There is a service supporting this feature. Its name is Wired AutoConfig. By default, in Windows 7 this service is disabled.
In order to have the tab appearing again in your LAN properties, just in case you need to test something or you plan to add improved security to your network probably by using a RADIUS server you will have to start this service.
To do that, navigate to Start – Run – type in “services.msc” without the quotes and hit enter. Locate “Wired AutoConfig” service, double click it and you should change the startup type to “automatically” and use start to manually start it.