Differences Between Single-mode & Multi-mode Transceiver
Nowadays, virtualization and cloud consolidation have placed higher bandwidth demands on data center networks, pushing the need to deploy new fiber links that can deliver greater bandwidth and improved power efficiency. During the years, fiber optical technology has stepped forward with constant development and improvement to be maturer and maturer, and now comes as the ideal solution for higher-speed and higher-performance data transmission, during which data is received by fiber optic transceivers through fiber cables.
With the furious competition in telecommunication market, a wide selection of fiber optic transceivers has been designed and provided for networking use. It’s known that when selecting fiber optic transceivers, several factor need to be considered: form-factor, package, fiber type, etc. Here, in this text, detailed information goes to the third one—fiber type, that is single-mode transceiver and multi-mode transceiver. What are the differences between them? Have any idea? Follow this article and get answers.
Single-mode transceiver, as its name shows, works on single -mode fiber (SMF), while multi-mode transceiver operates over multi-mode fiber (MMF).
Compared with MMF, SMF has much tighter tolerances for optics used. The SMF core is smaller and the laser wavelength is narrower., meaning that SMF has the capability for higher bandwidth and much longer distances in transmission. Single-mode transceivers work mainly in 1310nm and 1550nm wavelengths, mostly used in long distance transmission environment, with reaching distances ranging from 2km, to 10km, to 40km, to 60km, to 80km and or even to 120km. 1000BASE-LX and 10GBASE-LR (eg. JD094B) are commonly used single-mode transceiver types.
Generally speaking, single-mode transceivers use the following color coding:
- Violet color coded bale clasp designates the 1490nm transceiver;
- Blue color coded bale clasp designates the 1510nm transceiver;
- Yellow color coded bale clasp designates the 1550nm transceiver;
The color of the compatible fiber optic patch cord or pigtail is yellow.
With a much bigger core, MMF usually uses a longer wavelength of light. Because of this, the optics used in MMF have a higher capability to gather light from the laser. In practical terms, this means that the optics are cheaper. The common multi-mode transceivers operate in 850nm wavelength and are only used for short distance transmission, reaching 100m and 500m. Among these multi-mode transceiver types, including 1000BASE-SX, 10GBASE-SR and 10GBASE-LRM, 1000BASE-SX SFP transceivers are a commonplace in Gigabit Ethernet (GbE) applications. Take SFP-GE-S for example, this Cisco compatible 1000BASE-SX SFP listed in Fiberstore is able to achieve 550m over OM2 MMF using 850nm wavelength laser.
Only black color coded bale clasp is used in multi-mode transceivers. The color of the compatible fiber optic patch cord or pigtail is orange.
When we use single-mode and multi-mode transceivers, we should keep the following points in mind.
- Make sure that the transceivers in both ends of the fiber patch cord are of the same wavelength. A simple way to do it is to ensure that the color of the modules is consistent.
- No bends or winding of fiber optic cables, so as to avoid the increase of the attenuation in data transmission.
- Generally speaking, short-wave transceiver modules use with multi-mode fibers (ie. orange fiber patch cord), while long-wave SFP modules use with single-mode fiber (ie. yellow fiber patch cord). As such, the accurate data transmission is assured.
- If transceiver module isn’t in use, be sure to cover the empty port with a dust plug to protect the optical bore.
When choosing a transceiver module for your fiber link, it’s necessary to make sure the transmission distance, and fiber type, then you can select the right transceiver module more efficiently. Certainly, cost in most cases, becomes a budget pressure to many users. To save money, compatible modules provided at lower prices but with the same quality and reliability are the ideal choices. Fiberstore, as a professional fiber optical product supplier, offers 100% compatible fiber optic transceiver modules of many brands, like the above-mentioned HP JD094B and Cisco SFP-GE-S. For more information about fiber optic transceiver modules, you can visit Fiberstore or connect me at Linkedin @Fern Xu (Fiberstore).