最早思科是只做路由器不做交换机，当时做交换机的厂商已经很多了，所以思科想进军交换机界就走了一条收购的道路，被收购的生产交换机的厂商叫catalyst，而且还保留他们自己的IOS，所以现在还是分Cisco IOS和Cisco catOS2种。
cisco catalyst系列一定是交换机：
Cisco Catalyst 4500 Series Switches Cisco Catalyst 3850 Series Switches Cisco Catalyst 3750 Series Switches Cisco Catalyst 3750-E Series Switches Cisco Catalyst 3750-X Series Switches Cisco Catalyst 3650 Series Switches Cisco Catalyst 3560 Series Switches Cisco Catalyst 3560-E Series Switches Cisco Catalyst 3560-X Series Switches Cisco Catalyst 2960 Series Switches Cisco Catalyst 2960-Plus Series Switches Cisco Catalyst 2960-S Series Switches Cisco Catalyst 2960-SF Series Switches Cisco Catalyst 2960-X Series Switches Cisco Catalyst 3560-C Series Switches Cisco Catalyst 2960-C Series Switches Cisco Catalyst 6800 Series Switches Cisco Catalyst 6500 Series Switches Cisco Catalyst 6500 Virtual Switching System 1440 Cisco Catalyst 4900 Series Switches Cisco Catalyst 4500 Series Switches Cisco Catalyst 4500-X Series Switches
