Lance Spitzner Whitepapers - Papers on armoring Solaris, Linux and configuring firewalls. - http://www.spitzner.net/
Building a Bastion Host Using HP-UX 11 - Recipe by Kevin Steves for protecting HP-UX 11. - http://secinf.net/unix_security/Building_a_Bastion_Host_Using_HPUX_11.html
Communications-Electronics Security Group - Independently evaluates and certifies the level of trust that may be placed in IT security features. - http://www.cesg.gov.uk/