RE: VPN Question

["David Gillett" <gillettdavid () fhda edu>]

  The usual issue is that the firewall the client is behind is
doing NAT (Network Address Translation) and the encapsulation
by the VPN software includes an encrypted copy of the client's
IP address.  At the VPN server (in your case, the SonicWall),
the "envelope" source IP address had been altered by the NAT,
and doesn't match what's inside the encrypted packet -- so the
server rejects it.

  Many VPN implementations include a "use UDP" mode that 
sidesteps this issue.  I don't see any mention of this on 
SonicWall's Pro230 site, though, so I suspect it might not.
(It might appear as a configuration option on the client
software....)

David Gillett


> -----Original Message-----
> From: Jim Brezicky [mailto:brezicky () infimed com]
>
>  Good afternoon all,  This posting is a little off track, but 
> I'm hoping someone can help me  anyway.  I have a SonicWall 
> Pro230 and I'm trying to do VPN with it. My users  connect 
> from some locations and not others. Example: They could 
> connect  from the Airport in Cincinnati, but not the airport 
> in Las Vegas. Seems  they can't connect in many (if any 
> hotels). In speaking with SonicWall  they said this is a 
> known issue when connecting through a firewall on the  hotel 
> side.  I know I'm not the first company to try this, and was 
> wondering how others  get by this issue? Or is this an 
> inherent SonicWall issue.  Most of my users are traveling 
> Sales people, and will go all around the  US, and Japan.  Any 
> insight would be GREATLY appreciated.  Thanks,  Jim Brezicky 
> InfiMed Inc 
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