Connection Types
POTS
A POTS connection is extremely slow, but it is available wherever there is a telephone. A modem uses the telephone line to transmit and receive data. This method of connection is known as dial-up.
Cable
A cable Internet connection does not use telephone lines. Cable uses coaxial cable lines originally designed to carry cable television. Like DSL, cable offers high speeds and an always-on connection, which means that even when the connection is not in use, the connection to the Internet is still available. Many cable companies offer telephone service as well.
DSL
DSL, like ISDN, allows multiple devices to share a single telephone line. DSL speeds are generally higher than ISDN. DSL allows the use of high-bandwidth applications or multiple users to share the same connection to the Internet. In most cases, the copper wires already in your home or business are capable of carrying the signals needed for DSL communication. There are limitations to DSL technology. DSL service is not available everywhere, and it works better and faster the closer the installation is to the telephone provider's Central Office (CO). Also, DSL is much faster when receiving data over the Internet than it is when sending it. In some cases, the lines that are in place to carry telephone signals do not technically qualify to carry DSL signals.
Satellite
For people who live in rural areas, broadband satellite Internet connections provide a high-speed connection that is always on. A satellite dish is used to transmit and receive signals to and from a satellite that relays these signals back to a service provider. The cost of installation and the monthly service fees are much higher than those for DSL and cable subscribers. Heavy storm conditions can degrade the quality of the connection between the user and the satellite, or the satellite to the provider, slowing down or even disconnecting the connection.
ISDN
ISDN offers faster connection times and has faster speeds than dial-up, and allows multiple devices to share a single telephone line. ISDN is very reliable because it uses POTS lines. ISDN is available in most places where the telephone company supports digital signaling.
Cellular
Many types of wireless Internet services are available. The same companies that offer cellular service may offer Internet service. PCMCIA and PCI cards are used to connect a computer to the Internet. The service is not available in all areas.