Internet only within a LAN

[dandy34]

I support a public library along with several other sites and recently had to make a change on the network that exposed patron computers to the LAN. I would like to set them up so that they login the local machine only and can only see the internet, not browse my network.
I thought about configuring a swtich as a "192" net and placing that between the patron machines and the library switch. So far this hasn't worked too well.
Has anyone ever dealt with this?
Thanks

 

[avilov]

you can create a new VLAN for that computer and limit access to/from that VLAN on your router.