Fiber Optic Cable

Smooth Migration to 40/100GbE with OM3 and OM4

The continued requirement for expansion and scalability in the data center drives the migration to 40/100GbE. In the process of upgrading to higher-bandwidth data center, cable deployment plays an important part. The fiber optic cable used in data center should provide reliable performance not only for current but also for future applications. OM3 and OM4 were available as the future-proof cabling for 40/100 Gigabit Ethernet network. Today, we are going to introduce these two types of cable in details.

Multimode Fiber Cable – OM3 and OM4

As we all know, multimode fiber is often categorized into four types—OM1, OM2, OM3 and OM4. OM3 and OM4 are laser-optimized, high-bandwidth 50 micron multimode fiber cables, which are designed to enhance the system cost benefits enabled by 850nm vertical cavity surface emitting lasers (VCSELs) for existing 1G and 10G applications as well as future 40G and 100G applications. The following image shows OM3 and OM4.


Advantages of OM3 and OM4

As increasing bandwidth requirements are called out in new installations, particularly 40 and 100GbE standards, transmission distances over fiber optic cables contained in existing infrastructure may become increasingly limited. And these higher bandwidth system requirements have dictated a need to transition from cost-effective multimode systems to more costly single-mode systems. Until OM3 and OM4 was formally specified, many next-generation 40/100GbE applications would have had to make the leap to single-mode system solutions. OM3 and OM4 provides many advantages that helps the smooth migration to 40/100GbE.

High Bandwidth: Bandwidth is the first reason why OM3 and OM4 are preferable. OM3 and OM4 are optimized for 850nm transmission and have a minimum 2000 MHz•km and 4700 MHz•km effective modal bandwidth(EMB) respectively, while OM1 and OM2 with maximum 500 MHz•km as we can seen in the following table. It is obvious that with OM3 and OM4, the optical infrastructure deployed in the data center will meet the performance criteria set forth by IEEE for bandwidth.

bandwidth and transmission distance of OM3 and OM4

Long Transmission Distance: The transmission distance of fiber optic cables will influence the data center cabling. Compared to traditional multimode fiber, OM3 and OM4 can support longer transmission distance. Generally, OM3 can run 40/100Gbps at 100 meters and OM4 can support the link length up to 150 meters at the data rate of 40/100Gbps.

Low Insertion Loss: Insertion loss has always been an important factor that technically should consider during the data center cabling. The lower the insertion loss, the better the performance. According to the 40/100G standard, OM3 is specified to a 100m distance with a maximum channel loss of 1.9dB, and OM4 is specified to a 150m distance with a maximum channel loss of 1.5 dB, including a total connector loss budget of 1.0 dB as we can seen from the table below.

insertion loss of OM3 and OM4

Cost Saving: Budget is always the most vital factor that should be taken into consideration when setting up data center. As we have mentioned above, when upgrading to higher bandwidth network previously, many IT managers will choose costly single-mode fiber to achieve connections, but with the appearance of and OM4, the cost used in the migration to 40/100GbE will greatly reduce.

With OM3, Why We Still Need OM4?

Actually, OM3 has the similar performance as OM4 from the four aspects that we have discussed above, but with OM3, why we still need OM4?

It is important to note that OM4 is not necessarily designed to be a replacement for OM3. For most systems, OM3 is sufficient to cover the bandwidth needs at the distances of the current installation base. Most system requirements can still be reliably and cost-effectively achieved with OM3. The primary benefit that OM4 provides is additional reach at extended bandwidth at an overall cost still less than that of an OS2 single-mode system. In other words, OM4 provides a solution that allows more installations to avoid the significantly higher costs of single-mode systems. Additionally, OM4 provides an opportunity to future-proof cabling infrastructure. OM4 is completely backward-compatible with existing OM3 systems. The additional bandwidth and lower attenuation of OM4 offer additional insertion loss margin. As a result, users of OM4 gain additional safety margin to help compensate for less-than-ideal cabling installations as well as provide margin for degradation due to moves, adds, and changes over the life of the installation.


As the ever-increasing need for higher-speed transmission, upgrading to 40/100GbE is underway. OM3 and OM4, as future-proof cabling, play an important role in the smooth migration to higher bandwidth networks. FS.COM provides a range of OM3 and OM4 in different types according to your requirements, and we devote to offer the most affordable fiber optic cable price for customers.

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