Types of Fiber Optic Cables

Single-mode vs. Multi-mode Fibers

Single-mode Fiber:

  • Core Diameter: Smaller core diameter, typically around 8-10 micrometers.

  • Light Source: Uses a laser as a light source.

  • Distance: Capable of transmitting data over long distances with minimal signal loss.

  • Bandwidth: Higher bandwidth compared to multi-mode fiber, making it suitable for high-speed data transmission.

  • Applications: Ideal for long-distance telecommunications, internet backbone infrastructure, and cable TV networks.

Multi-mode Fiber:

  • Core Diameter: Larger core diameter, usually around 50-62.5 micrometers.

  • Light Source: Uses an LED or laser as a light source.

  • Distance: Suitable for shorter distances, typically up to 2 kilometers.

  • Bandwidth: Lower bandwidth compared to single-mode fiber but sufficient for most local area networks (LANs).

  • Applications: Commonly used in data centers, LANs, and short-distance communications.

Fiber Types

Fiber optic cables are classified based on their construction, performance, and the type of signal they carry. These classifications help in determining the appropriate fiber type for specific applications. Let's explore the different types of fiber optics: OM1, OM2, OM3, OM4, OM5, OS1, and OS2.

Multimode Fiber: OM1, OM2, OM3, OM4, OM5

OM1:

  • Core Size: 62.5µm

  • Bandwidth: 200 MHz*km at 850nm

  • Distance: Up to 300 meters for 10Gbps Ethernet

  • Color: Orange

  • Usage: Commonly used for short-distance data transmission, suitable for applications such as local area networks (LANs).

OM2:

  • Core Size: 50µm

  • Bandwidth: 500 MHz*km at 850nm

  • Distance: Up to 600 meters for 10Gbps Ethernet

  • Color: Orange

  • Usage: Similar to OM1, but supports higher bandwidth and longer distances.

OM3:

  • Core Size: 50µm

  • Bandwidth: 2000 MHz*km at 850nm

  • Distance: Up to 300 meters for 40Gbps and 100Gbps Ethernet

  • Color: Aqua

  • Usage: Designed for high-speed data transmission, ideal for data centers and backbone networks.

OM4:

  • Core Size: 50µm

  • Bandwidth: 4700 MHz*km at 850nm

  • Distance: Up to 400 meters for 40Gbps and 100Gbps Ethernet

  • Color: Aqua

  • Usage: Enhanced version of OM3, providing higher bandwidth and longer distance support, often used in data centers and high-performance computing networks.

OM5:

  • Core Size: 50µm

  • Bandwidth: Supports wideband multimode fiber (WBMMF) for wavelengths between 850nm and 953nm

  • Distance: Similar to OM4 for 40Gbps and 100Gbps Ethernet but supports Shortwave Wavelength Division Multiplexing (SWDM)

  • Color: Lime Green

  • Usage: Future-proofing for higher bandwidth applications, supporting multiple wavelengths on a single fiber.

Single-mode Fiber: OS1 and OS2

OS1:

  • Core Size: 9µm

  • Attenuation: Less than 1.0 dB/km

  • Distance: Up to 10 kilometers

  • Color: Yellow

  • Usage: Suitable for indoor applications, such as campus or enterprise networks. It uses tight-buffered cable construction.

OS2:

  • Core Size: 9µm

  • Attenuation: Less than 0.4 dB/km

  • Distance: Up to 200 kilometers

  • Color: Yellow

  • Usage: Designed for outdoor and long-distance applications, including telecommunications and large-scale data networks. It uses loose-tube construction for better performance over longer distances.

Key Differences and Applications

  1. Core Size and Bandwidth:

    • Multimode fibers (OM1 to OM5) have larger core sizes (50µm or 62.5µm) compared to single-mode fibers (9µm). Larger cores allow multiple modes of light to propagate, making them suitable for shorter distances with high data rates.

    • Single-mode fibers (OS1 and OS2) have smaller cores, allowing only one mode of light to propagate, reducing attenuation and increasing bandwidth over longer distances.

  2. Distance and Performance:

    • OM1 and OM2 are suitable for short distances and are typically used in LANs.

    • OM3 and OM4 are designed for higher speeds and longer distances, making them ideal for data centers.

    • OM5 supports SWDM, allowing for even higher bandwidth and future-proofing networks.

    • OS1 is used for indoor applications, while OS2 is used for longer distances and outdoor applications due to its lower attenuation.

  3. Color Coding:

    • Multimode fibers are color-coded for easy identification: OM1 and OM2 (orange), OM3 and OM4 (aqua), and OM5 (lime green).

    • Single-mode fibers are typically yellow.

Selecting the right fiber type depends on your specific needs, such as the required distance, data rate, and application environment. Understanding these types will help you make informed decisions for your fiber optic network.

Single-mode Fiber Applications:

  • Long-distance telecommunications

  • Internet backbone infrastructure

  • Submarine cable networks

  • High-speed data transmission in metropolitan area networks (MANs)

Multi-mode Fiber Applications:

  • Data centers

  • Local area networks (LANs)

  • Campus networks

  • Short-distance connections within buildings

Types of Fiber Optic Cable

Fiber optic cables come in various types, each designed for specific environments and applications. Understanding these types helps in selecting the right cable for your network's requirements. Here, we'll discuss the main types of fiber optic cables: indoor, outdoor, armored, and more.

Indoor Fiber Optic Cables

Indoor Cables:

  • Description: Designed for use within buildings.

  • Construction: Typically made with tighter buffer materials to protect the fibers from damage. They are flexible and easy to route through conduits and building structures.

  • Types:

    • Simplex and Duplex: Used for short-distance runs inside buildings, such as in data centers and office environments.

    • Distribution Cables: Contain multiple fibers bundled together, suitable for running to various locations within a building.

    • Breakout Cables: Similar to distribution cables but with individual jacketed fibers, making them easier to terminate.

Applications: Indoor cables are ideal for use in local area networks (LANs), data centers, and other in-building communications systems.

Outdoor Fiber Optic Cables

Outdoor Cables:

  • Description: Built to withstand harsher environmental conditions.

  • Construction: Features include waterproofing, UV-resistant jackets, and temperature-resistant materials. They are often gel-filled or have water-blocking tapes to prevent moisture ingress.

  • Types:

    • Loose-Tube Cables: Fibers are enclosed in a loose tube filled with a water-blocking gel. Suitable for aerial and underground installations.

    • Direct Burial Cables: Robustly constructed for burial directly in the ground without additional protection.

    • Aerial Cables: Designed to be suspended from poles or towers. Often have additional strength members to withstand wind and ice loading.

Applications: Outdoor cables are used in telecommunications, long-distance data transfer, and connections between buildings.

Armored Fiber Optic Cables

Armored Cables:

  • Description: Provide extra protection against physical damage.

  • Construction: Equipped with an additional layer of protection, typically a metal armor layer between the outer jacket and the inner core. Can be single-armored or double-armored for extra durability.

  • Types:

    • Indoor Armored Cables: Suitable for environments where the cable might be exposed to physical stress, such as in industrial settings or areas with high foot traffic.

    • Outdoor Armored Cables: Used in areas prone to rodent damage or where additional protection from environmental hazards is needed.

Applications: Ideal for use in hazardous environments, high-traffic areas, and situations where the cable might be exposed to potential damage.

Specialty Fiber Optic Cables

Plenum and Riser Cables:

  • Plenum Cables:

    • Description: Used in plenum spaces (the spaces used for air circulation in buildings, such as between floors and above drop ceilings).

    • Construction: Made from flame-retardant materials to prevent the spread of fire and reduce smoke.

    • Applications: Required by building codes for installation in plenum spaces.

  • Riser Cables:

    • Description: Designed for vertical runs between floors.

    • Construction: Flame-retardant, though not as stringent as plenum cables.

    • Applications: Used in elevator shafts and between floors within a building.

Aerial Fiber Optic Cables:

  • Description: Designed for overhead installations.

  • Construction: May include features like integrated messenger wires (for support) and weather-resistant jackets.

  • Applications: Used in telecommunications and internet service provider networks to connect poles and towers.

Armored Tactical Cables:

  • Description: Robust, flexible, and highly durable.

  • Construction: Designed to withstand harsh conditions, frequent deployment, and retrieval.

  • Applications: Commonly used in military applications, broadcast communications, and other environments requiring high reliability and durability.

Choosing the Right Cable

Selecting the appropriate fiber optic cable depends on several factors:

  • Environment: Consider whether the cable will be used indoors, outdoors, or in a specialized setting.

  • Protection Needs: Assess the level of protection required against physical damage, environmental conditions, and fire hazards.

  • Application: Determine the specific use case, such as data centers, telecommunications, industrial settings, or military applications.

Understanding these various types of fiber optic cables will help you make informed decisions to ensure optimal performance and reliability for your network.

When selecting fiber optic cables, it's important to consider not only the type of cable but also its configuration, such as the fiber count and the structure (ribbon or loose tube). These factors play a crucial role in the cable's application and performance.

Fiber Counts

Fiber optic cables come in various fiber counts, indicating the number of individual optical fibers within the cable. Common fiber counts range from as few as 2 fibers to over 1,000 fibers, depending on the application and network requirements.

Low Fiber Count:

  • 2 to 12 fibers

  • Applications: Suitable for small networks, home installations, and short-distance runs where fewer connections are needed.

Medium Fiber Count:

  • 12 to 72 fibers

  • Applications: Ideal for enterprise networks, data centers, and local area networks (LANs), where moderate scalability and connectivity are required.

High Fiber Count:

  • 72 to 144 fibers

  • Applications: Used in larger data centers, metro networks, and telecommunications, providing higher capacity and scalability.

Ultra-High Fiber Count:

  • 144 to 1,728 fibers (and more)

  • Applications: Necessary for large-scale network backbones, long-haul telecommunications, and densely populated urban areas requiring extensive connectivity.

Ribbon Fiber Optic Cables

Ribbon Cables:

  • Description: Composed of fibers arranged in parallel, flat ribbons. Each ribbon typically contains 12 fibers.

  • Construction: Ribbons can be stacked and bonded together, facilitating mass fusion splicing.

  • Advantages:

    • High Density: Offers a high packing density, allowing a large number of fibers in a compact cable.

    • Efficient Splicing: Simplifies mass fusion splicing, reducing installation time and costs.

  • Applications: Commonly used in data centers, large enterprise networks, and telecommunications where high fiber counts and efficient splicing are required.

Ribbon Fiber Optic Cable Structure:

  • Single Ribbons: Each ribbon contains 12 fibers, making splicing and termination efficient.

  • Mass Fusion Splicing: Enables simultaneous splicing of multiple fibers, speeding up the installation process.

  • Compact Design: High fiber count in a small form factor, suitable for high-density installations.