1.OLT networking architecture:

Optical access network is the access network with light as the transmission medium, instead of copper wire. It is used to connect to every family. The optical access network is composed of three parts: OLT (Optical Line Terminal, optical line terminal) and ONU (Optical Network Unit, optical network unit) and ODN (Optical Distribution Network, optical distribution network). The core component of optical access network.

OLT is the core component of the optical access network, which is equivalent to the switches or routers in the traditional communication network, and it is also a multi service platform. It is usually placed at the local end to provide a user oriented passive optical fiber network interface. Its main functions are:

• The upper layer network of the upper link completes the uplink access of PON (Passive Optical Network).

• Through the ODN network (composed of optical fiber and passive light splitter), connect the user terminal device ONU. It realizes the control, management and ranging functions of ONU.

ONU, a client device in optical network, is placed on the user side and used with OLT to realize the function of two layers and three layers of Ethernet, providing users with voice, data and multimedia services. Its main functions are:

• Choose to receive data sent by OLT.

• Respond to the administrative commands issued by OLT and make corresponding adjustments.

• The user's Ethernet data is cached and sent to the uplink direction in the OLT distribution window.

• Other user management functions.

In short, OLT is like a commander, directing all ONU soldiers to provide low-cost and high-speed communication services, and to connect the earth to us more closely by technology of light and technology to change our lives.