Crash course networkbasics

At the department where I work, my collegues don’t really know the network basics.

I discovered it when I had a discussion like (note there are no routers involved in the network we discussed!):

Coll: That was weird… the computers couldn’t communicate with eachother.
Me: Explain… how did you config it?
Coll: Well… one system has IP-addres 192.168.0.10 and the other one 192.168.1.50, with subnet 255.255.255.0!
Me: Well… to be honest, that is quite normal…
Coll: Why?

So… I made a crashcourse with networkbasics. It covers the next topics:

  • What is communicating
  • Models of communicating (simplex/half-duplex/full-duplex)
  • The OSI-Model and the different layers
  • The global knowledge of Ethernet II and a hub versus a switch
  • IP in general
  • IPv4 networks with subnets a network classes
  • The Transmission Control Protocol
  • The User Datagram Protocol
  • Discuss a TCP packet sniffed by Ethereal
  • The movie Warriors of the Net