• SFP-DD is a new module and cage/connector system similar to current SFP, but with an additional row of contacts providing for a two lane electrical interface. It is being developed by the SFP-DD MSA as a key part of the industry’s effort to enable high-speed solutions. The product will support DAC cables, optical modules and AOC’s, both legacy SFP+ and new SFP-DD styles.
  • SFP-DD Hardware Specification for SFP DOUBLE DENSITY 2X PLUGGABLE TRANSCEIVER - Rev 1.1

Our Features

File server interconnect today is often an underpopulated zQSFP interface, using 2 of the potential 4 lanes to provide 100 Gb/s capability

SFP-DD will offer backwards compatibility to all current SFP style interfaces

Cable assembly:

  • SFP-DD and QSFP-DD naturally yield break out cables, 400 Gb/s to 4 100 Gb/s lanes
  • Support 200 Gb/s to 50 Gb/s if required
  • Max Twin-ax Gauge – 28 AWG for breakout cable at this time.
  • Target 3m 28 AWG Twin Ax cable assembly

SMT connector and 1X1 cage

Targeting support up to 3.5w optical modules in an enterprise environment

SFP-DD electrical interfaces will employ 2 lanes that operate up to 25 Gbps NRZ modulation or 56 Gbps PAM4 modulation, providing solutions up to 50 Gbps or 112 Gbps PAM4 aggregate


  • Concept leverages QSFP-DD SMT, excellent SI.
  • Reduced board real estate and panel beach front as compared to zQSFP
  • Mates existing SFP+ cables, modules and AOC’s as well as new SFP-DD interfaces
  • Potential to provide 2 additional lanes for future proof bandwidth upgrades – need to confirm based on pin out
  • SFP-DD efficiently supports 4 port breakouts (2 lanes per port) from QSFP-DD
  • In general, SFP-DD is a natural complement to QSFP-DD interfaces
Alibaba Dell
Infinera Light
Inno Light


The SFP-DD MSA Group is addressing the technical challenges of achieving a double-density interface and ensuring mechanical interoperability for module components produced by different manufacturers, while maintaining excellent SI and supporting up to 3.5w for optical modules in an enterprise environment

Collaboration through the MSA will enable faster implementation and easier operation of the SFP-DD pluggable interface in networking equipment