OADM equipment in long haul and metro networks are useless.
◆ In the trunk applications, OADM device of choice up and down business intermediate nodes.

The main function of OADM is separated from the multi-wavelength channels or insertion of one or more wavelengths, there are fixed and reconfigurable two types.

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:

Optical fiber is a transmission beam subtle and flexible media. Fiber optic cables consist of a bundle of optical fibers, referred to as fiber optic cable. Fiber optic cable for data transmission is the most effective one transmission medium, the advantages of its advantages similar to the optical fiber, mainly in the following areas:

Fiber access can ensure that users with 10Mbps, 100Mbps, 1000Mbps high bandwidth, can be remitted directly connected to the backbone nodes. Mainly applicable to business groups of users and intelligent LAN area, high-speed access to high speed Internet. Available in three specific access to the user.

Active optical access technology Application bandwidth demand, high security communication enterprises and institutions access. It can also be used in the feeder section and wiring section of the access network, and mixed with other access technologies based on the use of wireless or copper wires.

AON (Active Optical Network) is a signal during transmission, the transmission network from the central office equipment to the use of the photoelectric conversion devices, active optoelectronic devices and fiber optic transmission equipment and other active optical fiber between user allocation unit. Active optical device comprises a light source (laser), optical receivers, optical transceivers, optical amplifiers (fiber amplifiers and semiconductor optical amplifiers).