A blog by Devendra Tewari
Normally, commercial operating systems do not act as routers. They discard any IP packet with a destination IP address not assigned to an active network interface. It is fairly easy to enable IP forwarding, there are instructions elsewhere to do so on Windows and Linux.
You’ll also need to add appropriate route settings to the routing table, so that the IP packets are routed through the correct network interface. This can be done using the route add command on Windows and Linux.
I have had problems routing multicast packets (IP addresses 224.0.0.0 through 239.255.255.255, formerly referred to as Class D addresses). Windows does not route multicast traffic by default. Using EnableMulticastForwarding does not automatically enable it either.