4 links
Cisco IOS in a Nutshell
oreilly.com
O'Reilly & Associates guide to configuring for TCP/IP protocol family, user interface, configuring lines and interfaces, access lists, routing protocols, dial-on-demand routing, se…
Cisco IOS Operating System
frigate.com
Brief, clear description, by OS and network consultants, Frigate Networks.
Telconi Terminal for Cisco IOS
telconi.com
A network management application giving experts a visual configuration editor and specialized terminal emulation for any Cisco IOS based devices, such as routers and switches.