Cisco IOS: The Operating System for Cisco Routers and Switches

Cisco IOS (Internetwork Operating System) is a proprietary operating system used in Cisco networking devices such as routers and switches. It provides the functionality needed to configure, monitor, and manage the network devices. Cisco IOS is designed to be highly reliable and scalable, with features such as routing protocols, security, Quality of Service (QoS), and network management. Cisco IOS also supports a command-line interface (CLI) for configuration and administration.