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<p class=MsoNormal>Hello all,<o:p></o:p></p>
<p class=MsoNormal> We recently retired a procedure that has been
in place for some time that will finally allow me to move our VPN to
L2TP/IPsec. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>My Windows 2003 VPN server is behind our firewall and uses
NAT. <o:p></o:p></p>
<p class=MsoNormal>All our VPN users are behind a home NAT firewall or the
likes most of the time.<o:p></o:p></p>
<p class=MsoNormal>Enter NAT-T. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Long story short I have successfully configured my VN
connection from home using L2TP/IPsec with NAT-T. I have 2 other users that
have assisted me in testing the connection. They have had 0 issues so far. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Microsoft has not supported NAT-T since XP SP2 and they
claim this configuration could “behave unexpectedly”. However all I
have been able to find in my research is some people get it to work and others can’t
seem to even after the needed registry edits. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>So other than “unexpectedly” meaning “it
should have worked but didn’t” has anyone else use a Windows based L2TP/IPsec
VPN server behind a NAT firewall as well their remote clients using NAT and
seen odd behavior? Anyone using a similar configuration with no trouble at all?
<o:p></o:p></p>
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