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<div class="moz-cite-prefix">Hello,<br>
<br>
Look on Wikipedia and read the articles for SIP, RTP, NAT and
STUN.<br>
<br>
The answer to your question can be found in the above articles.<br>
<br>
David<br>
<br>
On 13-02-27 10:26 PM, Khoa Pham wrote:<br>
</div>
<blockquote
cite="mid:CAN+NExE7LouEOaYfbg14+1w+wMqEmKTx9Z8Pk4nf=U=V_EzdSA@mail.gmail.com"
type="cite">
<div dir="ltr"><span
style="font-family:arial,sans-serif;font-size:13px">Hi, I have
Kamailio as SIP server and RTP server. Client is PJSIP.</span>
<div style="font-family:arial,sans-serif;font-size:13px"><br>
</div>
<div style="font-family:arial,sans-serif;font-size:13px">
I read that STUN is for non-symmetric NAT, and RTP server is
for symmetric NAT. </div>
<div style="font-family:arial,sans-serif;font-size:13px"><br>
</div>
<div style="font-family:arial,sans-serif;font-size:13px">Supposed
A calls B.</div>
<div style="font-family:arial,sans-serif;font-size:13px"><br>
</div>
<div style="font-family:arial,sans-serif;font-size:13px">If A, B
both use symmetric NAT and STUN, they cannot hear each other</div>
<div style="font-family:arial,sans-serif;font-size:13px">
If A or B use non-symmetric NAT and NOT using STUN, they
cannot hear each other.</div>
<div style="font-family:arial,sans-serif;font-size:13px"><br>
</div>
<div style="font-family:arial,sans-serif;font-size:13px">Why is
that?</div>
<div style="font-family:arial,sans-serif;font-size:13px"><br>
</div>
<div style="font-family:arial,sans-serif;font-size:13px">I read <a
moz-do-not-send="true"
href="http://tools.ietf.org/id/draft-takeda-symmetric-nat-traversal-00.txt"
target="_blank">http://tools.ietf.org/id/draft-takeda-symmetric-nat-traversal-00.txt</a> for <span
style="white-space:pre-wrap">Prediction Failure, is that
related to this problem ?</span></div>
<div><br>
</div>
-- <br>
<span style="color:rgb(0,0,0)">Khoa Pham</span><br
style="color:rgb(0,0,0)">
<span style="color:rgb(0,0,0)">HCMC University of Science</span><br
style="color:rgb(0,0,0)">
<span style="color:rgb(0,0,0)">Faculty of Information Technology</span><br>
</div>
<br>
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<br>
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</pre>
</blockquote>
<br>
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