As an administrator of the contoso corporation, you are responsible for configuring the users' mobile computers. you want to ensure that when a computer system accesses a public network—such as the local coffee shop, the airport, or the user's home network—other computers and devices cannot find your system. in addition, you want to disable file and printer sharing access. however, when in the office and the computers connect to the office using a vpn client, you want network discovery and file and printer sharing available. what should you do?