Rack 12 & 13 are designed to use with Netmetric Solution Khawar Butt's CCIE Security 2.0 workbook.Routers support 12.3, 12.3T firewall IOS features set including the 2 x 3550 L2/L3 Multilayers Switches. The rack is prewired to support Khawar's Security workbook labs.