1. Emerging Threats, "CVS Log for sigs/MALWARE/MALWARE_Socks_Proxy," 2008–2010, http://www.emergingthreats.net/cgi-bin/cvsweb.cgi/sigs/MALWARE/MALWARE_Socks_Proxy.
2. Al Iverson, "Al Iverson's DNSBL Resources," DNSB Resource, 2001–2009, http://www.dnsbl.com.
3. Lars Brinkhoff, "HTTP Tunnel," 2008,
http://www.nocrew.org/software/httptunnel.html.
4. JCraft, "JCraft: Code the Craft, Craft the Code," 1998–2009, http://www.jcraft.com/jhttptunnel/.