Another approach is becoming more popular, because it offers many of the benefits of direct connection, but can still be done at a home without a permanent dedicated Internet phone line. This approach is called PPP (Point to Point Protocol). A related protocol is called SLIP (Serial Line Interface Protocol). PPP is replacing SLIP. For our purposes, we will consider them the same thing. An organization with PPP capability may be set up the same way as the dial in service model. There is a large computer with a permanent direct connection, and a number of people with smaller home computers that want to connect to the larger machine through cables or phone lines. When these machines are connected via PPP, the larger machine has its own IP number, and a bank of temporary IP numbers it is allowed to "check out," like library books. Your home computer must have a special program that knows how to hook up to the large computer and "check out" an IP number. You activate this software, and it makes the connection to the large computer through your modem. As long as this connection is open, your computer has its own albeit temporary IP number. In effect, you have 'faked out' the Internet into believing you have a direct connection.
With a PPP connection, it is really your computer at home with the Internet connection. You can run programs that take advantages of your graphics and sound capabilities (like most web browser programs), and anything that you save will be saved to your own computer, not the large one. When you break off the connection, the IP number you borrowed will be returned to the pool. The next time you utilize this service, you may get a different number.
This approach is not terribly expensive to maintain, and it allows people to take advantages of their own computer's capabilities. The user has to set up the PPP program as well as setting up and installing any client software he wants to use. This can be intimidating, but it gives the user a great deal of power.
A PPP connection is not appropriate for server programs or information. For example, if you wanted to make a web page and make it available to everyone on the Internet, you couldn't do it with a PPP account alone.
