Hi Charles,

As Jagdeep stated port security is going to be a tough task and not a very feasible solution when you have multiple users in your network.

I can think of 2 possible solutions out of which Jagdeep already mentioned dot1x which is identity based networking or VMPS where you have pre approved mac address listed in a text file with vlan number they should be assigned dynamically and is any machine gets into the network whose mac address is not from the pre configured list can be assigned to a non routable vlan or an isolated vlan which does not have any connectivity into your network just like a guest and then you can have control on that vlan.

But I agree 802.1x will give you more security and control in your network.

You can have a look at these links for 802.1x as well as VMPS

For 8021.1x

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_37_se/configuration/guide/sw8021x.html

For VMPS

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_37_se/configuration/guide/swvlan.html#wp1212223

HTH

Ankur

*Pls rate all helpfull post

802.1x is a good way of doing this. I use this in public areas, but am a little more sadistic and give limited access in some areas. Conference rooms, fall under a Guest VLAN and ACLs that limit access to two dns servers, dhcp, and port 80 and 443 to the i-net.

Other more secure areas, I lock them down into a black-hole vlan, that does nothing but frustrate.