We’ve spoken frequently in the past about the difference between single mode and multimode fiber. Multimode fiber can also be divided into 5 grades: OM1, OM2, OM3, OM4, and now OM5.

How Many Types of Multimode Fiber?

Multimode fiber offers five different types of cabling which are OM1, OM2, OM3, OM4, OM5 fibers.

OM1 Fiber. OM1 fiber typically comes with an orange jacket and have a core size of 62.5 µm. It can support 10 Gigabit Ethernet at lengths of up to 33 meters. It is most commonly used for 100 Megabit Ethernet applications. This type commonly uses a LED light source.

OM1 Fiber, Orange Outer Sheath

OM2 Fiber. Likewise, OM2 fiber also comes with an orange jacket and uses a LED light source but with a smaller core size of 50 µm. It supports up to 10 Gigabit Ethernet at lengths up to 82 meters but is more commonly used for 1 Gigabit Ethernet applications.

OM2 Fiber, Orange Outer Sheath

OM3 Fiber. OM3 fiber comes with an aqua color jacket. Like the OM2, its core size is 50 µm, but the cable is optimized for laser-based equipment. OM3 supports 10 Gigabit Ethernet at lengths up to 300 meters. Besides, OM3 is able to support 40 Gigabit and 100 Gigabit Ethernet up to 100 meters, however, 10 Gigabit Ethernet is most commonly used.

OM3 Fiber, Aqua Blue Outer Sheath

OM4 Fiber. OM4 fiber is completely backwards compatible with OM3 fiber and its outer sheath is aqua blue or violet. OM4 was developed specifically for VSCEL laser transmission and allows 10 Gig/s link distances of up to 550m compared to 300M with OM3. And it’s able to run 40/100GB up to 150 meters utilizing a MPO connector.

OM4 Fiber, Aqua Blue or Violet Outer Sheath

OM5 Fiber. OM5 fiber is the newest type of multimode fiber, and it is backwards compatible with OM4. It has the same core size as OM2, OM3, and OM4. The color of OM5 fiber jacket was chosen as water green. It is designed and specified to support at least four WDM channels at a minimum speed of 28Gbps per channel through the 850-953 nm window.

OM5 Fiber, Water Green Outer Sheath

What’s the Difference between Multimode Fibers?

Physical Difference. Physical difference mainly lies in diameter, jacket color, optical source and bandwidth.