For two computers to talk to each other, they must share a common language. There are a number of common communication languages ("protocols") for computers. The most common language at this writing is TCP/IP, also referred to as the "Internet protocol family".
TOPS TCP/IP is an implementation of the TCP/IP protocol family by TOPS, a Sun Microsystems Company. TOPS Terminal calls on TOPS TCP/IP to handle the details of communication with other computers over Appletalk or Ethernet.
TOPS TCP/IP is contained in a single file which must go into the System Folder. If your environment requires it, TOPS TCP/IP can be configured through the Control Panel.
Because TOPS TCP/IP is a Control Panel file, it will only work on Apple System 4.1 and Finder 5.5, or higher.
If you will be using TOPS Terminal only for modem communications, you should not have TOPS TCP/IP in your system folder, because it takes about 50K of memory away from applications, and slows down the Mac's startup sequence by a few seconds.
TCP/IP is network- and computer-independent. That is, it bridges hardware differences between the two computers and even between their local networks. For instance, a Mac on Appletalk can talk to a Sun on Ethernet, despite their differences, because they both speak TCP/IP protocols.
Because of TCP/IP's independence of hardware, very large TCP/IP networks can be established. One called the ARPANET goes all over the world, linking many different kinds of networks and allowing any of the thousands of attached computers to speak with any of the others. (The ARPANET was established by the United States' Department of Defense Advanced Research Projects Agency, and access to it is restricted.)
More detailed information on the workings of TCP/IP is available. It is suitable for those with a fair degree of computer background. See the subtopics to the right.
