Skills of the Hacker

1. Should possess Extensive Knowledge – This means that you need to know everything about everything. Though it sounds unrealistic, but this is true. 
2. Should already be a security expert in other areas (like perimeter security etc). 
3. Should have experience as network or system administrator. The concept is pretty simple, you can’t hack a PBX box, if you don’t know how to operate one. Or you can’t hack a Linux/Unix box if you don’t know various Unix commands. 
4.  Should have good working knowledge of various OS. 
5. Good understanding of ports, protocols and TCP/IP. 
6. You also need to have a good understanding of common security vulnerabilities and their fixes like buffer overflow etc. 
7. Good understanding of the various security tools and techniques.