Windows IP Forewarding

WIPFW is a MS Windows
operable version of IPFW for FreeBSD OS. You can use the
same functionality and configure it as only you work with IPFW.
IPFW is a packet filtering and accounting system which resides in
the kernelmode, and has a user-land control utility, ipfw. Together,
they allow you to define and query the rules used by the kernel in
its routing decisions.
There are two related parts to ipfw. The firewall section
performs packet filtering. There is also an IP accounting section
which tracks usage of the router, based on rules similar to those
used in the firewall section. This allows the administrator to
monitor how much traffic the router is getting from a certain
machine, or how much WWW traffic it is forwarding, for example.
As a result of the way that ipfw is designed, you can use ipfw on
non-router machines to perform packet filtering on incoming and
outgoing connections. This is a special case of the more general use
of ipfw, and the same commands and techniques should be used in this
situation.