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<p class=MsoPlainText>G'day Todd and Jimmy<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Some other things to consider, which might help is:<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:
l0 level1 lfo1'><![if !supportLists]><span style='font-family:Symbol'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>(Disclaimer, I am not 100% sure if I am correct
here [or my terminology], but I have seen instances that leads me to believe
this is the case.) RAT uses the same port for both sending and receiving audio.
Therefore, if you are using a "stateful" firewall (ie, allows traffic
in on the same port as going out), then this might explain why Rat works. Whereas,
in simple terms, vic uses to different ports for incoming and outgoing traffic.
This is why, if using a stateful firewall, vic doesn’t work correctly!<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText style='margin-left:36.0pt;text-indent:-18.0pt;mso-list:
l0 level1 lfo1'><![if !supportLists]><span style='font-family:Symbol'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>The other thing that I have seen with “some”
NAT’ed networks is:<o:p></o:p></p>
<p class=MsoListParagraph><o:p> </o:p></p>
<p class=MsoPlainText style='margin-left:72.0pt;text-indent:-18.0pt;mso-list:
l0 level2 lfo1'><![if !supportLists]><span style='font-family:"Courier New"'><span
style='mso-list:Ignore'>o<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>Traffic would only be received, if you are
transmitting. IE, no-one in rat would appear unless the talk button is enabled.
This also occurred in vic as well.<o:p></o:p></p>
<p class=MsoPlainText style='margin-left:72.0pt'><o:p> </o:p></p>
<p class=MsoPlainText style='margin-left:72.0pt;text-indent:-18.0pt;mso-list:
l0 level2 lfo1'><![if !supportLists]><span style='font-family:"Courier New"'><span
style='mso-list:Ignore'>o<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>Because of a “Nat’ed” network,
each AG would appear as the same single ipaddress connecting to a Bridge. Because
of the way unicast works (ie, only one ipaddress/port can connect at a single
time), only a single AG site can connect to each bridge to work properly.
Therefore, have you tried connecting using separate bridges?<o:p></o:p></p>
<p class=MsoPlainText style='margin-left:108.0pt;text-indent:-18.0pt;
mso-list:l0 level3 lfo1'><![if !supportLists]><span style='font-family:Wingdings'><span
style='mso-list:Ignore'>§<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>I
have seen this issue at a particular site, where if person A connects to Bridge
X, person B can connect to Bridge X, but the traffic isn’t being sent or received
correctly.<o:p></o:p></p>
<p class=MsoPlainText style='margin-left:108.0pt'><o:p> </o:p></p>
<p class=MsoPlainText>I hope some of this makes sense and helps.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Cheers,<o:p></o:p></p>
<p class=MsoPlainText>Jason.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText><span lang=EN-US>-----Original Message-----<br>
From: Todd Zimmerman [mailto:todd.zimmerman@ubc.ca] <br>
Sent: Saturday, 1 November 2008 04:25 AM<br>
To: Jimmy Miklavcic<br>
Cc: ag-tech@mcs.anl.gov<br>
Subject: Re: [AG-TECH] AG and NAT'ed networks.</span></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>On Tue, 2008-10-28 at 11:12 -0600, Jimmy Miklavcic wrote:<o:p></o:p></p>
<p class=MsoPlainText>> I'm working with Kansas University Medical Center
and we've been<o:p></o:p></p>
<p class=MsoPlainText>> having troubles connecting via AG. They have a
NAT'ed network and we<o:p></o:p></p>
<p class=MsoPlainText>> are using unicast. We connect and communicate via
RAT but we are<o:p></o:p></p>
<p class=MsoPlainText>> unable to exchange video. The strange thing is that
I a seeing their<o:p></o:p></p>
<p class=MsoPlainText>> private IP address in the RAT, I assume that I
should be seeing a more<o:p></o:p></p>
<p class=MsoPlainText>> public address.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Not necessarily. When you say "in the RAT" I
assume you mean listed on<o:p></o:p></p>
<p class=MsoPlainText>the RAT gui?? This ip comes from the RTCP and RAT
settings and does not<o:p></o:p></p>
<p class=MsoPlainText>necessarily reflect what is actually happen at the
network level.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>To see where the packets are actually being sent would
probably require<o:p></o:p></p>
<p class=MsoPlainText>a tcpdump. <o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText> <o:p></o:p></p>
<p class=MsoPlainText>> I'm trying to understand the bridges' process flow.
If two sites are<o:p></o:p></p>
<p class=MsoPlainText>> connected to a bridge via unicast, does the
unicast/multicast bridge<o:p></o:p></p>
<p class=MsoPlainText>> process convert my unicast traffic to multicast then
back to unicast<o:p></o:p></p>
<p class=MsoPlainText>> before sending the stream to the other site? If that
is the case then<o:p></o:p></p>
<p class=MsoPlainText>> I can understand why we can't exchange video.
Multicast can't handle<o:p></o:p></p>
<p class=MsoPlainText>> private IP space. But then, why does RAT work?<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>If two sites are connected to the same bridge, then I
don't think there<o:p></o:p></p>
<p class=MsoPlainText>is a double conversion. I can't guarantee that, but it
wouldn't really<o:p></o:p></p>
<p class=MsoPlainText>make sense. I assume incoming unicast is redistributed
to all existing<o:p></o:p></p>
<p class=MsoPlainText>unicast connections - then sent to the multicast address
as required.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>My guess is that your suspicion of the bridge is not
where the problem<o:p></o:p></p>
<p class=MsoPlainText>lies - my guess it is the NAT'ing and/or firewall.
Correct me if I'm<o:p></o:p></p>
<p class=MsoPlainText>wrong experts!! but I believe for NAT'd networks, you
have to port<o:p></o:p></p>
<p class=MsoPlainText>forward the required AG ports (video anyway) to the
designated internal<o:p></o:p></p>
<p class=MsoPlainText>computer.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Cheers,<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Todd<o:p></o:p></p>
<p class=MsoPlainText> <o:p></o:p></p>
<p class=MsoPlainText>-- <o:p></o:p></p>
<p class=MsoPlainText>Collaboration & Visualization Specialist<o:p></o:p></p>
<p class=MsoPlainText>UBC Okanagan - http://web.ubc.ca/okanagan<o:p></o:p></p>
<p class=MsoPlainText>WestGrid - www.westgrid.ca<o:p></o:p></p>
<p class=MsoPlainText>Ph. 250-807-9979<o:p></o:p></p>
<p class=MsoPlainText>Todd Zimmerman - todd.zimmerman@ubc.ca<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
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