Optical modules use various electrical and optical interfaces, including SFP, SFP+, QSFP, OSFP, and CFP2, with prices ranging from $20 for basic SFP modules to several thousand dollars for high-speed coherent modules.

Common Optical Module Interfaces

Electrical Interfaces:

• SFP/XFP: Early small form-factor pluggable modules; SFP supports up to 4.25 Gbps, XFP up to 10 Gbps. Electrical interfaces include XFI for XFP and SFI for SFP+ modules .
• QSFP/QSFP28/QSFP-DD: Quad small form-factor pluggable modules supporting 40G, 100G, and 400G speeds. Electrical interfaces include CAUI-4, 4x25G, 8x50G, or 800GAUI-8 for OSFP/QSFP-DD .
• OSFP: Designed for 400G and 800G applications, supporting high-density data center deployments with electrical interfaces like OSFP MSA .
• CFP2-ACO: Analog coherent optics modules for long-haul coherent transmission, with DSP on the main board and analog optical components on the module . Optical Interfaces:
• LC Connector: Common for single-mode and multimode fiber; small form factor, widely used in SFP/SFP+ modules .
• SC Connector: Larger ferrule (2.5mm), push-pull design; gradually replaced by LC .
• MPO/MTP: Multi-fiber connectors integrating 12–24 fibers (up to 144 in some cases), used in 40G/100G/400G parallel optics . Fiber Type Compatibility:
• Single-mode fiber (SMF): Typically paired with 1310nm or 1550nm modules for long-distance transmission (up to 80 km), .
• Multimode fiber (MMF): Paired with 850nm modules for short-distance links (up to 300 m), .

Price Ranges

• Basic SFP modules (1G/10G, multimode): $20–$100 per module.
• SFP+ and QSFP+ (10G–40G, single-mode or multimode): $100–$500 depending on distance and vendor.
• QSFP28/OSFP (100G–400G, multimode or single-mode): $400–$1,500 for standard data center modules .
• High-speed coherent modules (CFP2-ACO, 400G–800G, long-haul): $2,000–$10,000+ depending on modulation format (DP-QPSK, QAM-16) and vendor .

Key Considerations

1. Rate and Distance Matching: Ensure the module's data rate matches the switch or router port and the fiber type matches the module wavelength .
2. Form Factor Compatibility: SFP, QSFP, OSFP, and CFP2 modules are not interchangeable; check device support.
3. Connector Type: LC, SC, or MPO/MTP must match the patch panel or fiber cabling.
4. Power Consumption: High-speed modules (400G/800G) may consume 8–13.5 W per module .
5. Vendor and Brand: Prices vary significantly between OEMs and third-party vendors; certified modules often cost more but ensure reliability. By selecting the appropriate interface type, fiber type, and form factor, you can optimize both performance and cost for your network deployment.