What is the best solution to enable two or more completely separate internal networks, to securely share the same ADSL based broadband connection?
For example, often it is desirable for there to be one high specification broadband connection installed into a large building, but where the individual departments or users within that building, need to then be on completely separate internal networks. Each separate department or user therefore would need to be able to access the Internet and possibly their own system remotely, without there being a security risk posed by the computers effectively being linked ( albeit loosely ) together.
The users in this scenario would either have simple Windows peer to peer, or Windows server based, networks.
What would therefore be the most viable way forward, without purchasing a prohibitively expensive IT solution.