Tag Archives: 40/100G

The Basics of OM4 Multimode Fibers

As the demand for bandwidth in enterprise applications such as data centers continues to boom, new transmission media must be developed continually to meet end user requirements. With next-generation 40 and 100 Gigabit Ethernet speeds on the horizon, the industry is developing a new type of multimode fiber called OM4. What is it? Why is it able to meet the high data rate requirements? Here is what you need to know about OM4 multimode fibers.

What Is OM4 Fiber?

Two standards define the use of OM4 fiber in high-speed networks: TIA document TIA-492AAAD, which contains the OM4 fiber performance specifications; and the IEC 60793-2-10 international standard, which provides equivalent OM4 specifications under fiber type A1a.3. OM4 multi-mode fiber has a core of 50 microns, but the fiber is optimized for laser based equipment that uses fewer modes of light. It is designed to enhance the system cost benefits enabled by 850 nm VCSELs (vertical cavity surface emitting lasers) for existing 1Gbps and 10Gbps applications as well as future 40Gbps and 100Gbps systems. OM4 fiber will support Ethernet, Fibre Channel, and OIF applications, allowing extended reach upwards of 550 meters at 10Gbps for ultra long building backbones and medium length campus backbones. With an Effective Modal Bandwidth (EMB, also known as laser bandwidth) of 4700 MHz-km(more than double the IEEE requirement for 10Gbps 300 meter support), OM4 fiber is also especially well suited for shorter reach data center and high performance computing applications. It is important to note that OM4 glass is not necessarily designed to be a replacement for OM3. Despite the relatively long-standing availability of OM4, there are no plans to obsolete OM3 fiber optic cabling.


Advantages of OM4 Fiber

OM4 provides an opportunity to future-proof cabling infrastructure. OM4 is completely backwards-compatible with existing OM3 systems. As a result, these two grades of glass are interchangeable within the transmission distance limitations. The additional bandwidth and lower attenuation of OM4 provide 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.

OM4 Fiber Patch Cable

OM4 is the latest high modal bandwidth high performance 50/125 Graded Index Multimode (GIMM) cabled fibre specification. OM4 fiber enables extended range performance over high bit rate links such as 8 Gigabit Fiber Channel and 10 Gigabit Ethernet compared to existing fibre types. OM4 fiber patch cable can be regarded as improvement on the existed OM3 standards. Its assemblies are ready to meet the requirement for future 40G and 100G fiber optic networks, there are simplex and duplex OM4 multimode fiber patch cord types. OM4 multimode fiber patch cable are terminated with different fiber optic connectors, like LC, SC, ST, FC, MTRJ, MU, and E2000. These cables can be simplex or duplex and customized in optional lengths.


The demand for the development of network transmission requires that optical fiber can support future 40Gbit/s and 100Gbit/s transmission. OM4 fiber provides next generation multimode fiber performance for today and tomorrow’s high speed applications. With its significantly higher bandwidth, network designers and operators can be assured that fiber patch cord will continue to provide the most cost effective solutions for short reach applications in data centers and LANs. Laser-optimized multi-mode fiber OM4 takes advantage of 850 nm VCSEL laser technology to reduce the overall cost, provide you with higher bandwidth choices.