<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
On 2/08/2011 1:02 AM, Robert Huddleston wrote:
<blockquote cite="mid:04d301cc506c$bca45c80$35ed1580$@com"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
charset=ISO-8859-1">
<meta name="Generator" content="Microsoft Word 12 (filtered
medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-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;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;}
@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]-->
<div class="WordSection1">
<p class="MsoNormal">Anyone have any testing experience with T38
and HT-502 Grandstream?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I just want to confirm that t.38 is working
on this device.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p><br>
</p>
</div>
</blockquote>
<br>
Yes, it works.<br>
<br>
I currently have latest firmware installed and it still works in
T.38. I am using UDP transport for this device as I seem to
encounter problems with TCP or TLS.<br>
<br>
I am currently running Asterisk 1.8.5.0.<br>
<br>
<table border="0" cellpadding="2" cellspacing="1" width="100%">
<tbody>
<tr>
<td align="right"><b>Product Model: </b></td>
<td> HT-502 V1.1C </td>
</tr>
<tr>
<td align="right"><b>Software Version: </b></td>
<td> Program-- 1.0.5.5 Bootloader-- 1.0.0.9 Core--
1.0.5.2 Base-- 1.0.5.2</td>
</tr>
</tbody>
</table>
<br>
Some settings I have set and you may wish to check for the FXS port
are;<br>
<br>
<table border="0" cellpadding="2" cellspacing="1" width="100%">
<tbody>
<tr>
<td align="right"><i>Force INVITE: </i></td>
<td> <input value="0" checked="checked" name="P265"
type="radio"> No <input value="1" name="P265"
type="radio"> Yes (Always refresh with INVITE instead of
UPDATE)</td>
</tr>
<tr>
<td align="right"><i>Send Re-INVITE After Fax: </i></td>
<td> <input value="0" name="P4367" type="radio"> No <input
value="1" checked="checked" name="P4367" type="radio"> Yes
</td>
</tr>
</tbody>
</table>
<br>
<table border="0" cellpadding="2" cellspacing="1" width="100%">
<tbody>
<tr>
<td align="right"><i>VAD: </i></td>
<td> <input value="0" name="P50" type="radio"> No <input
value="1" checked="checked" name="P50" type="radio"> Yes </td>
</tr>
<tr>
<td align="right"><i>Symmetric RTP: </i></td>
<td> <input value="0" checked="checked" name="P291"
type="radio"> No <input value="1" name="P291"
type="radio"> Yes </td>
</tr>
<tr>
<td align="right" valign="top"><i>Fax mode: </i></td>
<td> <input value="0" checked="checked" name="P228"
type="radio"> T.38 (Auto Detect) <input value="1"
name="P228" type="radio"> Pass-Through </td>
</tr>
<tr>
<td align="right"><i>Fax tone detection mode: </i></td>
<td> <input value="1" name="P894" type="radio"> Caller <input
value="0" checked="checked" name="P894" type="radio">
Callee <input value="2" name="P894" type="radio"> Caller
or Callee</td>
</tr>
<tr>
<td align="right" valign="top"><i>Jitter buffer type: </i></td>
<td> <input value="0" checked="checked" name="P133"
type="radio"> Fixed <input value="1" name="P133"
type="radio"> Adaptive </td>
</tr>
<tr>
<td align="right" valign="top"><i>Jitter buffer length: </i></td>
<td> <input value="0" checked="checked" name="P132"
type="radio"> Low <input value="1" name="P132"
type="radio"> Medium <input value="2" name="P132"
type="radio"> High </td>
</tr>
</tbody>
</table>
<br>
<br>
You will need to ensure you are using redundancy mode instead of
FEC.<br>
<br>
I am able to send a fax via my voice provider seemingly without
errors even though ECM is not enabled, this is because redundancy
mode is working as expected on the outbound communication.<br>
<br>
Unfortunately my voice provider only sends one data item in the
incoming UDPTL hence the occasional missed line.<br>
<br>
Here is an extract from my sip.conf<br>
<br>
[general]<br>
.<br>
.<br>
t38pt_udptl=yes,redundancy,maxdatagram=400<br>
.<br>
.<br>
[906]<br>
; Grandstream HT502 FXS Port<br>
; Analogue FAX Modem attached<br>
type=friend<br>
defaultuser=906<br>
md5secret=c5bca943c9b0cc303c496fbf9d48a48e<br>
call-limit=1<br>
disallow=g722<br>
transport=udp<br>
qualify=yes<br>
directmedia=no<br>
host=dynamic<br>
context=FAX-T38<br>
faxdetect=no<br>
deny=0.0.0.0/0.0.0.0<br>
permit=10.0.0.0/255.0.0.0<br>
permit=172.16.0.0/255.240.0.0<br>
permit=192.168.0.0/255.255.0.0<br>
<br>
Larry.<br>
</body>
</html>