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.

Optical communication technology in the 2015 forum held recently, Ovum analyst Daryl Inniss speech, analyze the optical communication opportunities in the data center field. He said the data center network is driving demand for high-bandwidth connections between data centers and data center for internal. Terabit-level connection between the data center needs; and internal data centers require more cost connection to 100G. However, the high cost of optical networks market slowdown in the rate of expansion is a fundamental problem.

(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.

Recently, ZTE was awarded the SDN OpenFlow 1.3 ONF conformance testing certification, becoming the first manufacturer to receive this certification. ZTE Bearer Network Products M6000-S in the test performance, stability, and other vendors controllers successfully docking site, excellent test results.

For carriers, SDN, NFV and Cloud has become the ICT transformation keywords. And in order to "separate data and control, software and hardware decoupling" is characterized by SDN already determined the status to the next generation network architecture evolution direction. China Telecom Group, Wei Leping CST has pointed out, SDN open network IT process, is an important breakthrough in the direction to telecommunications technology, as well as IT and software business breakthroughs channel telecommunication barriers, suggesting a large adjustment of industrial structure pattern.

Open Networking Foundation (ONF) Executive Chairman Dan Pitt in September 8, 2015 ONF Member Workday officially announced, Huawei, ZTE, H3C, Digital Network (DCN) and other four companies formally through five SDN switch by the BII - OpenFlow v1.3 conformance certification testing center for testing and certification of global SDN, becoming the world's first through OpenFlow v1.3 protocol conformance certified equipment.

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.