POL all-optical network introduction

In recent years, the intelligence and informatization of all walks of life has shown an accelerated development trend, and applications such as mobile office, high-definition video conferencing, and cloud services have almost become standard equipment for enterprises. At the same time, new network requirements such as bandwidth upgrades, ubiquitous access, and IoT integration are becoming more and more urgent, and media upgrades have become a new option for enterprises to solve network problems.

POL (Passive Optical Local Access Network) is a new campus network construction method that replaces copper cables with optical fibers. In the current market, the POL network based on optical fiber transmission is becoming more and more intense.

What is POL all-optical network? Copper cables (including network cables and twisted-pair cables) used to be the main transmission medium for accessing networks, but the inner core of copper cables is copper, which is expensive and has limited transmission distances. Later, optical fiber began to rise. As a new type of communication medium, it is light in weight, good in flexibility, small in size, low in cost, and highly available. Most importantly, optical fiber has large transmission capacity and longer transmission distance.

The POL all-optical network consists of core switches, OLT, ODN, ONU, service terminals, etc. Each device plays an important role, among which OLT, ODN, and ONU are the three most critical devices for POL.

The POL all-optical network is not only a replacement and upgrade of the medium, but also a change of the architecture. Based on the huge advantages of optical fiber transmission, the transmission network of operators has already adopted optical fiber transmission. In 2008, the three major operators started the optical fiber in and copper out of the access network on a large scale, and adopted the FTTB/FTTH mode to deploy optical fiber to corridors and households. Greatly improved the network experience for home users. The optical entry and copper exit of the access network uses PON (Passive Optical Network, Passive Optical Network) technology. While the medium uses optical fiber to replace copper cables, PON uses passive point-to-multipoint (P2MP, Point to Multiple Point ) technology has brought about changes in the network architecture, making the network flat and lower deployment costs. At present, my country has achieved great success in home broadband.