tcp/ip
1. gopher://gopher-chem.ucdavis.edu/11/Index/Internet_aw/Intro_the_Internet/intro.to.ip/
2. http://pclt.cis.yale.edu/pclt/comm/tcpip.htm
3. http://oac3.hsc.uth.tmc.edu/staff/snewton/tcp-tutorial/
4. http://www.psc.edu/networking/perf_tune.html
5. http://www.rtd.com/pcnfsfaq/faq.html