II-The Internet

The Internet is best known as the biggest computer network in the world. It allows its users to communicate with computers all around the world, through such applications as electronic mail, remote login or file transfer.

Its size is what made it most interesting to our project. With a total number of 3,212,000 computers connected (this figure was compiled in July 1994, and is now probably out of date, since the growth rate of the Internet was then estimated at +81% a year), the Internet could provide a lot of computing power, drawn from the unused cycles in most of these machines, but also an environment of maximum complexity.
Maximum complexity because, contrary to what it appears to be from the user's point of view, the Internet is not a computer network. It is rather, as its name suggest, an internetwork, which allows hosts on roughly 46,000 different networks to exchange information.

What makes the Internet possible is the TCP/IP protocol suite. It provides the necessary interface between heterogeneous network technologies and the application programs which are only the visible tip of the Internet iceberg.
The network version of Tierra being such an application program, learning how to interface it with the TCP/IP protocols was most important. Furthermore, we will later see how knowledge of the workings of the protocols themselves, beside being helpful for the network programmer, can be used to design more efficiently the interface between the Tierran creatures and Tierra itself.