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Can't get VPN Client to work over ISDN

I am using VPN client version 3.6.2a on my laptop and cannot connect to our PIX 501 at work. If I do a modem dial up to my ISP, I have no problem connecting at all. However when I connect from home over my ISDN line the client shows connected but is only encrypting outgoing traffic with no external traffic coming in and being decrypted. I am using a Cisco 802 isdn router at home. I don't have overlapping networks. I am using NAT at home and at work.

Any suggestions?

Cisco Employee

Re: Can't get VPN Client to work over ISDN


If you are able to connect using a dial up, then your client and Pix configs are good.

If you are not able to make a connection through your ISDN link, then it is your PAT that is the issue. As of today, IPSec Through NAT option is not supported on the pix and will be supported in Pix Version 6.3(Ipsec Over UDP).

You will be able to make a connection through PAT because phase 1 uses UDP Port 500 but when it comes to encrypting traffic, ESP is a protocol and does not support PAT.