Creating an Access Point in Windows 7
In Windows 7 it’s possible to create an Access Point without any additional hardware.
First you have to start a command prompt as administrator. Do this by typing “cmd” in the start menu search box. Then right click on “cmd.exe” and choose “Run as administrator”.
Then enter the command
netsh wlan set hostednetwork mode=allow “ssid=CustomSSID” key=CustomKey keyUsage=persistent
Change “CustomSSID” with the name of the Access Point you would like to create. “CustomKey” should be changed to the security key you want to use (this must be entered by the clients).
Starting and stopping the network is done by typing:
netsh wlan start hostednetwork
netsh wlan stop hostednetwork
The advantage of creating an Access Point instead of an Ad-Hoc network is that multiple clients are able to connect, and that Windows 7 acts as a DHCP server (so no need to set up ip adresses yourself). It is also possible to connect to a Wireless network, while having the virtual Access Point running
The disadvantage is that you have to start and stop the Access Point from an elevated command prompt.
If you want to be able to share your internet connection, I would take a look at Connectify, this is also possible from within Windows 7, but Connectify makes the process a whole lot easier.