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    <div class="moz-cite-prefix">Yes but I mean it in the context that
      you encapsulate the relevant 44 addresses at both sides.<br>
      (in the local lan addresses).<br>
      <br>
      <br>
      Bob VE3TOK<br>
      <br>
      On 13-11-17 12:08 AM, Michael E Fox - N6MEF wrote:<br>
    </div>
    <blockquote
      cite="mid:jb8eecikpfc6k6fsf64hoix6.1384664901886@email.android.com"
      type="cite">
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      <div>We are.  But the addresses don't matter since both ends are
        behind a firewall.  The addresses could be anything and the
        problem would be the same.</div>
      <div><br>
      </div>
      <div>Michael</div>
      <div>N6MEF</div>
      <div><br>
      </div>
      <div><br>
      </div>
      <div><br>
      </div>
      <div>
        <div style="font-size:9px;color:#575757">Sent from my Verizon
          Wireless 4G LTE smartphone</div>
      </div>
      <br>
      <br>
      -------- Original message --------<br>
      From: Bob Tenty <bobtenty@gmail.com> <br>
        Date:11/16/2013 8:44 PM (GMT-08:00) <br>
        To: <a class="moz-txt-link-abbreviated" href="mailto:nos-bbs@tapr.org">nos-bbs@tapr.org</a> <br>
        Subject: Re: [nos-bbs] UDP Port Unreachable - problem found <br>
        <br>
        <div class="moz-cite-prefix">I don't believe you mentioned about
          two jnos systems behind the same firewall but may be I missed
          it.<br>
          <br>
          Why are you not  using 44 addresses  in your axudp link  at
          both sides?<br>
          <br>
          Bob<br>
          <br>
          <br>
          On 13-11-16 09:20 PM, Michael E Fox - N6MEF wrote:<br>
        </div>
        <blockquote
          cite="mid:smwd0v826eqnmun4cut6ni60.1384653334317@email.android.com"
          type="cite">
          <meta http-equiv="Content-Type" content="text/html;
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          <div>No Bob, I'm talking about two JNOS systems behind the
            same firewall.   The firewall has to change the source port
            of at least the second one on the way out.  Otherwise, the
            destination IP and destination port are all the same on the
            way back in.  I believe I've already mentioned this a couple
            of times.  This is basic firewall connection muxing.</div>
          <div><br>
          </div>
          <div>Sonicwall happens to change the source port all the time,
            instead of after the first connection.  And it works just
            fine for everything but JNOS.  If JNOS behaved like a normal
            UDP app, it would work fine, too.</div>
          <div><br>
          </div>
          <div>The point is that there is simply no reason to require a
            specific source port.  It's just not the way the UDP world
            works.  And doing so renders the system unworkable when
            placed behind 10s of 1000s of commercial firewalls.</div>
          <div><br>
          </div>
          <div>The whole point of axudp is so it can be used in
            situations where axip can't be used.  But with this bizarre
            restriction, it's defeating that purpose.</div>
          <div><br>
          </div>
          <div>M</div>
          <div><br>
          </div>
          <div><br>
          </div>
          <div><br>
          </div>
          <div><br>
          </div>
          <div>
            <div style="font-size:9px;color:#575757">Sent from my
              Verizon Wireless 4G LTE smartphone</div>
          </div>
          <br>
          <br>
          -------- Original message --------<br>
          From: Bob Tenty <bobtenty@gmail.com> <br>
            Date:11/16/2013 3:38 PM (GMT-08:00) <br>
            To: TAPR xNOS Mailing List <nos-bbs@tapr.org> <br>
              Subject: Re: [nos-bbs] UDP Port Unreachable - problem
              found <br>
              <br>
              <div class="moz-cite-prefix">Michael,<br>
                <br>
                You are making a thinking error here.<br>
                <br>
                If I make a link to another jnos system the destination
                ip number is different.<br>
                Also the return route from that second jnos system uses
                another ip number as the first jnos system so there is
                no problem it all.<br>
                Even with the same port.  It is the combination of ip
                number + port.<br>
                <br>
                Those consumer router/firewall boxes are cheaply
                designed and targeted for the average Joe customer user
                needs.<br>
                Install dd-wrt in it if available for it and you will be
                much happier.<br>
                <br>
                <br>
                73,<br>
                <br>
                Bob VE3TOK<br>
                <br>
                <br>
                <br>
                <br>
                <br>
                <br>
                On 13-11-16 12:35 PM, Michael E. Fox - N6MEF wrote:<br>
              </div>
              <blockquote
                cite="mid:009701cee2f2$4ca88a80$e5f99f80$@mefox.org"
                type="cite">
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                  <p class="MsoNormal"><span style="color:#1F497D">Yes,
                      Linux leaves the source port alone on the first
                      connection.  But that only works for the first
                      JNOS system.  Even a firewall that initially leave
                      the source port alone will need to change the
                      source port if a second JNOS system exists so it
                      can track connections to two different machines.<o:p></o:p></span></p>
                  <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
                  <p class="MsoNormal"><span style="color:#1F497D">M<o:p></o:p></span></p>
                  <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
                  <div>
                    <div style="border:none;border-top:solid #B5C4DF
                      1.0pt;padding:3.0pt 0in 0in 0in">
                      <p class="MsoNormal" style="margin-left:.5in"><b><span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">From:</span></b><span
style="font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext">
                          <a moz-do-not-send="true"
                            class="moz-txt-link-abbreviated"
                            href="mailto:nos-bbs-bounces@tapr.org">nos-bbs-bounces@tapr.org</a>
                          [<a moz-do-not-send="true"
                            class="moz-txt-link-freetext"
                            href="mailto:nos-bbs-bounces@tapr.org">mailto:nos-bbs-bounces@tapr.org</a>]
                          <b>On Behalf Of </b>Bob Tenty<br>
                          <b>Sent:</b> Friday, November 15, 2013 11:37
                          PM<br>
                          <b>To:</b> TAPR xNOS Mailing List<br>
                          <b>Subject:</b> Re: [nos-bbs] UDP Port
                          Unreachable - problem found<o:p></o:p></span></p>
                    </div>
                  </div>
                  <p class="MsoNormal" style="margin-left:.5in"><o:p> </o:p></p>
                  <div>
                    <p class="MsoNormal" style="margin-left:.5in">Yes, I
                      have seen that with those boxes.  That is why I
                      always replace the firmware with linux when
                      possible.<br>
                      <br>
                      Bob<br>
                      <br>
                      <br>
                      On 13-11-16 01:33 AM, Michael E. Fox - N6MEF
                      wrote:<o:p></o:p></p>
                  </div>
                  <blockquote
                    style="margin-top:5.0pt;margin-bottom:5.0pt">
                    <p class="MsoNormal" style="margin-left:.5in">I
                      found the problem with the UDP port 93 unreachable
                      message:  JNOS is (incorrectly) requiring the
                      source port to also be 93 in AXUDP connections.<o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in"> <o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in">When I
                      connect outbound from my JNOS system, through my
                      firewall, the firewall is changing the source port
                      when it performs the outbound NAT.  But this is
                      normal for a firewall.  In fact, it HAS to do this
                      if it’s going to allow for multiple connects of
                      the same protocol from different machines.  Many
                      consumer-grade firewalls will leave the source
                      port alone for the first connection (if it’s not
                      already in use) and only change it for subsequent
                      connections.  SonicWall is a bit more strict,
                      frequently changing the source port, making it
                      harder for intercepted packets to be tracked to
                      any one machine.<o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in"> <o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in">Normally,

                      this doesn’t matter.  Applications/services listen
                      on a particular port and respond to whatever
                      incoming connections use that *<b>destination</b>*
                      port.  They don’t care what the source port is. 
                      Firewalls then use different source ports to track
                      multiple conversations so that when the packets
                      return, all addressed to the same external NAT
                      address, it can direct them to the proper place by
                      the port number.<o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in"> <o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in">But
                      when JNOS receives an AXUDP packet, apparently it
                      doesn’t behave like a normal UDP application. 
                      JNOS apparently rejects the connection if the *<b>source</b>*
                      port is not 93, even if the destination port is
                      correctly set to 93.  This is unusual, to say the
                      least.  But even worse, it issues an ICMP “udp
                      port 93 unreachable” message which is completely
                      wrong, since port 93 is definitely reachable.<o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in"> <o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in">It
                      seems the following is needed:  Remove the source
                      port restriction for AXUDP.  JNOS should not care
                      what the source port is.  And, just like any other
                      UDP app, when responding it should use whatever
                      source port was specified as the destination port
                      when it constructs the return packet.<o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in"> <o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in">Michael<o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in">N6MEF<o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in"> <o:p></o:p></p>
                    <p class="MsoNormal" style="margin-left:.5in"><span
                        style="font-size:12.0pt;font-family:"Times
                        New Roman","serif""><br>
                        <br>
                        <br>
                        <o:p></o:p></span></p>
                    <pre style="margin-left:.5in">_______________________________________________<o:p></o:p></pre>
                    <pre style="margin-left:.5in">nos-bbs mailing list<o:p></o:p></pre>
                    <pre style="margin-left:.5in"><a moz-do-not-send="true" href="mailto:nos-bbs@tapr.org">nos-bbs@tapr.org</a><o:p></o:p></pre>
                    <pre style="margin-left:.5in"><a moz-do-not-send="true" href="http://www.tapr.org/mailman/listinfo/nos-bbs">http://www.tapr.org/mailman/listinfo/nos-bbs</a><o:p></o:p></pre>
                  </blockquote>
                  <p class="MsoNormal" style="margin-left:.5in"><span
                      style="font-size:12.0pt;font-family:"Times
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                <pre wrap="">_______________________________________________
nos-bbs mailing list
<a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:nos-bbs@tapr.org">nos-bbs@tapr.org</a>
<a moz-do-not-send="true" class="moz-txt-link-freetext" href="http://www.tapr.org/mailman/listinfo/nos-bbs">http://www.tapr.org/mailman/listinfo/nos-bbs</a>
</pre>
              </blockquote>
              <br>
            </nos-bbs@tapr.org></bobtenty@gmail.com></blockquote>
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