The "2.8" optical module refers to an SFP28 module, which has the same compact size as SFP and SFP+ modules.

SFP28 (Small Form-factor Pluggable 28) is a hot-pluggable optical transceiver widely used in enterprise networks, data centers, and carrier-grade deployments. Despite its higher data rate of 25 Gbps per channel, the SFP28 module maintains the same physical dimensions as SFP and SFP+ modules, allowing it to fit into the same ports and sockets as its predecessors . This standardization is defined by industry Multi-Source Agreements (MSA), ensuring mechanical interchangeability across vendors .

Key Features of SFP28 Modules

• Form Factor: Identical to SFP and SFP+; compact and pluggable for easy replacement and upgrades .
• Transmission Rate: Supports 25 Gbps, compared to SFP (1–4 Gbps) and SFP+ (up to 10 Gbps), .
• Compatibility: Can be backward compatible with SFP+ ports, though the link speed will be limited to the lower rate .
• Applications: Ideal for high-speed network upgrades, including 10G–25G–100G transitions in data centers .
• Electrical and Optical Standards: Adheres to MSA specifications for pinout, electrical interface, and optical performance, ensuring reliable interoperability .

Practical Considerations

When deploying SFP28 modules, it is important to verify line rate compatibility with the host switch or router, ensure the fiber type matches (single-mode or multi-mode), and confirm DDM/DOM support for real-time monitoring of temperature, voltage, and Tx/Rx power . The compact size allows for high-density port configurations without increasing the physical footprint of network equipment. In summary, the 2.8 optical module (SFP28) combines high-speed 25 Gbps performance with the same compact form factor as SFP and SFP+, making it a versatile choice for modern high-bandwidth networking environments .