Is it possible to set up your computer as a lan network?

[Richard]

Any wireless router should be able to provide a WiFi network. This applies independently of whether the router is connected to the Internet or is free standing without any WAN connection. Some routers have the option to block working between different wireless clients. If your router has this option, make sure it is disabled.

It is always worth trying setting the router on different channels to see if you are experiencing interference from other nearby networks.

To answer your question, some of the latest versions of Windows will provide a virtual router capability. However, all versions of Windows (from XP onwards) should offer a facility called Internet Connection Sharing (ICS). To use ICS to provide the WiFi network you require, then the computer must have at least two network adapters. One must be the wireless adapter you want to use, the other typically will be an Ethernet adapter. Open the properties for this second (possibly Ethernet) adapter from Network & Sharing Center. In one of the tabs of the properties window, you should find the option to share this computer's Internet connection. Set this option and reboot the computer. You will need to set up the wireless network, which may have to be an Ad-hoc network. The computer will provide DHCP facilities for other computers.

A further approach could be simply to set up all the gaming computers in an Ad-hoc network without having one of the computers providing DHCP facilities. In this case, the various computers will have to be configured with static addresses, which must all be in the same sub-net, but each must be unique.

Finally, be aware that some tablet devices do not recognise Ad-hoc networks, and you have to rely on an Infrastructure network as is typically provided by a router.

I hope this helps.