Isolate infected system from network

[kraal]

I am using four computers going through a Linksys WRT54GS router. One of them recently got a virus. So I want to isolate that system from the network so that it can't spread viruses etc through the network.

Now what I want to ask is that how can I isolate that system?

[Howitzer]

Your might be running an anti virus program on your systems. Scan your infected system and remove the virus completely. Also your router might be having some security features and built in firewall, so use them to protect other systems within the network. You may also use some software firewalls to protect your system.

[Lemog]

Various ways to isolate computers:

1. Using Firewall
   Using Firewall is the easiest and simplest way to isolate a computer. It can be used in two ways by port (hardware) and by application (software) and provides the flexibility for incoming as well as outgoing traffic.
   
2. Using "Clean room" isolation
   A "clean room" computer is a machine without any network connectivity most likely hidden from Internet. The types of circumstances that require this degree of isolation are vanishingly few, but they do exist.