Cable modem: Encyclopedia II - Cable modem - Cable Internet Access

Cable modem - Cable Internet Access

The term cable Internet access (or simply cable) refers to the delivery of Internet service over this infrastucture.

Along with DSL technology, cable modems ushered in the age of broadband Internet access in developed countries. Cable modems usually deliver speeds comparable to that of DSL, however, DSL modems generally have better upload speeds. Prior to the availability of such systems, Internet access involved slow dial-up access over a public switched telephone network.

Three often cited disadvantages of cable Internet are:

1. Users in a neighborhood share the available bandwidth provided by a single coaxial cable line. Therefore, connection speed can vary depending on how many people are using the service at the same time. Often the idea of a shared line is seen as a weak point of cable Internet access. From a technical point of view, all networks, including DSL services, are sharing a fixed amount of bandwidth between a multitude of users — but because cable networks tend to be spread over larger areas than DSL services, more care must be taken to ensure good network performance.
2. A more significant weakness of cable networks using a shared line is the risk of loss of privacy, especially considering the availability of hacking tools for cable modems. This issue is addressed by encryption and other privacy features specified in the DOCSIS (Data Over Cable Service Interface Specification) standard used by most cable modems.
3. Many cable Internet providers are reluctant to offer cable modem access without tying it to a cable television subscription. This has ramifications similar to those of the lack of naked DSL.

Adapted from the Wikipedia article "Cable Internet Access", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki