Transferring data over the Internet requires a data or phone line to connect to the Internet Service Provider (ISP). Faster connections usually cost more and deciding the appropriate connection depends upon how much money you are willing to spend and how important is transfer speed to you. The services identified cost different amounts per month and some may not be available in your area.
Connecting to the Internet from home requires a special type of modem connection. The two methods available are Point to Point Protocol (PPP) or Serial Line Internet Protocol (SLIP) Anyone can obtain Internet access from home by contacting an ISP and
paying a monthly fee. Current rates vary from $9.00 to $50.00.
When accessing the Internet from home, we use a modem that sends a signal from our computer through the phone lines to a bank of modems connected to the PPP server. The two modems go through a negotiation process called "handshaking" that determines what speed and data transfer protocols to use.
The modems usually can be accessed twenty-four hours a day but they are available on a first come first serve basis. Once a connection is established with the PPP server, the PPP server tricks the network into thinking we have a direct connection by providing a temporary IP address to your computer. The PPP server contains a huge database of IP addresses that are delivered over the phone lines to your computer. When the modem connection drops, the IP address will be reassigned to another computer.
The lowest cost and probably the slowest is a modem connection with speeds up to 56,000 bits per second. You will notice that you rarely will receive data that fast but your modem has that capability.
Frame Relay connections are popular among schools because they offer a guarantee data transfer rate of 56,000 bits per second. While that may not seem like much, most schools don't need that much at any one time. Another advantage of Frame Relay is the low monthly cost and most of the Phoenix metropolitan area phone lines are configured to handle Frame Relay data without any additional wiring costs to the school.
Cox Cable offers a new service called Cable Modems that offers data transfer rates up to 10 million bits per second. The cable modem acts like a shared ethernet connection and your transfer rate will depend upon how many people are using your network node. (More people means slower connection.)
US West has several services to offer but the most popular is Asymmetric Digital Subscriber Line (ASDL). ASDL allows you to use your phone and connect to the Internet at the same time. ASDL's connection will offer transfer rates up to 800,000 bits per second depending on which service you select.
Small to medium size companies with the need to transfer large quantities of data at a time should consider a dedicated line. T-1 lines are able to transfer data at speeds of 1,544,000 bits per second. The College's massive data transfer requirements are met with T-3 lines capable of transferring data at 45 million bits per second.
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