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The Cisco QDD-400G-FR4-S Compatible LINK-PP module is a commercial-grade 400G QSFP-DD optical transceiver engineered for high-density networking. Compliant with 400GBASE-FR4 standards, it utilizes 8x53.125Gb/s PAM4 electrical lanes and 4x106.25Gb/s optical channels. It features an integrated EML laser, a PIN receiver, and a duplex LC connector, delivering stable 400Gbps aggregation over single-mode fiber with a maximum power consumption under 10W.
| Cisco Part Number | QDD-400G-FR4-S | Vendor Name | LINK-PP |
| Form Factor | QSFP-DD | Max Data Rate | 400Gbps |
| Connector | Duplex LC | Media | SMF |
| Wavelength | 1271nm, 1291nm, 1311nm, 1331nm | Max Cable Distance | 2km |
| Transmitter Type | CWDM EML | Receiver Type |
PIN |
| Max Power Consumption | 9.5W | Protocols | IEEE 802.3bs, QSFP-DD MSA |
| DDM/DOM | Supported | Operating Temperature range |
0°C to +70°C |
This hot-pluggable QSFP-DD transceiver offers high port density and low power consumption for modern networks. Leveraging advanced 4-level pulse amplitude modulation, it integrates digital optical monitoring for comprehensive performance tracking. It provides cost-effective, high-bandwidth interconnectivity with broad third-party host compatibility.
The Cisco QDD-400G-FR4-S Compatible LINK-PP optical module offers a reliable, plug-and-play solution for upgrading hardware to 400G. Designed for robust data aggregation, it minimizes footprint while maintaining superior thermal dissipation in high-density switch environments.
Tailored for next-generation cloud infrastructure, the QDD-400G-FR4-S delivers hyperscale bandwidth to handle massive traffic demands. It bridges spine-and-leaf switches efficiently, ensuring ultra-low latency and consistent throughput required for modern AI and enterprise cloud environments.
By incorporating integrated Coarse Wavelength Division Multiplexing technology, this module multiplexes four distinct channels onto a single fiber pair. This architecture dramatically reduces cabling complexity and optimizes existing fiber infrastructure capital expenditures.
Operating on four precise CWDM grid wavelengths of 1271nm, 1291nm, 1311nm, and 1331nm, the module minimizes optical crosstalk. This specific wavelength configuration guarantees clean grid spacing and optimized signal integrity over single-mode links.
Engineered for localized reach, this transceiver supports error-free link distances up to 2km using standard G.652 single-mode fiber. It serves as the ideal reach-optimized solution for intra-datacenter interconnects and campus backbone wiring.
Featuring an industry-standard duplex LC optical interface, this module enables secure, tactile fiber patching. The standard LC connector format ensures seamless integration with legacy patch panels, clean mating interfaces, and low insertion loss.
Equipped with built-in Digital Optical Monitoring via the CMIS interface, network administrators can track diagnostics in real time. The module continuously reports internal temperature, supply voltage, laser bias current, and received optical power levels.
This transceiver holds complete international regulatory approvals, satisfying rigorous global standards for electronic products. It complies fully with standard multi-source agreements, ensuring safe, law-compliant deployment across global network infrastructures.
LINK-PP subjects every single transceiver to a comprehensive multi-stage validation pipeline. Technicians rigorously verify every parameter, ensuring that each module leaves the factory performing at peak physical and optical excellence.
Manufactured under strict ISO9001 quality management guidelines, this module holds CE, FCC, and RoHS environmental certifications. These credentials guarantee toxic-free materials, electromagnetic safety compliance, and long-term operating reliability.
Extensive hardware interoperability matrices certify this transceiver for seamless use with major switch and router vendors. It guarantees immediate host recognition, eliminating system faults or communication lockouts upon installation.
Every QDD-400G-FR4-S module undergoes strict parametric validation. Our comprehensive testing protocol ensures optimal data transmission, mechanical integrity, and absolute reliability under maximum network workloads.
Precision spectrum analysis verifies correct CWDM central wavelengths and side-mode suppression ratios.
PAM4 eye diagram testing ensures clean optical signals, low jitter, and excellent signal-to-noise ratios.
Strict PRBS testing guarantees error-free data throughput, fully satisfying mandatory host KP4 FEC benchmarks.
Thermal chamber cycling validates commercial-grade stability across variable operating environments from 0°C to 70°C.
We implement specialized logistic workflows and standardized defensive packaging for all transit. Your modules arrive safely, secured against environmental hazards and transportation stresses, ready for deployment.
Each module is sealed inside a premium ESD-safe anti-static blister package.
Heavy-duty cushioned outer boxes shield the optics from accidental drops and vibrations.
Streamlined warehousing ensures swift verification, rapid packaging, and prompt courier handover.
Partnering with leading express carriers guarantees rapid, tracked delivery to any worldwide destination.
This application showcase demonstrates the simple hot-swapping installation of the transceiver into standard high-density 400G enterprise switches. Watch how the host system instantly discovers the module, initiates the DOM link diagnostics, and establishes a stable 2km fiber link.
LINK-PP provides professional technical support, including pre-sales consultation, compatibility verification, and post-deployment troubleshooting to ensure smooth network operation.
Professional technical guidance to help customers select the most suitable QDD-400G-FR4-S modules based on network architecture and application requirements.
Compatibility checks and validation to ensure seamless operation with Cisco switches and other supported networking platforms.
Step-by-step support for installation, configuration, and initial deployment to ensure stable and correct operation.
Ongoing technical support throughout the product lifecycle to ensure reliable performance in enterprise and carrier-grade networks.
LINK-PP provides after-sales support for the smooth deployment and reliable operation of the optical modules.
15-day no-reason return and refund
Free replacement for dead-on-arrival (DOA) or defective items within the initial period
Free repair services for manufacturing defects throughout the warranty period
Warranty exclusions and conditions apply
Compatible | Cisco | Cisco | Cisco | Cisco | Cisco | Cisco |
Data Rate (Max) | 400Gbps | 400Gbps | 400Gbps | 400Gbps | 400Gbps | 400Gbps |
Wavelength | 1271nm, 1291nm, 1311nm, 1331nm | 1528.77~1566.52nm | 1310nm | 1528.77nm-1567.13nm | 1528.77~1566.52nm | 1528.77~1566.52nm |
Connector | Duplex LC | Duplex LC | Duplex LC | Duplex LC/UPC | Duplex LC | Duplex LC/UPC |
Cable Distance (Max) | 2km | 120km | 30km | 600km | 120km | 120km |
Cable Type | SMF | SMF | SMF | SMF | SMF | SMF |
Power Consumption | 9.5W | |||||
Operating Temperature | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C |
Vendor Name | LINK-PP | LINK-PP | LINK-PP | LINK-PP | LINK-PP | LINK-PP |
Form Factor | QSFP-DD | QSFP-DD | QSFP-DD | QSFP-DD | QSFP-DD | QSFP-DD |
Transmitter Type | CWDM EML | - | EML | - | ||
Receiver Type | PIN | - | APD | - | ||
Protocols | IEEE 802.3bs, QSFP-DD MSA | OIF 400ZR, OIF-CMIS-05.2, OIF-C-CMIS-01.2, QSFP-DD-Hardware-Rev6.3, IEEE Std 802.3-2018 | QSFP-DD MSA, CMIS Rev4.0, IEEE 802.3, IEEE 802.3bs, OIF 56G PAM4 | Open ZR+ MSA 2.0 and OIF-400ZR-02.0, OIF-CMIS-05.2, OIF-C-CMIS-01.2, QSFP-DD-Hardware-Rev6.3, IEEE Std 802.3-2018 | OIF 400ZR, OIF-CMIS-05.2, OIF-C-CMIS-01.2, QSFP-DD-Hardware-Rev6.3, IEEE Std 802.3-2018 | OIF 400ZR, OIF-CMIS-05.2, OIF-C-CMIS-01.2, QSFP-DD-Hardware-Rev6.3, IEEE Std 802.3-2018 |
DDM/DOM | Supported | Supported | Supported | Supported | Supported | Supported |
| Pictures | ID# | Description | Price | Stock | Add to Cart |
Q: Hey, we're running a mix of Cisco Nexus and Arista switches in our core network. Will this 400G FR4 transceiver work seamlessly across both brands without raising third-party optic alarms? By S***e on 2026-02-17
A: Absolutely! The LQD-CW400-FR4C is fully OEM-compatible and coded to support Cisco, Arista, and other major networking brands like Juniper and Mellanox. You can deploy it confidently in mixed-switch environments without triggering compatibility errors. By admin on 2026-02-17
Q: Just to confirm before purchasing for our campus fiber ring—does this transceiver use a standard duplex LC connector, and is it compatible with our existing OS2 single-mode fiber (SMF)? By R***r on 2025-08-27
A: Yes! This 400G QSFP-DD optical module features an industry-standard Duplex LC interface. It is fully compatible with standard OS2 single-mode fiber (SMF) and supports transmission distances up to 2km utilizing 1310nm CWDM4 wavelengths. By admin on 2025-08-27
Q: I'm an IT procurement manager looking to order 200 units for a new datacenter build in Frankfurt. Do you offer B2B bulk discounts for large volume purchases? By D***t on 2025-06-21
A: Yes, we provide competitive tiered pricing for enterprise B2B customers. For an order of 200 pieces of our 400G QSFP-DD modules, you'll receive a significant bulk discount over the standard unit price. Please contact our live sales team for a custom quote! By admin on 2025-06-21
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