This article lets users enable/disable a tag from command line in a few easy steps.
The document shows how to carry out this activity on Windows XP by installing DevCon. The link to download this is provided in the article. This software displays all devices and thus the user can enable or disable a device according to his requirement. The commands for doing this are included in the article.
This allows you enable/disable your internet connection (or network card) on the command line.