How do I block a range of I.P. addresses using whatever techniques available using any software that currently exists and/or a wireless router that's already configured and functioning correctly the way I want it. I want to block packets(all connection) from the I.P. range in usage with hosting an online game to keep cheaters out and I'm not sure where to start. I'm also trying to get through to my router manufacturer's technical support but they are very busy and I must try back during the wee hours when I want to get through to a technician so I'm posting here.

The question is, how would you figure out, what ip-range has to be blocked? Most IPs are assigned dynamically.

I don't have the ranges yet but would like to know how to block ranges. There's a third party program I can find out what I.P. their using and they can keep changing the last digits of their I.P. so I need to block the range so no packets can get through so they can't connect. I have thought of upgrading my router's firmware to DD-WRT but I feel that it's too complicated of an installation technique in order to perform it myself, so I will call the computer store and ask them if they can do it, because I don't want to brick my router, and I also wonder whether there is another way out there.