A network switch is a computer networking device that connects network segments. Low-end network switches appear nearly identical to network hubs, but a switch contains more "intelligence" than a network hub. Network switches are capable of inspecting data packets as they are received, determining the source and destination device of that packet, and forwarding it appropriately. By delivering each message only to the connected device it was intended for, a network switch conserves network bandwidth and offers generally better performance than a hub.
Catalyst is the brand name for a variety of network switches sold by Cisco Systems. Being a popular brand, the Catalyst switch is a regular in many IT infrastructures.
Issues with the switch could be the source of critical infrastructural problems such as excessive bandwidth usage, slow delivery of data packets, or even worse, loss of data during transit!
If such issues are to be averted, then the performance of the Catalyst switch should be monitored 24 x 7.