The document discusses various methods for locking down a FreeBSD installation, including establishing a security policy, hardening access controls, and monitoring the system. Some key points covered are: - Establish a default deny security policy with authentication required for all access and logging of all exceptions. - Hardening involves securing the network stack, enabling a firewall, restricting inetd, using TCP wrappers, and implementing IPSec. - Additional hardening includes removing known vulnerabilities, increasing the secure level, protecting against resource exhaustion, and restricting services. - Intrusion detection involves tools like Tripwire, SysTrace, Snort, and honeypots, while auditing focuses on authentication and monitoring logs.