Résumé
A passive optical network (PON) is a fiber-optic telecommunications technology for delivering broadband network access to end-customers. Its architecture implements a point-to-multipoint topology in which a single optical fiber serves multiple endpoints by using unpowered (passive) fiber optic splitters to divide the fiber bandwidth among the endpoints. Passive optical networks are often referred to as the last mile between an Internet service provider (ISP) and its customers. Many fiber ISPs prefer this technology. A passive optical network consists of an optical line terminal (OLT) at the service provider's central office (hub), passive (non-power-consuming) optical splitters, and a number of optical network units (ONUs) or optical network terminals (ONTs), which are near end users. A PON reduces the amount of fiber and central office equipment required compared with point-to-point architectures. A passive optical network is a form of fiber-optic access network. In most cases, downstream signals are broadcast to all premises sharing multiple fibers. Encryption can prevent eavesdropping. Upstream signals are combined using a multiple access protocol, usually time-division multiple access (TDMA). Passive optical networks were first proposed by British Telecommunications in 1987. Two major standard groups, the Institute of Electrical and Electronics Engineers (IEEE) and the Telecommunication Standardization Sector of the International Telecommunication Union (ITU-T), develop standards along with a number of other industry organizations. The Society of Cable Telecommunications Engineers (SCTE) also specified radio frequency over glass for carrying signals over a passive optical network. Starting in 1995, work on fiber to the home architectures was done by the Full Service Access Network (FSAN) working group, formed by major telecommunications service providers and system vendors. The International Telecommunication Union (ITU) did further work, and standardized on two generations of PON. The older ITU-T G.
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Concepts associés (14)
FTTx
Le FTTx (fibre to the...) consiste à amener la fibre optique au plus près de l'utilisateur, afin d'augmenter la qualité de service (en particulier le débit) dont celui-ci pourra bénéficier. On parle également parfois de FITL, pour Fibre in the loop (fibre dans la boucle, sous-entendu locale). Souvent, quand on parle de raccordement des utilisateurs à la fibre optique, il s'agit dans les faits d'un rapprochement du réseau de fibres optiques au client via une paire de cuivre (opérateurs télécom) ou d'un câble coaxial (câblo-opérateur).
Fiber-optic communication
Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of infrared or visible light through an optical fiber. The light is a form of carrier wave that is modulated to carry information. Fiber is preferred over electrical cabling when high bandwidth, long distance, or immunity to electromagnetic interference is required. This type of communication can transmit voice, video, and telemetry through local area networks or across long distances.
Optical Distribution Network
An access network is a type of telecommunications network which connects subscribers to their immediate service provider. It is contrasted with the core network, which connects local providers to one another. The access network may be further divided between feeder plant or distribution network, and drop plant or edge network. An access network, also referred to as an outside plant, refers to the series of wires, cables and equipment lying between a consumer/business telephone termination point (the point at which a telephone connection reaches the customer) and the local telephone exchange.
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