You probably skip the network + depending on how much you know. But its still good reading. If you can get trancenders they really help with preparing for the CCNA. If you want to really understand TCP/IP there is a book every network person I know has including myself. It is TCP/IP Illustrated, Volume 1, great book I have my CISSP and soon my Solaris Security Cert. I am going to be starting on my SANS certs also. It is tough work but the more you actually learn and not just go through the motions to get a Cert the better off you will be. Certs are great if you know your stuff but these days if you don't they won't help you as much as they used to.