SFP28 (Small Form-factor Pluggable 28) and QSFP28 (Quad Small Form-factor Pluggable 28) are both transceiver form factors used for high-speed network connections, but they differ in several key aspects:

1.Size: SFP28 is a smaller form factor compared to QSFP28. SFP28 modules are designed for applications where space is limited, while QSFP28 modules are larger and designed for higher density applications.

2. Number of channels: SFP28 supports a single 25 Gbps channel, while QSFP28 supports four 25 Gbps channels, making it capable of higher bandwidth.

3. Applications: SFP28 is commonly used for 25G Ethernet and 32G Fibre Channel connections, while QSFP28 is used for 100G Ethernet and 128G Fibre Channel connections.

4. Power consumption: SFP28 modules typically consume less power compared to QSFP28 due to their smaller size and lower number of channels.

Overall, the main difference between SFP28 and QSFP28 is their size, number of channels, and the applications for which they are commonly used.

Comparisons in SFP vs SFP+ vs SFP28 vs QSFP+ vs QSFP28

After figuring out what SFP/SFP+/SFP28/QSFP+/QSFP28 are, the following part will give detailed comparisons of SFP vs SFP+, SFP28 vs SFP+, QSFP vs QSFP28 and SFP28 vs QSFP28.

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