Terms you'll need to understand:
RFC 2196, "Site Security Handbook"
Threat types
Structured
Unstructured
External
Internal
Packet sniffing
IP spoofing
Denial of service (DoS)
Distributed denial of service (DDoS)
Strong password
Vulnerability
Exploit
Man-in-the-middle attack
Trust exploitation
Techniques you'll need to master:
Recognizing the importance of security and security policy
Listing the types of network attacks
Listing the types of network threats
Mitigating different attacks