While the Windows Firewall included in the newest client OS, Windows 7 (download) is more evolutionary than revolutionary, it does provide some nice tweaks to make it more user-friendly and at least one big change that makes a difference to mobile users. To access, just click the Advanced Settings link in the Control Panel, you’ll find three choices to choose  from: public network, home network or work network. If you select "home network", you can set up a Homegroup, network discovery is automatically turned on so you will be able to see the other computers and devices on the network and they will be able to see your computer.

Full Article: WindowsSecurity