How do you block ip address?

How to block particular IP address in Internal network to access internet?

• We found that one computer with particular IP address consuming almost all network bandwidth of our organisation. How can I block that computer to access internet? Below are some configuration of network - We have domain based infrastructure with no IP Security policy. - Automatic IP address configured through DHCP. - No IP security policy - No ISA configured. - We are using Cisco network devices - Normal settings for DNS,DHCP and DC configured. Now, how can I prevent that computer to consume network bandwidth without going to the computer? NOTE:We are able to get that computer's IP address through network monitoring software. And found that the computer accessing internet through different ports.

• Answer:

  I agree with the other answers about MAC address filtering. But why no security policy? And why don't you want to track down the PC that's eating up all the bandwidth? Is that some kind of passive aggressive problem solving method? That PC might have a virus causing it to spew a bunch of garbage data. You would be doing everyone a favor by tracking down the offending computer as soon as possible.