Designed in a compact QSFP-DD form factor, the module enables 400Gbps coherent transmission over DWDM with a typical reach of up to 40km (unamplified), making it a strong fit for metro DCI, campus interconnect, and regional rings. 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. The 400G QSFP-DD ZR+ is designed to 100G/200G long haul and 300G/400G Metro IP over DWDM applications without inline chromatic dispersion compensation. 400G DP-16QAM modulation format. With one VOA inside the TX optical path the out output optical power has 4dB attenuation window. Nokia coherent routing utilizes a new generation of digital coherent optics (DCOs) equipped in router interface ports to n the router-pluggable QSFP-DD format. Developed by the Optical Internetworking Forum (OIF) and released in March 2020, 400ZR is. Power high-capacity metro and regional links with a generic compatible 400G DCO QSFP-DD optical module built for modern DWDM coherent networks. This tunable coherent transceiver combines high spectral efficiency with operational simplicity—ideal for service providers, data centers, and enterprises. Cisco QSFP-DD and OSFP 800G ZR/ZR+ digital coherent optics modules enable 800G traffic over amplified Dense Wavelength-Division Multiplexing (DWDM) links up to 120 km for 800ZR and over 1000 km for 800G ZR+.