QSFP-DD is a new module and cage/connector system similar to current QSFP, but with an additional row of contacts providing for an eight lane electrical interface. It is being developed by the QSFP-DD MSA as a key part of the industry's effort to enable high-speed solutions. Quad Small Form-factor Pluggable Double Density (QSFP-DD) solution that fits into high-density switch and router client ports for optical interconnect links Powered by Greylock and Delphi DSP ASICs, and silicon photonic integrated circuits (PICs) for an optimized co-packaged design with 3D. Cisco offers a comprehensive range of pluggable optical modules in the Cisco® pluggables portfolio. Cisco offers a range of GBIC, SFP, XFP, SFP+, CXP, CFP, Cisco CPAK, and QSFP+ pluggable modules. Optech's 400 G QSFP‑DD digital coherent modules provide exactly that: a compact, high‑density form factor supporting up to 400 Gbps per wavelength, enabling both dense data‑center interconnect (DCI) links and regional long‑haul connectivity. 400G per wavelength, typically DP‑16QAM, OIF. Optical modules are optoelectronic devices that perform photoelectric and electro-optic conversions. Optical modules are classified by their packaging forms, with common types including SFP, SFP+, SFP28, QSFP+, QSFP28, QSFP56, QSFP-DD, QSFP112, and. QSFP DD, short for Quad Small Form-factor Pluggable Double Density, is a high-density optical transceiver form factor designed for high-speed networking applications. The QSFP-DD specification, maintained by the QSFP-DD.