Single-mode fiber optic cables (SMF) are designed for long-distance, high-speed transmission with a core diameter of 8–10 µm, supporting wavelengths of 1310 nm and 1550 nm, and are available in OS1, OS2, and ITU-T G.652/G.655 standard models.

Core Specifications

• Core Diameter: 8–10 µm, allowing only a single light mode to propagate, minimizing modal dispersion and enabling long-distance transmission up to 100 km without regeneration .
• Cladding Diameter: Typically 125 µm.
• Wavelengths: Optimized for 1310 nm and 1550 nm, with some fibers supporting the L-band (1565–1625 nm) for DWDM applications .
• Attenuation: Low attenuation, typically 0.35 dB/km at 1310 nm and 0.22 dB/km at 1550 nm, depending on fiber type and quality.
• Dispersion: Minimal modal dispersion; chromatic dispersion varies by fiber type (e.g., G.652.D is optimized for low dispersion across the full spectrum), .

Common Models and Standards

• OS1: Indoor, tight-buffered fiber for short-distance applications (up to 10 km). Suitable for campus networks, building backbones, and data center interconnects .
• OS2: Outdoor, loose-tube fiber for long-distance applications (up to 200 km). Used in backhaul networks, FTTH, and WDM/DWDM systems .
• ITU-T G.652: Standard single-mode fiber (non-dispersion-shifted). Subtypes include G.652.B and G.652.D, with G.652.D being “future-proof” for DWDM and 5G fronthaul .
• ITU-T G.653: Dispersion-shifted fiber optimized for 1550 nm, minimizing dispersion for long-haul WDM systems .
• ITU-T G.654: Cut-off shifted fiber with low loss at 1550 nm, suitable for ultra-long-haul applications .
• ITU-T G.655: Non-zero dispersion-shifted fiber (NZ-DSF) for high-power, dense WDM systems, reducing four-wave mixing .

Commercial Variants

• Draka SMF: Supports 1310 nm, 1550 nm, and L-band operation, with low dispersion at 1310 nm. Available in loose tube, tight buffered, ribbon, and central tube constructions. Enhanced with ColorLock™ coating for durability and APVD™ manufacturing for high purity .
• Other Manufacturers: Many vendors provide OS1/OS2 fibers with dual-layer protective coatings, gel-free designs, and high-speed support up to 100 Gbps over 10 km .

Applications

• Indoor: OS1 fibers for enterprise networks, campus backbones, and inter-rack connections.
• Outdoor: OS2 fibers for telecom backbones, FTTH, metro networks, and long-haul DWDM systems.
• High-Speed Networks: G.652.D and G.655 fibers for DWDM, 5G fronthaul, and high-capacity data center interconnects.

Summary

Single-mode fiber optic cables are optimized for long-distance, high-speed transmission with minimal dispersion. Selection depends on deployment environment (indoor vs. outdoor), distance, and network requirements. OS1 and OS2 are the most common commercial models, while ITU-T G.652, G.653, G.654, and G.655 standards define performance characteristics for telecom and high-capacity networks .