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Fiber Type Versus Speed and Distance

In this video we will discuss the different types of fiber optic cable and their connection to speed and distance. This information will help you chose the right fiber optic cable based on your present and future needs. Fiber optic strands are made up of two main components consisting of the core and the cladding. The function of the core is to transmit the light, whereas the claddings function is to reflect the light and keep it contained within and to propagate the light through the fiber. What do the fiber terms 62.5/125, 50/125, and 9/125 refer to? These terms refer to the diameter of microns of a fiber optic cable's core and cladding. Together, they are roughly the diameter of a human hair. The Multimode core sizes come in different classifications: OM1, OM2, OM3, OM4, and OM5. OM1 or 62.5/125 Fiber is the largest fiber core, therefore the light has more time to bounce around or reflect, and it takes longer for it to reach the end point. OM1 Fiber supports 1 Gigabit Ethernet to 275 meters and can support 10 Gigabit Ethernet up to 33 meters. As you can see, OM1 fiber is not the best choice for a 10 Gig network as it has the lowest data carrying capacity and shortest distance limitations. OM2 Fiber is in the 50/125 classification but is more in line with OM1 fiber in terms of speed and distance. OM2 fiber can support 1 Gigabit ethernet up to 550 meters but can only support 10 Gigabit Ethernet up to 82 meters. With the advance of OM3 fiber, OM2 has become essential phased out in the industry. OM3 is usually just referred to as 10 Gig since it's generally the best choice for 10 Gigabyte Ethernet multimode fiber. OM3 was designed specifically for that purpose. bOM3 fiber can support 1 Gigabit ethernet up to 550 meters and can support 10 Gigabit Ethernet up to 300 meters. In addition, it can also support 40 Gig up to 100 meters, and 100 Gig up to 70 meters. OM4 fiber is backwards compatible with OM3 fiber and was developed for VCSEL laser transmission. OM4 fiber can support 10 Gigabit ethernet up to 550 meters and it can also support 40 and 100 Gig up to 150 meters. OM5 fiber also known as SWDM or Shortwave Wavelength-division multiplexing fiber is downwards compatible with OM4 fiber and has the ability to use four wavelengths across the 850 to 950 nm range. But for comparative purposes as a single signal, OM5 fiber can support 10 Gigabit ethernet up to 550 meters and it can also support 40 and 100 Gig up to 150 meters. Singlemode fiber has the smallest fiber core, and therefore there is less room for the light to reflect and has less attenuation. Singlemode fiber can transmit light at much longer distances, but OM3/OM4/ and OM5 multimode fiber supports a higher data rates. Singlemode fiber can support 1 Gigabit ethernet up to 5 kilometers and it can also support 10 Gigabit ethernet up to 10 kilometers. As we can see, the fiber type and the distance of the run all play an important factor in the overall speed. But one important thing to note is that you will only be as fast as your weakest link. However, future proofing your network is always a good idea so when all the other factors become a possibility, your fiber backbone will be ready.