</b> Brian Meade (brmeade)<br>
<b>Cc:</b> Cisco VOIP<br>
<b>Subject:</b> Re: [cisco-voip] question(s) about SIP early media<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<p class="MsoNormal">Hi Brian,<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Here's what the signalling looks like, apologies for the formatting.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">No. Delta Time Source Destination Protocol Info<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 1 0.000000 0.000000 Vidyo Server CUCM SIP/SDP Request: INVITE
<a href="sip:83045551212@CUCM">sip:83045551212@CUCM</a> | , with session description<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 2 0.001193 0.001193 CUCM Vidyo Server SIP Status: 100 Trying | <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> RTP from MTP to Vidyo starts here <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 9 0.273383 0.274576 CUCM Vidyo Server SIP/SDP Status: 183 Session Progress | , with session description<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 47 0.751382 1.025958 CUCM Vidyo Server SIP Request: UPDATE
<a href="sip:Vidyo">sip:Vidyo</a> Server :50600;transport=UDP | <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 48 0.000829 1.026787 Vidyo Server CUCM SIP Status: 200 OK | <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 707 13.100773 14.127560 Vidyo Server CUCM SIP Request: CANCEL
<a href="sip:83045551212@CUCM">sip:83045551212@CUCM</a> :5060 | <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 708 0.000478 14.128038 CUCM Vidyo Server SIP Status: 200 OK | <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 710 0.004368 14.132406 CUCM Vidyo Server SIP Status: 487 Request Cancelled | <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> 711 0.000756 14.133162 Vidyo Server CUCM SIP Request: ACK
<a href="sip:83045551212@CUCM">sip:83045551212@CUCM</a> | <o:p></o:p></p>
</div>
</div>
</div>
<div>
<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
<div>
<p class="MsoNormal">On Tue, Oct 15, 2013 at 8:25 AM, Brian Meade (brmeade) <<a href="mailto:brmeade@cisco.com" target="_blank">brmeade@cisco.com</a>> wrote:<o:p></o:p></p>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Ed,</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">It will probably be much easier for use to follow the call flow if you could send the actual SIP
messaging for one of the calls.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Prack is really only used in response to a 180 Ringing with SDP or a 183 Session Progress with SDP.
That’s where early media gets established.</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Brian</span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> </span><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> cisco-voip [mailto:<a href="mailto:cisco-voip-bounces@puck.nether.net" target="_blank">cisco-voip-bounces@puck.nether.net</a>]
<b>On Behalf Of </b>Ed Leatherman<br>
<b>Sent:</b> Tuesday, October 15, 2013 8:19 AM<br>
<b>To:</b> Cisco VOIP<br>
<b>Subject:</b> [cisco-voip] question(s) about SIP early media</span><o:p></o:p></p>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I'm trying to troubleshoot what I think is an early media problem on a SIP trunk between CUCM 8.6 and a video conferencing system (Vidyo). If the Vidyo system tries to dial long
distance, it does not get the audio prompt for the authorization code, which comes in from our long distance carrier prior to the call being established.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Audio is OK for local calls once the call is established.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I don't have direct access to the vidyo side. so I took a few packet captures at the CUCM side to try and puzzle out what is going on.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Vidyo sends SDP info immediately in its Invite message, and CUCM begins to send back audio from the MTP right away. Does CUCM need to send a PRACK here, or is the Status 100 reply
from CUCM sufficient?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">CUCM also responds with it's own 183 session progress message back that includes it's own SDP info. I never see a PRACK back from Vidyo, nor do I get audio. Would this imply that
vidyo is not participating in the early media?<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">For a local call, vidyo does eventually start sending me audio when the session is completely established.<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On the CUCM side for the SIP trunk profile, I have Early Offer support for voice and video calls checked and SIP Rel1XX options set to send PRACK for all 1xx messages (tried both
settings though)<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I'm asking my internal customer that owns the vidyo system to contact vidyo tech support, but I figured I'd see if any of you SIP gurus had an opinion :)<o:p></o:p></p>
</div>
<div>
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
</div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">--
<br>
Ed Leatherman<o:p></o:p></p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<p class="MsoNormal"><br>
<br clear="all">
<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<p class="MsoNormal">-- <br>
Ed Leatherman<o:p></o:p></p>
</div>
</div>
</body>
</html>