CCNA for Dummies

Here’s a CCNA guide that’s actually fun — but don’t worry, you won’t sacrifice accuracy. Lead author Ron Gilster formerly ran one of Cisco’s Regional Training Academies, so he knows this stuff. It’s all here: the OSI reference model, router basics, commands, and models; key protocols; network addressing, subnetting, and security; LAN switching; WANs; and much more.