Actually in security itself - is also wide

There is VA - aka Hacking team
SOC - Security Operation where IDS skillset is required
Firewall and Proxy - Perimeter Security, ACL and etc
Application Security
Malware Forensic
System Forensic

GSEC is a good start for you to understand IT security Better. But it might be too beginner for some. I had friends who complain that.

Just sharing of info.