Cable Television - Other Cable-based Services

Other Cable-based Services

Coaxial cables are capable of bi-directional carriage of signals as well as the transmission of large amounts of data. Cable television signals use only a portion of the bandwidth available over coaxial lines. This leaves plenty of space available for other digital services such as cable internet, cable telephony and wireless services, using both unlicensed and licensed spectrum.

Broadband Internet is achieved over coaxial cable by using cable modems to convert the network data into a type of digital signal that can be transferred over coaxial cable. One problem with some cable systems is the older amplifiers placed along the cable routes are unidirectional thus in order to allow for uploading of data the customer would need to use an analog telephone modem to provide for the upstream connection. This limited the upstream speed to 31.2k and prevented the always-on convenience broadband internet typically provides. Many large cable systems have upgraded or are upgrading their equipment to allow for bi-directional signals, thus allowing for greater upload speed and always-on convenience, though these upgrades are expensive.

In North America, Australia and Europe many cable operators have already introduced cable telephone service, which operates just like existing fixed line operators. This service involves installing a special telephone interface at the customer's premises that converts the analog signals from the customer's in-home wiring into a digital signal, which is then sent on the local loop (replacing the analog last mile, or Plain old telephone service (POTS)) to the company's switching center, where it is connected to the Public switched telephone network (PSTN). The biggest obstacle to cable telephone service is the need for nearly 100% reliable service for emergency calls. One of the standards available for digital cable telephony, PacketCable, seems to be the most promising and able to work with the Quality of Service (QOS) demands of traditional analog Plain old telephone service (POTS) service. The biggest advantage to digital cable telephone service is similar to the advantage of digital cable TV, namely that data can be compressed, resulting in much less bandwidth used than a dedicated analog circuit-switched service. Other advantages include better voice quality and integration to a Voice over Internet Protocol (VoIP) network providing cheap or unlimited nationwide and international calling. Note that in many cases, digital cable telephone service is separate from cable modem service being offered by many cable companies and does not rely on Internet Protocol (IP) traffic or the Internet.

Beginning in 2004 in the United States, the traditional cable television providers and traditional telecommunication companies increasingly compete in providing voice, video and data services to residences. The combination of TV, telephone and Internet access is commonly called triple play regardless of whether CATV or telcos offer it.

More recently, several US cable operators have begun offering wireless services to their subscribers. Most notably was the September 2008 launch of Optimum Wi-Fi by Cablevision. This service is made available, at no additional cost, to Optimum Broadband subscribers, and is available at over 14,000 locations across Long Island, NY, parts of NJ and CT. Cablevision has reported a double digit reduction in subscriber churn since launching Optimum Wi-Fi, even as Verizon has rolled out FiOS, a competitive residential broadband service in the Cablevision footprint. Other Tier 1 cable operators, including Comcast, have announced trials of a similar service in sections of the US Northeast.