A hybrid fiber coaxial (HFC) network is a telecommunication technology in which optical fiber cable and coaxial cable are used in different portions of a network to carry broadband content (such as video, data, and voice).

Using HFC, a local CATV company installs fiber optic cable from the cable head-end (distribution center) to serving nodes located close to business and residential users and from these nodes uses coaxial cable to individual businesses and homes.

An advantage of HFC is that some of the characteristics of fiber optic cable (high bandwidth and low noise and interference susceptibility) can be brought close to the user without having to replace the existing coaxial cable that is installed all the way to the home and business.

Both cable TV and telephone companies are using HFC in new and upgraded networks and, in some cases, sharing the same infrastructure to carry both video and voice conversations in the same system.

Here are lists four reasons why cable TV and telephone companies are upgrading facilities to HFC:

1) The use of fiber optic cable for the backbone paths allows more data to be carried than coaxial cable alone.

2) The higher bandwidth supports reverse paths for interactive data flowing back from the user.

3) That portion of the infrastructure with fiber optic cable is more reliable than coaxial cable. Reliability is perceived as more important in an interactive environment.

4) Fiber optic cable is more efficient for interconnecting cable TV or phone companies that are consolidating with geographically adjacent companies.


If you want to read a little more into it..........here ya go.....

The term hybrid fiber coax (HFC) was derived from the structure of the cable architecture, which uses optical transmitters and fiber nodes interspersed with long cascades of radio frequency (RF) coax amplifiers. In this network, the fiber provides the high-speed backbone, and the coax is used to connect end users to the backbone. The coaxial portion of the HFC networks uses a tree-and- branch topology (CableLabs diagram) with a shared LAN-like structure. Usually, each optical node serves 500 to 2,000 homes.Within this structure, the downstream direction broadcasts RF signals over the 54-860 MHz spectrum.

To maintain acceptable signal-to-noise ratios to every subscriber on the cable plant, bandwidth beyond 860 MHz cannot be effectively utilized in the current design.Current HFC networks are designed to provide asymmetrical services - i.e. broad cast services from the cable operator to the subscriber - with a limited return path.

Due to the anticipated popularity of bi-directional services such as VOD (Video-on -Demand), high-speed Internet and VoIP (Voice over IP), cable operators have begun massive plant upgrades that will eventually provide these services nationally.

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