Topic: a network if with two IP addresses?

someone showed me this wifi liberator program and it seemed like overkill to me needing two wifi cards (internal and USB) and having to install the software on all computers (access point and clients).  the purpose of the software is to have one person pay for access to a wireless network somewhere like an airport and then be able to act as a free AP for anyone else wishing to access the Internet.

anyways, this got me thinking and I was wondering if you could do this without two wifi cards.  but then the one wifi card would have to have two IP addresses since you'd have to do NAT between the paid wifi network and the free one you're providing.

is this possible in any of the BSDs?  is it even possible theoretically for a network if to have two IPs?

Re: a network if with two IP addresses?

http://en.wikipedia.org/wiki/IP_aliasing and ifconfig(8) - look for the 'alias' keyword.  I hope that's what you're looking for.

Keep Smiling

Re: a network if with two IP addresses?

I don't think it's possible: For your wifi card to connect to the AP, it needs to be in managed mode. For other wifi cards to be able to connect to your wifi card, your wifi card needs to be in ad-hoc mode. With all wifi cards that I've seen so far, this is an either-or.

Re: a network if with two IP addresses?

thanks, guys.