We have a foreign delegation coming in next week. Some of them will be IT-savvy. We don't want them wandering through our network. We have a wired network and a wireless network both going through the one ADSL router.
Can I set up the wireless user to be on a separate network? Is it still possible for the wired and wireless groups to connect to the internet?
I use my WRT54G with DD-WRT firmware to achieve this - you are able to create multiple 'virtual' interfaces with different subnets and rules; thus separating the networks and ensuring that traffic does not leak over to the other.
If all you want to do is give them access to the internet and you aren't too many of them, the easiest solution is to buy a consumer-grade DSL router and plug it into the DMZ or outside the firewall.