Understanding Fiber Cable Types: OM1 vs OM2 vs OM3 vs OM4

Quick Definition: OM3 and OM4 are the current multi-mode fiber types of choice when it comes to high bandwidth long-distance network connections, while OM1 and OM2 are outdated versions. Which one you should use comes down to your network requirements, how future-proof you want your network to be, and the budget available.

In today’s fast-paced, high-bandwidth, always-online world, data must literally move at the speed of light to keep up with our ever-growing need for bandwidth. This requires the technology that has become the literal backbone of the internet: fiber optic cabling. Fiber transmits data via light through glass, offering speeds and bandwidths that blow copper out of the water.

We’ve recently discussed two different types of fiber cables, single-mode and multi-mode. However, the rabbit hole goes deeper, as there are subtypes of multi-mode fiber to investigate. Today, we will delve into the separate types of multi-mode fiber cables: OM1, OM2, OM3, and OM4. We’ll look at the advantages and applications of each to help you make an informed decision that meets your networking needs.

What are OM1 and OM2 Fiber Optic Cables?

Before we look at the two current standards for multi-mode fiber (OM3 and OM4), it’s important to investigate the origins of fiber optic cables. OM1 and OM2 were standard fare in the 1990s and 2000s, but today they are considered obsolete. They aren’t even listed in the ISO/IEC 11801 and TIA 568 wiring standards.

The reasons for their decline were simple: bandwidth and cable length. OM1 could support 10 Gbps, but only for 33 meters. It was commonly used for shorter 100 Mbps connections. OM2 was slightly better at 10 Gbps for 82 meters but was also only used for shorter runs up to 1 Gbps. Why even mention OM1 and OM2, then?

Because you still might see them out in the wild in older installations. The telltale sign is the cable jacket, the outer coating of a cable that protects the delicate fiber inside of it. OM1 and OM2 always have an orange jacket (versus aqua for OM3 and OM4). Older installations also might require you to change plans to maintain backward compatibility, so it’s worth knowing about OM1 and OM2.

What is OM3 Fiber Optic Cable?

OM3 fiber is very physically similar to OM2; however, OM3’s higher-quality core material allows for better light propagation characteristics throughout the length of the cable. This reduces the model dispersion. This is when different light patterns in the multi-mode fiber arrive at the other end of the cable at different times, reducing the effectiveness of the cable across a longer distance. The core material and more advanced manufacturing techniques required to produce it increase the price, however. On average, OM3 is about twice the price of OM2.

Advantages and Applications of OM3 Cables

OM3’s improvements allow for some distinct advantages over OM1 and OM2. OM3 cables can provide for up to 100 Gbps, a huge bandwidth boost over OM2. OM3 can also run 10 Gbps for 300 meters, an almost 4x improvement over OM2. At 100 Gbps, it is limited to 100 meters.

OM3 cables are found in applications where any combination of speed and distance are essential, including:

• Campus networks: OM3 cables’ improved length allows them to connect buildings across a broader campus. With buildings too far apart for copper to reach, the max length of OM3 is essential.

• Data centers: OM3 cables are commonly used in data centers where high bandwidth connections between servers and connections from servers to storage are paramount for application performance.

• Large wifi deployments: Wifi access points spread across a large area, like a stadium or airport, would require the cable length to reach the spread out access points as well as increased bandwidth to handle large numbers of clients in dense areas.

In these and other applications, OM3 is critical for sufficient data transfer.

What is OM4 Fiber Optic Cable?

OM4 is another step up in performance from OM3. Further improvements in fiber core material and manufacturing allow for another big boost over OM3, but at another doubling in price, on average.

Advantages and Applications of OM4 Cables

OM4 cables provide greater bandwidth than OM3 cables, quadrupling the max speed to a blazing 400 Gbps. OM4 can also run up to 550 meters for 10 Gbps and 125 meters for 100 and 400 Gbps.

OM4 cables find applications in various scenarios:

• Future-proofing: If it’s within your budget, OM4 is a great choice to install even if you don’t require the bandwidth it provides today. You’ll be ready for future requirements without an expensive reinstall.

• Backbone Installations: OM4 cables are commonly used for backbone installations, feeding multiple locations or buildings from one trunk.

• Anywhere OM3 can be used: Again, if it’s in your budget, OM4 can be used anywhere OM3 would be to provide even greater distance and higher bandwidth connectivity.

OM3 Vs. OM4: Key Differences

Three key factors stand out when choosing between OM3 and OM4: bandwidth, cable length, and cost. OM4 scores the highest in all three: greatest bandwidth over the longest distance but at a greater cost.

For shorter runs, OM3 might be sufficient, like from servers to switches in the same rack, while still maintaining speeds higher than copper. For similar bandwidth needs but at distances greater than 100 meters, OM4 is a better choice. Similarly, shorter but very high bandwidth needs can also be adequately served by OM4 cabling.

Factors to Consider When Choosing Between OM3 and OM4

When making the decision between OM3 and OM4, consider the following factors:

• Network Requirements: Any project starts with gathering requirements. If yours are only for shorter runs, OM3 might be a better, more cost-effective option.

• Future Scalability: Consider also the long-term needs of your network. For higher bandwidth needs in the future, OM4 is a safer bet.

• Budget: If money is already tight, OM3 will get you a better bang for your buck.

To make the right choice, work to balance these three factors to ensure a high-performing network for now and in the future. Fiber is an amazing technology that will power our high-speed networks for years to come, so making an informed choice at the start of your project and your network will serve you well into the future.

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