Multimode fiber (MMF) is a kind of optical fiber mostly used in communication over short distance. Multimode fiber optic cable has a larger core, about 50 or 62.5 microns that enables multiple light modes to be propagated. Because of this, more data can pass through the multimode fiber core at a given time.
The maximum transmission distance for MMF cable is around 550m at the speed of 10Git/s. It can transmit farther at lower data rates, such as going about 2km at 100Mb/s. There are several kinds of multimode fiber types available for high-speed network installations, and each with a different reach and data-rate capability. Let us talk about OS2, OM1, OM2, OM3, OM4, OM5.
OS2 (Optical Single-mode 2)
OS2 cables are optimized for long-distance, high-speed data transmission in single-mode fiber networks. They feature a narrow core diameter of 9 microns, which allows for efficient transmission of light over extensive distances with minimal dispersion.
OS2 fibers offer higher bandwidth capabilities, making them suitable for applications such as Gigabit Ethernet and beyond. Due to their low modal dispersion, OS2 cables are commonly used in telecommunications networks, metropolitan area networks (MANs), and long-haul connections where reliable data transmission over extended distances is essential.
OM1 (Optical Multimode 1)
OM1 cables are designed for shorter-distance communication within buildings and campuses, commonly known as multimode fiber networks. With a core diameter of 62.5 microns, OM1 fibers support multiple modes of light propagation over relatively short distances.
While offering lower bandwidth capabilities compared to single-mode fibers, OM1 cables are suitable for Fast Ethernet applications in LANs, data centers, and premises cabling. They are commonly deployed in legacy installations and short-distance scenarios such as horizontal cabling and LAN backbones.
OM2 (Optical Multimode 2)
OM2 cables offer improved performance over OM1 cables for short-distance multimode transmission. With a core diameter of 50 microns, OM2 fibers provide better bandwidth capabilities, making them suitable for Fast Ethernet applications and some Gigabit Ethernet applications.
Optimized for short-distance transmissions, OM2 cables are commonly used in LANs, premises cabling, and other applications where higher bandwidth capabilities are required compared to OM1 cables. Despite exhibiting moderate modal dispersion, OM2 fibers offer enhanced performance for high-speed data transmission over short distances.
OS2 vs OM1 vs OM2
| Basis | OS2 | OM1 | OM2 |
| Fiber Type | Single-mode | Multimode | Multimode |
| Core Diameter | 9 microns | 62.5 microns | 50 microns |
| Bandwidth | Higher (Gigabit and beyond) | Lower (Fast Ethernet) | Higher (Fast Ethernet) |
| Distance | Long distances | Short distances | Short distances |
| Modal Dispersion | Lower | Higher | Moderate |
| Wavelength | 1310 nm (single-mode) | 850 nm (multimode) | 850 nm (multimode) |
| Jacket Color | Yellow | Orange | Orange |
| Applications | Long-distance transmissions, high-speed data networks | Legacy installations, short-distance applications | Short-distance applications |
OM3 (Optical Multimode 3)
OM3 cables are designed for high-speed, short-distance multimode transmission. With a core diameter of 50 microns, OM3 fibers offer improved bandwidth capabilities compared to earlier multimode fibers. They are optimized for medium-distance transmissions and are commonly used in local area networks (LANs), data centers, and premises cabling where higher bandwidth is required.
OM3 cables operate at a wavelength of 850 nm, making them suitable for Gigabit Ethernet and beyond. Despite exhibiting moderate modal dispersion, OM3 fibers provide reliable performance for high-speed data transmission over medium distances.
OM4 (Optical Multimode 4)
OM4 cables build upon the capabilities of OM3 cables, offering even higher bandwidth and performance for short-distance multimode transmission. Like OM3, OM4 fibers have a core diameter of 50 microns and operate at a wavelength of 850 nm.
OM4 fibers feature enhanced optical characteristics, allowing for longer reach and higher data rates compared to OM3 fibers. OM4 cables are commonly deployed in data centers, backbone networks, and other high-performance applications where increased bandwidth and reliability are required.
OM5 (Optical Multimode 5)
OM5 cables represent the latest advancement in multimode fiber technology, designed to support higher data rates and longer distances compared to previous generations of multimode fibers. With a core diameter of 50 microns, OM5 fibers offer increased bandwidth capabilities, making them suitable for emerging high-speed applications such as 40G and 100G Ethernet.
OM5 cables use a wavelength division multiplexing (WDM) technique to enable multiple wavelengths of light to be transmitted simultaneously over the same fiber, allowing for greater scalability and flexibility in network deployments. OM5 fibers are commonly used in data centers, backbone networks, and other environments where high-speed, high-capacity connectivity is essential.
OM3 vs OM4 vs OM5
| Basis | OM3 | OM4 | OM5 |
| Fiber Type | Multimode | Multimode | Multimode |
| Core Diameter | 50 microns | 50 microns | 50 microns |
| Bandwidth | Higher (Gigabit and beyond) | Higher (Gigabit and beyond) | Higher (Gigabit and beyond) |
| Distance | Medium distances | Medium distances | Medium distances |
| Modal Dispersion | Moderate | Moderate | Moderate |
| Wavelength | 850 nm (multimode) | 850 nm (multimode) | 850 nm (multimode) |
| Jacket Color | Aqua | Aqua | Lime Green |
| Applications | Local area networks (LANs), high-speed data networks | Data centers, backbone networks | Data centers, backbone networks |
Generally, OM3, OM4, and OM5 optical fiber cables are optimized for high-speed, short-distance multimode transmission, offering improved bandwidth and performance compared to earlier multimode fibers. Each type of optical fiber cable serves specific applications and requirements, providing network operators with flexibility and scalability in meeting their connectivity needs.