Optical fiber transceivers are generally used in actual network environments where Ethernet cables cannot be covered and optical fibers must be used to extend the transmission distance. At the same time, they have also played a huge role in helping to connect the last mile of optical fiber lines to metropolitan area networks and outer networks. The role of.
Single-mode optical fiber transceiver: transmission distance of 20 kilometers to 120 kilometers Multi-mode optical fiber transceiver: transmission distance of 2 kilometers to 5 kilometers For example, the transmit power of a 5km fiber optic transceiver is generally between -20 and -14db, and the receiving sensitivity is -30db, using a wavelength of 1310nm; while the transmit power of a 120km fiber optic transceiver is mostly between -5 and 0dB, and the receiving sensitivity is It is -38dB, and a wavelength of 1550nm is used
Single-fiber optical fiber transceiver: the data received and sent are transmitted on a fiber Dual-fiber optical fiber transceiver: the data received and sent are transmitted on a pair of optical fibers As the name implies, single-fiber equipment can save half of the optical fiber, that is, to receive and send data on one optical fiber, which is very suitable for places where optical fiber resources are tight. This type of product uses wavelength division multiplexing technology, and the wavelengths used are mostly 1310nm and 1550nm. However, because there is no unified international standard for single-fiber transceiver products, there may be incompatibility between products of different manufacturers when they are interconnected. In addition, due to the use of wavelength division multiplexing, single-fiber transceiver products generally have the characteristic of large signal attenuation.
Working level/rate
100M Ethernet fiber optic transceiver: working at the physical layer 10/100M adaptive Ethernet fiber optic transceiver: working at the data link layer According to the working level/rate, it can be divided into single 10M, 100M fiber optic transceivers, 10/100M adaptive fiber optic transceivers, 1000M fiber optic transceivers, and 10/100/1000 adaptive transceivers. Among them, the single 10M and 100M transceiver products work at the physical layer, and the transceiver products working at this layer forward data bit by bit. This forwarding method has the advantages of fast forwarding speed, high transparency rate, and low delay. It is suitable for use on fixed-rate links. At the same time, since such devices do not have an auto-negotiation process before normal communication, they are compatible Doing better in terms of sex and stability.
Fiber optic transceiver classification: structure classification
Desktop (stand-alone) fiber optic transceiver: stand-alone client equipment Rack-mounted (modular) optical fiber transceiver: installed in a sixteen-slot chassis, using centralized power supply According to the structure, it can be divided into desktop (stand-alone) fiber optic transceivers and rack-mounted fiber optic transceivers. The desktop optical fiber transceiver is suitable for a single user, such as meeting the uplink of a single switch in the corridor. Rack-mounted (modular) fiber optic transceivers are suitable for the aggregation of multiple users. At present, most domestic racks are 16-slot products, that is, up to 16 modular fiber optic transceivers can be inserted in a rack.
Fiber optic transceiver classification: management type classification
Unmanaged Ethernet optical fiber transceiver: plug and play, set the electrical port working mode through the hardware dial switch Network management type Ethernet fiber optic transceiver: support carrier-grade network management
Optical fiber transceiver classification: network management classification
It can be divided into unmanaged fiber optic transceivers and network managed fiber optic transceivers. Most operators hope that all devices in their networks can be remotely managed. Fiber optic transceiver products, like switches and routers, are gradually developing in this direction. The fiber optic transceivers that can be networked can also be subdivided into central office network management and user terminal network management. The fiber optic transceivers that can be managed by the central office are mainly rack-mounted products, and most of them adopt a master-slave management structure. On the one hand, the master network management module needs to poll the network management information on its own rack, and on the other hand, it also needs to collect all the slave sub-racks. The information on the network is then aggregated and submitted to the network management server. For example, the OL200 series of network-managed optical fiber transceiver products provided by Wuhan Fiberhome Networks supports a network management structure of 1 (master) + 9 (slave), and can manage up to 150 optical fiber transceivers at a time. The user-side network management can be divided into three main methods: the first is to run a specific protocol between the central office and the client device. The protocol is responsible for sending the status information of the client to the central office, and the CPU of the central office device handles these states. Information and submit it to the network management server; the second is that the optical fiber transceiver of the central office can detect the optical power on the optical port, so when there is a problem on the optical path, the optical power can be used to determine whether the problem is on the optical fiber or the failure of the user equipment ; The third is to install the main control CPU on the fiber transceiver on the user side, so that the network management system can monitor the working status of the user side equipment on the one hand, and can also realize remote configuration and remote restart. Among these three client-side network management methods, the first two are strictly for remote monitoring of client-side equipment, while the third is the real remote network management. However, since the third method adds a CPU on the user side, which also increases the cost of the user side equipment, the first two methods have more advantages in terms of price. As operators demand more and more equipment network management, it is believed that the network management of fiber optic transceivers will become more practical and intelligent.
Fiber optic transceiver classification: power supply classification
Built-in power supply fiber optic transceiver: the built-in switching power supply is a carrier-grade power supply; external power supply fiber optic transceiver: the external transformer power supply is mostly used in civilian equipment.
Fiber optic transceiver classification: working method classification
The full-duplex mode means that when the sending and receiving of data are split and transmitted by two different transmission lines, both parties in the communication can send and receive at the same time. Such a transmission mode is a full-duplex system. In the full-duplex mode, each end of the communication system is equipped with a transmitter and a receiver, so data can be controlled to be transmitted in both directions at the same time. The full-duplex mode does not need to switch the direction, so there is no time delay caused by the switching operation. The half-duplex mode refers to the use of the same transmission line for both receiving and sending. Although data can be transmitted in both directions, the two parties cannot send and receive data at the same time. This transmission mode is half-duplex. When the half-duplex mode is adopted, the transmitter and receiver at each end of the communication system are transferred to the communication line through the receiving/sending switch to switch the direction. Therefore, time delay will occur.