Door-to-door optical core router QSFP-DD

QSFP-DD digital coherent optics enable direct, high-speed 400G and 800G connections from routers to DWDM networks, eliminating the need for intermediate transponders. Overview of QSFP-DD ModulesQSFP-DD (Quad Small Form Factor Pluggable Double Density) is a high-density optical transceiver standard that extends the QSFP family from 4 to 8 high-speed electrical lanes, supporting 400G and 800G aggregate throughput using PAM4 signaling. It maintains backward mechanical compatibility with QSFP28 and QSFP56, allowing seamless upgrades in high-density router and switch deployments while doubling port density without increasing power or space requirements.

QSFP-DD modules are designed for cloud-scale, AI-driven, and carrier-grade networks. 400G QSFP-DD Digital Coherent OpticsCisco and other vendors offer 400G digital coherent QSFP-DD modules compliant with the OIF 400ZR standard. These modules support point-to-point transmission up to 120 km over DWDM networks using C-band tunable optics and LC duplex connectors.

By plugging these modules directly into routers or switches, operators can bypass traditional transponder or muxponder layers, reducing capital and operational expenditures, lowering power consumption, and simplifying network management. The modules are optimized for IP-over-DWDM architectures, making them suitable for metro and regional core networks. 800G QSFP-DD Coherent OpticsFor higher-capacity applications, 800G QSFP-DD modules (including 800ZR and 800ZR+) enable single-wavelength 800G traffic over amplified DWDM links up to 120 km for 800ZR and beyond 1000 km for 800ZR+.

These modules leverage advanced CMOS and coherent technologies, supporting OpenROADM PCS modes for interoperability. They are ideal for data center interconnects (DCI), metro, and regional service provider networks, providing high-performance, long-reach optical connectivity directly from router ports.

Key Benefits for Door-to-

Door Core Routing

Direct integration: QSFP-DD modules plug directly into router ports, eliminating intermediate optical equipment. High density: Double the port density in the same chassis footprint. Cost efficiency: Reduces capital and operational expenses by removing transponders and muxponders.

Energy and space savings: Lower power consumption and cooling requirements in central offices or co-location sites. Scalability: Supports 400G and 800G speeds, enabling future-proof network upgrades. Standards compliance: OIF 400ZR, OpenZR+, and QSFP-DD MSA ensure interoperability across vendors.

ConclusionDoor-to-door optical core routers equipped with QSFP-DD digital coherent optics provide a compact, high-performance solution for modern DWDM networks. They enable direct, high-speed connections from routers to optical transport networks, supporting 400G and 800G traffic with reduced complexity, lower costs, and improved operational efficiency, making them ideal for metro, regional, and data center interconnect applications.