IN THIS CHAPTER
OSI networking model
Understanding IP addressing
The network is a big place. It encompasses the Internet, wide area networks, metropolitan area networks, local area networks, and any other network type you can think of. In its simplest terms, the network is a source of connectivity between two systems. It can be a proprietary link between two legacy machines, or open protocols all the way with the latest generation of networked enterprise systems, Linux.
The general concept of a network is fairly well understood by most people today. Ten years ago, there weren't that many people familiar with the term "network" in a digital communications sense. With the emergence of the Internet, that has all changed. Try finding a 12-year-old who does not know what the Internet is.
We all know what a network is, but how systems interact and become a network is something most people take for granted. Linux is a big player in the Internet. It provides a huge amount of the web servers you see out there. Apache itself serves more of the Internet than any other web server, and it is all open source. The TCP/IP protocol is an open protocol, as are the many services based on TCP/IP.
One thing about the Internet that we sometimes forget is that it was and, in some sense, still is a frontier for the technical elite to be able to define and sculpt technology in an open forum, in view of peers. This leads to ...