.... for security purpose. Would like to use Cisco equipment. Do I absolutely need to purchase a LAN controller, or can I use a switch? If so, what Cisco switch might be recommended? My Wifi speed is approx. 100mbps (ethernet). Thanks, joe.
What is a "LAN controller"?
The "100mbps (ethernet)" is a peculiar value for "Wifi speed".
A normal case is that each subnet (aka LAN) is in separate physical network (wires, routers, switches).
VLAN technology allows multiple subnets to share hardware. VLAN is less secure than full physical isolation.
The "for security" implies that you have now single subnet for both wireless and wired clients and that you want to move the traffic from wireless clients into separate subnet. The wired traffic between WAN-router and WiFi-AP.
If that is not your goal, then please enlighten us.