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Cable Television As a Main Telecommunications

by:TBT     2020-07-30
There are many choices for broadband service providers and the technologies they offer. Cable Television Systems throughout the world use multiple network architectures to deploy their services. One of the most prevalent ones is referred to as HFC (Hybrid Fiber Coax) this is known as a closed system network. That is to say, the signals are not transmitted through the air. They are sealed within a combination of fiber optic and coaxial cables. The technology has been around since the early 1980s. It has undergone major technological advances through innovative design and engineering since its inception. The transport of cable television signals in an HFC system is via a combination of fiber optic (light transmission) and coaxial cables (RF transmission) beginning at a processing station known as the Head-end. A Head-end is much like the Central Office for the telephone company. It is the heartbeat and brains of the network. In Cable Television the Head-end gathers incoming signals of voice, video and data from satellite, microwave and off-air sources. It then processes and combines all of the information, turns it into light and transmits it via laser transmitters onto a fiber optic network. The fiber optic portion of the network is extremely reliable and the transfer of information is at light speed. Before the network can service a business or home, the fiber cable must terminate at what is called an optical receiver. An optical receiver receives the light transmitted by the Head-end through the fiber network and turns it back into RF. It is then transmitted onto coaxial cables which in turn feed RF amplifiers. These amplifiers raise the signals to a high enough level to allow service to the customer base of homes and businesses.
Advantages--The HFC network is capable of all voice, video and data services. For this reason what are referred to as bundled services, are offered by the Service Provider. These services are competitively priced and affordable. Internet speeds are very fast. Phone service is reliable and the picture quality is good. In the United States, video signals transported by the HFC system are already converted to digital and processed so your television can understand them. For this reason, special boxes are not required for most modern televisions to operate. Typically the requirement of a special set top box is when premium or expanded type services are requested by the consumer.
Disadvantages--The HFC system requires a considerable number of electronic devices to work in harmony in order to operate properly. Any failure or maintenance issues with these devices can cause degradation, or temporary discontinuance of service to small or large areas of the system. Recovery time and severity of the problem is dependent upon the device type and where it is located in the network. Hi volume internet traffic can cause a slowdown with internet speeds on an HFC network. The entire network is constructed on existing utility poles and or underground within Public Utility Easements. Mother Nature can wreak havoc with high winds, lightning and general wear and tear resulting in outages and or physical damage to the cables and electronics. But the same holds true for any outdoor utility such as telephone or power.
The HFC system is reliable and a great moderate choice for broadband services for home or business. It is affordable and widely available in most urban, as well as many rural areas.
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