Optical access Network is a network of optical transmission media, replacing copper wire, used for access to each family. Optical access network is made up of Olt (optical line Terminal, optical circuit terminals) and ONU (Optical Network Unit, Optical Network Unit) and ODN (optical distribution Network, optical distribution network) are composed of three parts, of which Olt and ONU are the core components of optical access networks. The core components of optical access networks.
OLT is the core component of optical access network, which is equivalent to the switch or router in the traditional communication network, and it is also a multi service platform. Generally placed on the local side, providing a user-oriented optical fiber interface for passive optical networks. The main functions of this system are:
Upper layer Network, complete pon (passive optical Network, passive optical network) network uplink access.
The ODN network (composed of optical fiber and passive optical splitter) is used to ONU the client device. It realizes the function of controlling, managing and ranging of the ONU of the client equipment.
ONU, is the user-end equipment in optical network, placed on the user side, and Olt with the use of Ethernet two-layer, three-layer function, to provide users with voice, data and multimedia services. The main functions of this system are:
Select the data data sent by the Olt.
Responds to the management commands issued by OLT and adjusts accordingly.
Caches the user's Ethernet data and sends it up in the Olt assigned Send window.
Other user management features.
In short, Olt, like a commanding officer, directs the ONU to provide us with inexpensive and high-speed communications services that connect the Earth more closely together and technology to change life.