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<DIV><FONT face=Arial size=2><SPAN class=656214310-24052006>Hi
All,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=656214310-24052006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=656214310-24052006>I notice during the
NGREP session , there is this field called Call-ID . It is something like this
format :-</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><A
href="mailto:9ce97fd3-1a800040@172.16.1.123">9ce97fd3-1a800040@172.16.1.1<SPAN
class=656214310-24052006>23</A></SPAN>.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial size=2>According to the RFC
, it is said that this field is generated by the UA who started the request. I
was just wondering, how did they get the IP Address at the back ? Which IP
Address did they reference it from ?</FONT></SPAN></DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial size=2>From the RFC, it
also says that the all request/response in the dialog should use the same
Call-ID. When they say this, does it mean the entire field with the ip
address (eg. <A
href="mailto:9ce97fd3-1a800040@172.16.1.123">9ce97fd3-1a800040@172.16.1.123</A>
) or just the front part of it (eg. 9ce97fd3-1a800040 ) ?</FONT></SPAN></DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial size=2>I notice that during
a dialog session from a UA to the server going to the PSTN gateway, it was
refering to this Call-ID until the point when the request was forwarded to the
PSTN gateway. When the PSTN gateway replies, it replied with a same Call-ID with
a different IP address at the back (<A
href="mailto:9ce97fd3-1a800040@123.234.123.234">9ce97fd3-1a800040@123.234.123.234</A>
)</FONT></SPAN></DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial size=2>172.16.1.123 -
Private address of the UA</FONT></SPAN></DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial size=2>123.234.123.234 -
Public address of the UA</FONT></SPAN></DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial size=2>Strange ? Give your
comment. Somehow i feel that this implementation is wrong.</FONT></SPAN></DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=656214310-24052006><FONT face=Arial
size=2>Regards,<BR>Sam</FONT></SPAN></DIV></BODY></HTML>