>    I'm trying to configure a NetBSD box to do PPP dialup and IP
>    Masquerading.
>    [stuff deleted]
>    # Assume IP given is 128.175.143.20
>    map ppp0 192.1.1.0/24 -> 128.175.143.20/32 portmap tcp/udp 2000:40000
>    map ppp0 192.1.1.0/24 -> 128.175.143.20/32
>
>    Or something completly different?

There is a step by step guide to setting this up at
http://radon.moof.ai.mit.edu/~armenb/ipnat.html that might help.

Mike.