What Form Factors Are Used for 400G Optics and Cables?

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FiberMall

Answered on 9:55 am

There are two form factors defined for 400G optical modules and cables:

  • The OSFP: The OSFP stands for “Octal Small Form-factor Pluggable”. It is described as an “Octal” module because the electrical interface of an OSFP connector consists of 8 electrical lanes, running at 50Gb/s each, for a total bandwidth of 400Gb/s.
  • The QSFP-DD: The QSFP-DD stands for “Quad Small Form-factor Pluggable (QSFP) – Double Density (DD)”. The electrical interface of a QSFP-DD connector also has 8 electrical lanes, running at 50Gb/s each, for a total bandwidth of 400Gb/s. The QSFP-DD form factor is similar to the QSFP form factor, except a second row of electrical contacts has been added to increase the number of high-speed electrical lanes from 4 (in a QSFP) to 8 (in a QSFP-DD).

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