This chapter covers ways to harden your system further to reduce the likelihood of a successful break-in. The topics covered include:
"Protecting User Sessions with SSH" on page 409
"Virtual Private Networks (VPNs)" on page 422
"Pretty Good Privacy (PGP)" on page 430
"Using GPG to Encrypt Files the Easy Way" on page 431
"Firewalls with IP Tables and DMZ" on page 446
"Firewalls with IP Chains and DMZ" on page 514