The question re: IPsec for traffic on the same port in my mind depends on
how you have implemented your policies.

Do you have IPsec active based on Windows policies and if so are you using
tunnel or transport mode policies?
Also what is the scenario for the port use? Is it generated by a second
session initiated from a client that has already connected and established
an escapsulated session or is the traffic from a different client?

Re: IPsec over NAT. Yes, as long as ESP is the protocol used to escapsulate
the traffic in Quick Mode. AH does not support NAT Traversal. In Windows
you have to enable the functionality through a reg key though:
http://support.microsoft.com/kb/885407/en-us

Jason



wrote in message
news:1175439542.212360.144500@y66g2000hsf.googlegr oups.com...
> In my environment there is IPSec already installed . I want to install
> another layer of IPSec on the some particular port .As i don't want to
> existing IPSec policies , is it possible to have encryption twice on
> the same port.
>
>
> Even if some programming is required for the same it is perfectly fine
> for us.
>
> Please let me know multiple chaining of encryption is support in
> windows XP or not.
>
>
> I have one more question. Does IPSec works with NAT.
>
> Thanks
>