OM5 vs OM4 fiber optic

OM4 and OM5 are both 50 µm multimode fibers, but OM5 supports a wider wavelength range for SWDM applications, while OM4 is optimized for standard 850 nm transmission.

Core and Bandwidth

Both OM4 and OM5 fibers have a 50 µm core diameter and are designed for high-speed data transmission in data centers and enterprise networks. OM4 has a modal bandwidth of 4700 MHz·km at 850 nm, optimized for standard 10G, 40G, and 100G Ethernet links. OM5 maintains the same 850 nm bandwidth but adds support for 2470 MHz·km at 953 nm, enabling multiple wavelengths to be transmitted simultaneously using Short Wave Division Multiplexing (SWDM) .

Wavelength and Multiplexing

• OM4: Optimized for a single wavelength, typically 850 nm, suitable for standard VCSEL-based transceivers .
• OM5: Known as Wideband Multimode Fiber (WBMMF), it supports a wavelength range from 850 nm to 953 nm, allowing four different wavelengths to travel simultaneously on the same fiber strand without interference, which is essential for SWDM applications [5^].

Transmission Distances

For standard Ethernet applications at 850 nm, OM4 and OM5 offer similar distances:

• 10G Ethernet: up to 400–550 meters
• 40G/100G Ethernet: up to 150 meters OM5 does not extend distance for standard single-wavelength transceivers; its advantage is only realized when using SWDM transceivers .

Jacket Color and Identification

• OM4: Typically has an aqua-colored jacket for easy identification .
• OM5: Uses a lime green jacket to distinguish it from OM4 and other multimode fibers .

Applications and Cost Considerations

• OM4: Ideal for current high-speed networks using standard 10G, 25G, 40G, and 100G transceivers. It is cost-effective and widely deployed .
• OM5: Recommended for future-proofing networks that plan to use SWDM4 or BiDi transceivers, supporting multiple wavelengths for higher aggregate bandwidth. OM5 is more expensive and offers no performance gain for standard 850 nm transceivers .

Summary

In conclusion, choose OM4 for standard high-speed Ethernet deployments and OM5 only if you plan to implement SWDM technology to leverage multiple wavelengths on a single fiber strand .