In today’s high-speed data environment, businesses need reliable infrastructure to remain competitive. Fiber optic cables deliver unmatched speed, bandwidth, and security, but choosing the right type for your needs can be challenging.
With 19+ years of experience installing fiber networks across 20,000+ locations, we’ll explain the essential differences between fiber optic cable types so you can make the most informed decision for your business network.
Let’s examine the different optic cable types, their performance capabilities, and optimal applications for commercial environments.
Have a network installation project?
Two Types of Fiber Optic Cable
Fiber optic cables fall into two main categories: single-mode fiber (SMF) and multimode fiber (MMF), each designed for specific transmission requirements.
Single-mode fiber (SMF) features an extremely thin core layer measuring 8-9µm in diameter. This small-diameter core can carry only one light signal (mode). It is ideal for long-distance transmission with minimal signal degradation even when the cable experiences bending or stretching.
Multimode fiber (MMF) has a significantly larger fiber core, typically measuring 50µm or 62.5µm in diameter. This larger core enables MMF to carry multiple light signals simultaneously, delivering high-speed data transmission over shorter distances similar to traditional copper cables.
How Do Fiber Optic Cables Work?
Fiber optic cables consist of two main components:
- Core: Made of glass or plastic, this central channel carries the light signals
- Cladding: Surrounds the core, also made of glass or plastic, but with a lower refractive index
This difference in refractive indices between the glass core and cladding creates total internal reflection, which prevents light from escaping the fiber. This principle enables data to be transmitted at speeds approaching 99.7% of the speed of light. Find out the fiber optic statistics and trends.
What Are the Standard Core Sizes of Optical Fiber Cable?
The core diameter of optical fiber cable is measured in microns (µm):
| Fiber Type | Core Size | Primary Use |
|---|---|---|
| Single mode | 8-9µm | Long-distance networking |
| Multimode | 50µm or 62.5µm | Shorter distances networking |
What Is Single-Mode Fiber?
Single-mode fiber features a thin 8-9µm core that carries a single optical signal. This design significantly reduces signal dispersion (spreading), allowing data to travel much further distances than multimode fiber optic cable, up to 40km or more without signal regeneration for certain applications.
Key benefits of single-mode fiber cable include:
- Lower signal attenuation (0.3-0.5 dB/km)
- Superior distance capability (up to 40+ kilometers)
- Higher bandwidth capacity (100+ Gbps over long distances)
- Futureproofing for next-generation network technologies
What Is Multimode Fiber?
Multimode fiber has a larger core (50µm to 62.5µm), allowing it to carry multiple light modes simultaneously. This design enables high-speed data transmission over shorter distances, making it ideal for:
- Campus environments
- Data centers
- Building connections
- Fiber-to-the-home (FTTH) installations
- Fiber-to-the-node (FTTN) networks
While less expensive than single-mode cable, multimode fiber cables have distance limitations due to modal dispersion—the spreading of light signals as they travel through the larger core.
Standard Wavelengths
Fiber optics operate using specific wavelengths of light in the near-infrared spectrum, invisible to the human eye:
| Fiber Type | Operating Wavelengths | Characteristics |
|---|---|---|
| Multimode | 850nm and 1300nm | Lower-cost light sources (LEDs/VCSELs) |
| Single mode | 1310nm and 1550nm | Higher cost light sources (lasers) |
These wavelengths are selected to minimize attenuation (signal loss) while maximizing transmission distance. In optical communications, the 850nm and 1310nm wavelengths are often referred to as the “first window” and “second window.”
What Is the Difference Between 850NM & 1300NM Fiber Optic Cable?
In multimode applications:
- 850nm is the most common wavelength for short-distance transmission. It uses cost-effective VCSEL (Vertical-Cavity Surface-Emitting Laser) light sources but experiences higher attenuation rates.
- 1300nm offers higher bandwidth and lower attenuation than 850nm, making it suitable for longer multimode runs. However, 1300nm light sources tend to be more expensive.
For single-mode applications:
- 1310nm is the standard wavelength for most installations due to its excellent balance of cost and performance characteristics.
- 1550nm offers the lowest attenuation rates (approximately 0.2 dB/km), making it ideal for ultra-long-distance applications.
Have a network installation project?
Optic Cable Types
Single-Mode Fiber
OS1
OS1 single-mode fiber is primarily designed for indoor fiber optic cable applications:
- Applications: Ideal for fiber to the desktop (FTTD), fiber to the home (FTTH), and fiber to the node (FTTN)
- Construction: Tight-buffered for crush resistance and fire resistance
- Performance: Supports speeds up to 10 Gbps over distances of approximately 10km (6 miles)
- Jacket Color: Yellow (industry standard)
- Attenuation: ≤1.0 dB/km at 1310nm
OS2
OS2 single-mode fiber is optimized for long-haul and outdoor applications:
- Applications: Perfect for fiber optic backbone infrastructure, campus connections, and long-distance network links
- Construction: Loose tube design with gel-filled buffer tubes protecting optical fibers from moisture and environmental factors
- Performance: Supports speeds up to 100 Gbps over distances up to 200km (124 miles)
- Jacket Color: Yellow (industry standard)
- Attenuation: ≤0.4 dB/km at 1310nm (significantly lower than OS1)
Multimode Cable Type
OM1
OM1 is the original multimode cable standard:
- Status: Generally considered obsolete for new installations
- Core Size: 62.5µm
- Outer Jacket: Orange
- Performance: Supports 1 Gbps up to 300 meters at 850nm wavelength
- Bandwidth: 200 MHz·km at 850nm
- Applications: Legacy local area networks and private fiber networks
OM2
OM2 offers modest improvements over OM1:
- Status: Being phased out in favor of laser-optimized options for new installations
- Core Size: 50µm
- Outer Jacket: Orange
- Performance: Supports 1 Gbps up to 600 meters at 850nm wavelength (double the distance of OM1)
- Bandwidth: 500 MHz·km at 850nm
- Applications: Similar to OM1 but with extended reach capability
OM3
OM3 represents a significant leap in multimode performance through laser optimization:
- Key Feature: Laser-optimized for use with VCSEL light sources
- Core Size: 50µm
- Cable Jacket: Aqua
- Performance: Supports 10 Gbps up to 300 meters at 850nm wavelength
- Bandwidth: 2000 MHz·km at 850nm
- Applications: Data centers, enterprise networks, and campus environments requiring 10 G+ speeds
OM4
OM4 further enhances the laser-optimized multimode performance:
- Core Size: 50µm
- Cable Jacket: Aqua or violet
- Performance: Supports 10 Gbps up to 550 meters at 850nm wavelength
- Bandwidth: 4700 MHz·km at 850nm
- Applications: High-performance data centers and enterprise networks
- Standards Support: Compatible with 10GBASE-SR, 40GBASE-SR4, and 100GBASE-SR10 applications
The fiber is identified with an aqua-colored jacket.
OM5
OM5 is the newest multimode standard, introduced to support short-wavelength division multiplexing:
- Compatibility: Fully backward compatible with OM3 and OM4 installations
- Core Size: 50µm
- Cable Jacket: Lime green
- Performance: Supports multiple wavelengths between 850 and 953nm
- Bandwidth: 4700 MHz·km at 850nm (with enhanced performance at other wavelengths)
- Key Feature: Supports Shortwave Wavelength Division Multiplexing (SWDM), allowing multiple data channels on a single fiber
- Applications: High-density data centers requiring 40G/100G/400G connectivity
Comparison Table: Multimode Fiber Performance
| Fiber Type | Core Size | Jacket Color | Max Distance (1G) | Max Distance (10G) | Max Distance (40G) | Bandwidth (MHz·km) |
|---|---|---|---|---|---|---|
| OM1 | 62.5µm | Orange | 300m | 33m | Not supported | 200 |
| OM2 | 50µm | Orange | 600m | 82m | Not supported | 500 |
| OM3 | 50µm | Aqua | 1000m | 300m | 100m | 2000 |
| OM4 | 50µm | Aqua/Violet | 1000m | 550m | 150m | 4700 |
| OM5 | 50µm | Lime Green | 1000m | 550m | 150m (4 wavelengths) | 4700 (enhanced for WDM) |
Also read: Dark Fiber Network
FAQs
What are the four types of fiber optic connectors?
What are the four types of fiber optic connectors?
The most common fiber optic connectors include SC (Subscriber Connector), LC (Lucent Connector), ST (Straight Tip), and MTP/MPO (Multi-Fiber Push-On). Each connector type has its own design characteristics:
• SC connectors: Push-pull mechanism, widely used in telecommunications
• LC connectors: Small form factor with clip mechanism, common in high-density applications
• ST connectors: Bayonet-style connection, found in older installations
• MTP/MPO connectors: Support multiple fibers (usually 12 or 24) in a single connector, essential for 40G/100G/400G applications
What is the most common type of fiber optic cable?
OM3 and OM4 multimode fibers are the most common for short—to medium-distance applications (up to 550m) in enterprise environments due to their cost-effectiveness and support for 10G/40G/100G speeds. For long-distance applications requiring high bandwidth transmission, OS2 single-mode fiber dominates the market with its superior transmission capabilities.
How do I know what type of fiber optic cable I have?
You can identify your fiber optic cable type through several methods:
1. Jacket color:
• Yellow: Single-mode (OS1/OS2)
• Orange: Multimode (OM1/OM2)
• Aqua: Multimode (OM3/OM4)
• Lime green: Multimode (OM5)
2. Cable markings: Check the print along the cable jacket, which typically includes the fiber type designation (OS2, OM3, etc.)
3. Documentation: Review your network installation documentation or bill of materials
4 .Professional testing: Use an Optical Time Domain Reflectometer (OTDR) to determine cable type and characteristics precisely
Arrange Your Fiber Optic Cabling Consultation
With over 19 years of experience and 20,000+ successful installations, The Network Installers’ team of certified experts can help you select the optimal fiber optic solution for your business needs.
Whether you’re upgrading an existing network or planning a new installation, our 99% customer satisfaction rate demonstrates our commitment to excellence in fiber optic infrastructure.
Do you have questions about selecting the right fiber optic cable type for your upcoming project? Our experts are ready to provide personalized guidance.
Contact us today for a free consultation and no-obligation quote.
Have a network installation project?
