In the application of PON technology, the OLT equipment is an important device, which realizes the function of: 1. Connected with the front-end (converged layer) switch with the network cable, the conversion into a light signal, with a single fiber and the user side of the optical splitter. 2. Realize the control, management, ranging and other functions of the user-end equipment ONU. 3. Olt equipment and ONU equipment, is also a photoelectric integrated equipment.
Epon network consists of three parts, Olt, Odn and ONU. Olt belongs to access network business node side equipment, through the SNI interface and the corresponding business node equipment connected to complete access to the network business.
The upstream access of the PON network is mainly completed and connected with the ONU device through the PON port through the ODN network (optical fiber and passive splitter), generally using 1:32 or 1:64 to form the entire PON network. The general Pon port is connected by single fiber and ODN net, the splitter does 1: N (N, 4, 8, 16, 32, 64, etc.), ONU downlink adopts broadcast mode, and ONU equipment is selectively received. The uplink is shared.
The development of PON technology has undergone the process of apon/bpon, Epon and Gpon, and is evolving toward 10G Pon and WDM Pon. Because of the flexible deployment and lower cost, PON technology has been widely used as the main mode of the current fixed broadband access.
Olt on-board equipment, if the optical signal is too strong (sometimes because the distance short light signal loss is small) need to add attenuator. Olt ONU, in between the two light splitter.