Optical fiber transceivers can easily integrate copper-based cabling systems into fiber optic cabling systems, with strong flexibility and high cost performance. Typically, they can convert electrical signals into optical signals (and vice versa) to extend transmission distances. So, how to use fiber optic transceivers in the network and properly connect them to network equipment such as switches, optical modules, etc.? This article will detail it for you.
How to use fiber optic transceivers?
Today, fiber optic transceivers have been widely used in various industries, including security monitoring, enterprise networks, campus LANs, etc. Optical transceivers are small and take up little space, so they are ideal for deployment in wiring closets, enclosures, etc. where space is limited. Although the application environments of fiber optic transceivers are different, the connection methods are essentially the same. The following describes the common connection methods of fiber optic transceivers.
Typically, fiber optic transceivers are used in pairs in a network, but sometimes they are used individually to connect copper cabling to fiber optic equipment. As shown in the figure below, a fiber optic transceiver with 1 SFP port and 1 RJ45 port is used to connect two Ethernet switches. The SFP port on the fiber optic transceiver is used to connect with the SFP port on switch A. , the RJ45 port is used to connect with the electrical port on switch B. The connection method is as follows:
1. Use a UTP cable (network cable above Cat5) to connect the RJ45 port of switch B to the optical cable.
connected to the electrical port on the fiber transceiver.
2. Insert the SFP optical module into the SFP port on the optical transceiver, and then insert the other SFP optical module
The module is inserted into the SFP port of switch A.
3. Insert the optical fiber jumper into the optical transceiver and the SFP optical module on switch A.
A pair of fiber optic transceivers are usually used to connect two copper cabling-based network devices together to extend the transmission distance. This is also a common scenario for using fiber optic transceivers in the network. The steps on how to use a pair of fiber optic transceivers with network switches, optical modules, fiber patch cords and copper cables are as follows:
1. Use a UTP cable (network cable above Cat5) to connect the electrical port of switch A to the optical fiber on the left.
connected to the RJ45 port of the transmitter.
2. Insert one SFP optical module into the SFP port of the left optical transceiver, and then insert the other
The SFP optical module is inserted into the SFP port of the optical transceiver on the right.
3. Use a fiber jumper to connect the two fiber optic transceivers.
4. Use a UTP cable to connect the RJ45 port of the optical transceiver on the right to the electrical port of switch B.
Note: Most optical modules are hot-swappable, so there is no need to power down the optical transceiver when inserting the optical module into the corresponding port. However, it should be noted that when removing the optical module, the fiber jumper needs to be removed first; the fiber jumper is inserted after the optical module is inserted into the optical transceiver.
Precautions for using fiber optic transceivers
Optical transceivers are plug-and-play devices, and there are still some factors to consider when connecting them to other network equipment. It is best to choose a flat, safe location to deploy the fiber optic transceiver, and also need to leave some space around the fiber optic transceiver for ventilation.
The wavelengths of the optical modules inserted into the optical transceivers should be the same. That is to say, if the wavelength of the optical module on one end of the optical fiber transceiver is 1310nm or 850nm, the wavelength of the optical module on the other end of the optical fiber transceiver should also be the same. At the same time, the speed of the optical transceiver and the optical module must also be the same: the gigabit optical module must be used together with the gigabit optical transceiver. In addition to this, the type of optical modules on the fiber optic transceivers used in pairs should also be the same.
The jumper inserted into the fiber optic transceiver needs to match the port of the fiber optic transceiver. Usually, the SC fiber optic jumper is used to connect the fiber optic transceiver to the SC port, while the LC fiber optic jumper needs to be inserted into the SFP/ SFP+ ports.
It is necessary to confirm whether the fiber optic transceiver supports full-duplex or half-duplex transmission. If a fiber optic transceiver that supports full-duplex is connected to a switch or hub that supports half-duplex mode, it will cause serious packet loss.
The operating temperature of the fiber optic transceiver needs to be kept within an appropriate range, otherwise the fiber optic transceiver will not work. The parameters may vary for different suppliers of fiber optic transceivers.
How to troubleshoot and solve fiber optic transceiver faults?
The use of fiber optic transceivers is very simple. When the fiber optic transceivers are applied to the network, if they do not work normally, troubleshooting is required, which can be eliminated and solved from the following six aspects:
1. The power indicator light is off, and the optical transceiver cannot communicate.
Verify that the power cord is connected to the power connector on the back of the fiber optic transceiver.
Connect other devices to an electrical outlet and check that the electrical outlet has power.
Try another power adapter of the same type that matches the fiber optic transceiver.
Check that the voltage of the power supply is within the normal range.
2. The SYS indicator on the optical transceiver does not light up.
Typically, an unlit SYS light on a fiber optic transceiver indicates that internal components on the device are damaged or not functioning properly. You can try restarting the device. If the power supply is not working, please contact your supplier for assistance.
3. The SYS indicator on the optical transceiver keeps flashing.
An error has occurred on the machine. You can try restarting the device. If that doesn’t work, remove and reinstall the SFP optical module, or try a replacement SFP optical module. Or check whether the SFP optical module matches the optical transceiver.
4. The network between the RJ45 port on the optical transceiver and the terminal device is slow.
There may be a duplex mode mismatch between the fiber optic transceiver port and the end device port. This happens when an auto-negotiated RJ45 port is used to connect to a device whose fixed duplex mode is full duplex. In this case, simply adjust the duplex mode on the end device port and the fiber optic transceiver port so that both ports use the same duplex mode.
5. There is no communication between the equipment connected to the fiber optic transceiver.
The TX and RX ends of the fiber jumper are reversed, or the RJ45 port is not connected to the correct port on the device (please pay attention to the connection method of the straight-through cable and the crossover cable).
6. On and off phenomenon
It may be that the attenuation of the optical path is too large. At this time, an optical power meter can be used to measure the optical power of the receiving end. If it is near the receiving sensitivity range, it can be basically judged that the optical path is faulty within the range of 1-2dB.
It may be that the switch connected to the optical transceiver is faulty. At this time, replace the switch with a PC, that is, the two optical transceivers are directly connected to the PC, and the two ends are pinged.
It may be the failure of the fiber optic transceiver. At this time, you can connect both ends of the fiber optic transceiver to the PC (not through the switch). After the two ends have no problem with PING, transfer a large file (100M) or more from one end to the other, and observe it. If the speed is very slow (files below 200M are transmitted for more than 15 minutes), it can be basically judged that the optical fiber transceiver is faulty.
Optical transceivers can be flexibly deployed in different network environments, but their connection methods are basically the same. The above connection methods, precautions and solutions to common faults are just a reference for how to use fiber optic transceivers in your network. If there is an unsolvable fault, please contact your supplier for professional technical support.
Post time: Mar-17-2022