About Internet Access

There are a variety of ways to access the Internet. Most online services, such as America Online, offer access to some Internet services. Net Zero and Earthlink, People PC are just a few of the popular Internet providers. Computers and devices that allocate resources for a network are called servers.

Voice band modems allow digital data to flow over the telephone company's traditional telephone network by performing a digital to analog conversion for transmission onto the network and vice versa on the receiving end. The only requirement for modems is that each end of the call must have a compatible modem. In essence, this makes modem connections the most widely used form of data communications available today. However, modems are limited by the telephone company's voice bandwidth service. While modem interfaces are standardized, a number of different protocols for formatting data to be transmitted over telephone lines exist. Most modems have built-in support for the more common protocols -- at slow data transmission speeds at least, most modems can communicate with each other. At high transmission speeds, however, the protocols are less standardized.

Aside from the transmission protocols that they support, the following characteristics distinguish one modem from another:

• BPS: How fast the modem can transmit and receive data. At slow rates, modems are measured in terms of baud rates. The slowest rate is 300 baud (about 25 cps). At higher speeds, modems are measured in terms of bits per second (bps). The fastest modems run at 57,600 bps, although they can achieve even higher data transfer rates by compressing the data. Obviously, the faster the transmission rate, the faster you can send and receive data. Note, however, that you cannot receive data any faster than it is being sent. If, for example, the device sending data to your computer is sending it at 2,400 bps, you must receive it at 2,400 bps. It does not always pay, therefore, to have a very fast modem. In addition, some telephone lines are unable to transmit data reliably at very high rates.
• Voice-data: Many modems support a switch to change between voice and data modes. In data mode, the modem acts like a regular modem. In voice mode, the modem acts like a regular telephone. Modems that support a voice/data switch have a built-in loudspeaker and microphone for voice communication.
• Auto Answer: An auto-answer modem enables your computer to receive calls in your absence. This is only necessary if you are offering some type of computer service that people can call in to use.
• Data Compression: Some modems perform data compression, which enables them to send data at faster rates. However, the modem at the receiving end must be able to decompress the data using the same compression technique. OnSpeed’s solution to Internet connections on Broadband is software you download that uses nine patent approved compression techniques that increases existing Internet connections up to five times on dial up and three times faster on Broadband. One of the things that should be noted is that due to the increased compressions, the quality of the picture is diminished. So you have to decide if the speed is worth the loss of visual quality.
• Flash memory: Some modems come with flash memory rather than conventional ROM, which means that the communications protocols can be easily updated if necessary.
• Fax capability: Most modern modems are fax modems, which means that they can send and receive faxes.

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