More Links.......

http://www.protocols.com/pbook/images/tcpipmap.gif
http://www.certificationkits.com/tcpiptopics/7layerosimodel.html
http://www.jodies.de/ipcalc
http://www.subnetmask.info/
http://www.tech-faq.com/subnet-calculator.shtml
http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
http://docs.hp.com/en/B2355-60130/linkloop.1M.html

Thx
Randy