Cisco IOS

<p>The Internetworking Operating System (IOS) is a family of proprietary <a href="/facts/Network_operating_system/K9MlJLI3">network operating systems</a> used on several <a href="/facts/Router_(computing)/Nh5cIyVf">router</a> and <a href="/facts/Network_switch/CnvmhNYT">network switch</a> models manufactured by <a href="/facts/Cisco/ocDgQt6T">Cisco Systems</a>. The system is a package of routing, switching, internetworking, and telecommunications functions integrated into a <a href="/facts/Computer_multitasking/Q4acPNMv">multitasking</a> operating system. Although the IOS code base includes a <a href="/facts/Cooperative_multitasking/svrQ2DMM">cooperative multitasking</a> kernel, most IOS features have been ported to other kernels, such as <a href="/facts/Linux/9FvCKSTq">Linux</a> and <a href="/facts/QNX/gBsfJvcB">QNX</a>, for use in Cisco products.
</p><p>Not all Cisco networking products run IOS. Exceptions include some <a href="/facts/Cisco_Catalyst/S8pCJH0o">Cisco Catalyst</a> switches, which run <a href="/facts/Cisco_IOS_XE/sMm4qPkf">IOS XE</a>, and <a href="/facts/Cisco_ASR/vB4rEcxc">Cisco ASR</a> routers, which run either IOS XE or <a href="/facts/Cisco_IOS_XR/lJnKM8tC">IOS XR</a>; both are Linux-based operating systems. For data center environments, <a href="/facts/Cisco_Nexus_switches/d2QhQdVr">Cisco Nexus</a> switches (<a href="/facts/Ethernet/nMfhU8tU">Ethernet</a>) and Cisco MDS switches (<a href="/facts/Fibre_Channel/C7C0yreb">Fibre Channel</a>) both run <a href="/facts/Cisco_NX-OS/PU2fVKXt">Cisco NX-OS</a>, also a Linux-based operating system.
</p>

Cisco IOS open-in-new

Cisco IOS