The TCP/IP Model in a Nutshell

• Physical layer:

• • Physics. Hard stuff. Not very exciting either.

• Datalink layer:

• • How a packet gets from one to host the next.

• Network layer:

• • How a packet gets from the source host to the destination host.

• Transport layer:

• • How a message from an application running on a source host gets to a peer application running on a destination host.

• Application layer:

• • How an application formats and sends information.