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New Member

ISP's restrictions on VPN traffic !!

Hi all,

A general question.

How do I find out if an ISP lets me pass VPN traffic in thair network? I hear most Cable \ DSL providers block Ipsec traffic. Is thare a way of finding out.

I have a PIX 520 that I want to be reached by an CPN client. It works when I try to reach it throuh a dial up line. But not through my DSL modem!

How do I check this?



VIP Purple

Re: ISP's restrictions on VPN traffic !!

It is difficult to get IPSec working through PAT (so difficult, don't even try).

You may find that your cable modem is doing PAT, while your dial up connection is not.

New Member

Re: ISP's restrictions on VPN traffic !!

That is correct. PIX does not support PAT Port Address Translation from the client side. Your Dialin ISP is using either straight IP's or NAT and you cable modem is doing PAT.

I beleive the only VPN device in the world that will support this is the Cisco VPN Concentrator like the 3005 etc. That is one of Cisco's selling points.