ProtBlock is a special Windows based controller/firewall tool, with its help you can remotely manage/control the computers in an internal/extarnal network.
Just install the two parts of the package to the computers and you are able to do the following things even in a workstation:
you can control the remote computers via net (lan, internet)
you can send messages
you can enable/disable the network usage
you can ban IP addresses determining prohibited web/irc/chat/p2p sites
you can trust IP addresses determining visitable websites for children limiting the usable network (for instance only the local network)
you can shut down/restart/log off the computers
you can copy files
you can get the screenshot of the remote computers (screen Thief)
you can update itself (the service program on clients too)
you can do all via secure connection Between computers