Principle of optical fiber communication is first necessary to transfer in the sender information (such as voice) into electrical signals, and then modulated onto the laser beam emitted from the laser, so that the intensity of light with the electric signal amplitude (frequency) changes, and sent through an optical fiber; at the receiving end, the detector receives the optical signal converts it into an electric signal, after demodulation to restore the original information.

All-optical switching is the future direction of development, but also from the current development trend, this "future" is not far away. Many in the industry view: ROADM-based networking and scheduling is not sensitive to the rate applicable to ultra-high-speed optical networking and scheduling transmission systems, but also can greatly reduce power consumption and floor room. After years of gradual improvement technology, functionality and performance, CDC-F ROADM (ie colorless and directionless without conflict and supports flexible grid capacity reconfigurable optical forked Multiplexer) device has matured, basically solved the light layer networking encountered many problems. Some foreign operators in the deployment of 100G networks have begun to do large particles using ROADM traffic scheduling, a direct transition to an all-optical network. March 2015, Verizon announced the adoption of Ciena and Cisco's packet optical transport platform Metro 100G deployment, CDC-F ROADM technology for the first time to get a commercial scale. In the same month, Alcatel-Lucent announced that Verizon will use its latest CDC-F ROADM technology to upgrade Verizon's long-haul optical transport network.

(1) Light transmitter
Light transmitter is to achieve electrical / optical conversion of Optical. It consists of a light source, driver and modulator. Its function is to electrical signals from the electrical end machine for light emitted from the light source is modulated, become modulated light, and then the modulated optical signal is coupled into an optical fiber or optical cable to transmit. Electric end machine is conventional electronic communication devices.

PTN Layer 2 technologies can be seen as a simplified version of the mechanism and OAM enhancements combination. In the realization of the technology, the two main technical PBT and T-MPLS will be a substitute for SDH, rather than the IP/MPLS competitors, similar to its network theory, are based on end to end, bidirectional point to point connection, and provides a central management, within 50 milliseconds protection switchover; either can be used to implement SONET/SDH to packet switching transition, in the protection of existing transmission resources, it can be similar to the existing SDH network functions to implement the network packet switched network transformation.

Software-defined networking (Software Defined Network, SDN), is a new kind of network innovation Emulex network architecture, network virtualization is an implementation of its core technology OpenFlow network devices through the control and data planes separated, in order to achieve the flexible control of network traffic, the network as a conduit to become more intelligent.

Currently, China Mobile's existing network has more than one million sets of PTN equipment, how to make the current network PTN devices are fully utilized, this is the issue of China Mobile focus.

After the fiber splicing, the light transmitted to the optical fiber splice joints will have a certain amount of loss, called splice loss. Optical fiber splice loss is mainly composed of an optical fiber transmission loss and splice loss itself constituted. As the quality of fiber optic splice fiber-optic lines will result in transmission loss, optical line transmission distance and other factors, therefore, to minimize fiber optic fusion splice loss, in order to ensure the transmission quality of the fiber CATV signals.

1. Optical performance testing, including the return loss / insertion loss testing. Test instruments selectable FibKey 7602 Return Loss / Insertion Loss integration testing equipment.

According to the building fire rating and fire-resistant material requirements, cabling system should take appropriate measures. In flammable region and shafts in the building wiring should be used flame retardant cable or fiber optic cable; in large public places should adopt flame retardant, low smoke, low toxicity cable or fiber optic cable; between adjacent equipment room or the transfer should be used flame retardant wiring devices.

Fiber Jumper products are widely applied to: the communications room, fiber to the home, local area networks, fiber optic sensors, fiber optic communication systems, fiber optic transmission equipment connected, defense readiness and so on. It applies to cable television, telecommunications networks, computer networks and fiber optical test equipment. Broken down mainly used in several ways.