Linux Security Home Page:
http://www.ecst.csuchico.edu/~jtmurphy/
Linux Security Alerts:
http://www.aoy.com/Linux/Security/
Linux Security Tools:
http://www.txdirect.net/users/mdfranz/trinux.html
QMail, an alternative to sendmail and considered more secure: http://www.qmail.org/
Secure Shell Home Page:
http://www.cs.hut.fi/ssh/
SniffIt can be obtained from the following URL:
http://alamo.satlug.org/~mdfranz/sniffit.0.3.5.tar.gz
Practical UNIX and Internet Security, by Simson Garfinkel and Gene Spafford. O'Reilly and Associates, 1996.
Linux Network Administrator's Guide by Olaf Kirch, O'Reilly and Associates, 1995.
``Wrap a Security Blanket Around your Computer'', Lee E. Brotzman, Linux Journal, Issue 40, August 1997: http://www.ssc.com/lj/issue40/2180.html
``Maximizing Linux Security: Part 1'', Frisch, ÆLeen, Linux Journal, Issue 21, January 1996: http://www.ssc.com/lj/issue21/1170.html
``Maximizing Linux Security: Part 2'', Frisch, ÆLeen, Linux Journal, Issue 22, February 1996: http://www.ssc.com/lj/issue22/1206.html
All listings referred to in this article are available by anonymous download in the file ftp://ftp.ssc.com/pub/lj/listings/issue58/3062.tgz.