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New Member

VPN 3.5.1C Thru a small router wth NAT to a PIX


I'm trying to configure a VPN client (3.5.1C) for a remote office that uses a Netgear RM356 router. This router conencts to a dialup Internet service and serves a small network for 4 users and uses NAT.

The problem is that the VPN client cannot seem to authenticate - it transmits to the PIX but does not receive back a response during the handshake process.

The PC can connect to the PIX when dialed driectly into the ISP.

Can anyone suggest what needs to be set on the Router/PIX/Client to get this to work or maybe suggest a better solution for a small remote office?

Cisco Employee

Re: VPN 3.5.1C Thru a small router wth NAT to a PIX

Just want to clarify, are you using the PIX to terminate the VPN connection? The PIX currently doesn't support IPSec thru NAT or IPSec thru TCP, which is the one you would need to turn on the client and vpn head end.

If you terminate your VPN on say a VPN 3000,

this device supports ipsec over udp or ipsec thru tcp and you would be able to operate the client behind a NAT/PAT device, see:

New Member

Re: VPN 3.5.1C Thru a small router wth NAT to a PIX

Yes, we are using a PIX to terminate the VPN. That explains why we cannot use the 3.5.1C client through this router.