TCP/IP Protocol Stack for Newbies

First attempt at a TCP/IP primer. It's dumbed down for newbies, and focuses on functions at the network transport layers.

It's going to be a series, so there will be some more that provide info on topics that preceed the concepts of this one, like the OSI model (dumbing down the OSI model...there's a challenge! :D ), and data-link layer TCP/IP functions like MAC and LLC.

There will also be some that build on it, like upper layer TCP/IP functions, and IP addressing and subnetting. Tell me what you think, and I appreciate any suggestions on improvements to it.

I'd appreciate it if you could jump a couple of lessons and go straight to sub-netting :)