Quote Originally Posted by angiest View Post
They are also a major player in the embedded Linux market (which webOS is). On their MDS series of SAN (storage) switches, the SAN-OS is a linux kernel with various added parts. Their next generation operating system, designed for the Nexus convergence switches (NX-OS) is based on SAN-OS. I assume IOS is also a Linux kernel. Some of the Linksys products are based on Linux as well, and the various wrt third party firmwares grew out of the GPL'd parts of Linksys' firmware.
IOS isn't Linux. It's a custom kernel written in 1987 by William Yeager.

Cisco IOS - Wikipedia, the free encyclopedia