CISCO QDD-400G-ZR-S DCO QSFP-DD Optical Transceiver

Cisco QDD-400G-ZR-S is a Digital Coherent Optics (DCO) transceiver designed for 400G Ethernet connectivity in point-to-point topologies. Compliant with the OIF 400ZR standard, it is optimized for high-performance data center interconnects (DCI) and metro network applications.

Core Technical Specifications
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According to official Cisco documentation and technical datasheets, the primary specifications include:

* Form Factor: QSFP-DD (Quad Small Form-factor Pluggable Double Density).

* Data Rate: 400 Gbps.

* Reach: Supports up to 120 km with amplified links and up to 40 km in unamplified point-to-point configurations.

* Modulation: Employs DP-16QAM (Dual-Polarization 16-state Quadrature Amplitude Modulation).

* Wavelength Range: Tunable across the C-band (191.3 to 196.1 THz) with 100GHz and 75GHz grid spacing.

* Power Consumption: Maximum power consumption is typically ≤18W.

* Forward Error Correction (FEC): Uses C-FEC (Concatenated FEC) as per the OIF 400ZR implementation protocol.

* Optical Interface: Duplex LC connector.

Key Features and Use Cases
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* Interoperability: Complies with OIF-400ZR and QSFP-DD MSA standards, ensuring compatibility with various industry-standard 400G ports.

* Applications: Specifically cost-optimized for unamplified point-to-point links and standardized for simple network designs such as data center-to-peering sites.

* Monitoring: Supports integrated Digital Diagnostic Monitoring (DDM/DOM) for real-time tracking of operating parameters like optical power and temperature.

* Temperature Ranges: Standard operating temperature is 0°C to 70°C, with short-term support for up to 80°C for limited durations (e.g., 96 consecutive hours).

Platform Compatibility
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This module is supported across several high-density Cisco networking platforms, including:

* Nexus 9000 Series: Specifically supported on GX and FX2 models like the Nexus 9316D-GX and 9336C-FX2.

* NCS 5500 Series: Modular chassis support typically requires specific line cards such as the NC57-18DD-SE.

* ASR 9000 Series: Supported on 400G digital coherent optic interfaces.