The features and principles of pon technology
PON (Passive OpTIcal Network). PON means that (in the optical distribution network) does not contain any electronic devices and electronic power supplies. The ODNs are all composed of passive components such as optical splitters, and do not require expensive active electronic devices. A passive optical network consists of an Optical Line Terminal (OLT) installed at the central control station and a set of associated Optical Network Units (ONUs) installed at the customer premises. The optical distribution network (ODN) between the OLT and the ONU contains optical fibers as well as passive optical splitters or couplers.
The outstanding advantage of the PON network is the elimination of outdoor active devices, all signal processing functions are done in the switch and in the user's home equipment. Moreover, the initial investment of this access method is small, and most of the funds can be invested only when the user actually accesses. Its transmission distance is shorter than that of the active fiber access system, and the coverage range is small, but its cost is low, no need for a separate machine room, and easy maintenance. This structure therefore makes it economical to serve home users.
PON working principle
The OLT assembles the downlink services that are sent to the ONUs into frames, and sends them to multiple ONUs in a broadcast manner. That is, the optical splitters are divided into N independent signals, and each signal contains frames sent to all specific ONUs. Each ONU extracts only the frames sent to itself, and discards the frames of other ONUs; the uplink data from each ONU to the OLT in the uplink direction is transmitted through a time division multiple access (TDMA) shared channel, and the OLT allocates one transmission time for each ONU. Gap. These time slots are synchronized, so when a data packet is coupled into a fiber, no collisions occur between packets of different ONUs.PON technology features
PON is an access network technology that is positioned in the often-called "last mile", a solution between a service provider, a telecommunications office, and a business or home user.The outstanding advantage of the PON network is the elimination of outdoor active devices, all signal processing functions are done in the switch and in the user's home equipment. Moreover, the initial investment of this access method is small, and most of the funds can be invested only when the user actually accesses. Its transmission distance is shorter than that of the active fiber access system, and the coverage range is small, but its cost is low, no need for a separate machine room, and easy maintenance. This structure therefore makes it economical to serve home users.
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