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.

Recently, ZTE and Telefonica officially signed a global cooperation agreement to further become the main technology partner Telefonica.

T-MPLS (Transport MPLS) is a connection-oriented packet transport technology. In the transport network, the client signal is mapped into the MPLS frame and use MPLS mechanisms (such as label switching, the label stack) forwards, while it increases the basic functions of the transport layer, such as connectivity and performance monitoring, survivability (protection and restoration), management and control plane (ASON/GMPLS).

Narrowband PON network topology and the same ATM-PON, which has the following major differences between ATM-PON:
◆ ATM-PON broadband access technology, can provide users with more than 2Mb/s access rate; narrowband access technology only supports narrowband service, to provide users with access speed of up to 2Mb/s.

The most important feature of ATM-PON, is its passive multipoint type network structure. It combines the ATM technology and passive optical network technology to provide a variety of services from existing narrowband to broadband. ATM-PON by the OLT, ONU / ONT and passive optical splitter components.

Active optical network central office equipment (CE) and remote equipment (RE) connected via active optical transmission equipment. Transmission technology is the backbone network SDH and PDH technologies have been widely adopted, but the main SDH technology. Remote device mainly to complete the collection business, interface adapter, multiplexing and transmission. Central office equipment mainly to complete the interface adapter, multiplexing and transmission. In addition, the central office equipment to the network element management system also provides network management interface. In the actual construction of the access network, active optical network topology is typically star or ring. Active optical network technology has the following characteristics:

OTN's intelligent optical network will provide the ideal solution for the transmission of large-granule broadband services. Inter provincial transport network main trunk transport network, provincial trunk transport network, metro (local) transport network structure, while the Metro (local) transport network can be further divided into the core layer, convergence layer and access layer. SDH relative terms, the biggest advantage of OTN technology is to provide scheduling and delivery of large particles of bandwidth, therefore, at different levels whether to adopt OTN network technology, depending on the size of the primary particles dispatch service bandwidth. According to the network situation, primarily particles inter-provincial trunk transmission network, the province trunk transport network and metropolitan area (local) transport network core layer of scheduling is generally Gb / s and above, therefore, these levels can be given priority and scalability advantages OTN technology to build better. For Metro (local) transport network convergence and access layer, when major scheduling particles reach Gb / s order of priority can also be constructed using OTN technology.

DWDM is an optical fiber communication transmission technology, it is the use of an optical fiber can simultaneously transmit a plurality of different wavelengths of light characteristic wavelength range into the fiber may be applied to a number of bands, each band used a separate channel to transmit a predetermined wavelength of the optical signal technology.