The FS QDD-SR4-400G Compatible LINK-PP module is a high-performance 400G QSFP-DD SR4 optical transceiver engineered for high-density data center links. Operating over 850nm multimode fiber (MMF), it converts an 8x50G PAM4 (400GAUI-8) electrical interface into 4x100G optical channels. Compliant with IEEE 802.3db, IEEE 802.3cd, and CMIS 5.2 standards, it consumes under 8W with low-latency retimed performance.
FS Part Number
QDD-SR4-400G
Vendor Name
LINK-PP
Form Factor
QSFP-DD
Max Data Rate
425Gbps
Connector
MPO-12/APC
Media
MMF
Wavelength
850nm
Max Cable Distance
30m@OM3/50m@OM4
Transmitter Type
VCSEL
Receiver Type
PIN
Modulation (Electrical)
8x50G-PAM4
Modulation (Optical)
4x100G-PAM4
DDM/DOM
Supported
Operating Temperature range
0°C to +70°C
Protocols
QSFP-DD MSA, CMIS Rev5.0, IEEE 802.3df-2024
Warranty
5 Years
Key Features of FS QDD-SR4-400G Compatible LINK-PP 400G QSFP-DD
The FS QDD-SR4-400G Compatible LINK-PP features integrated 4-channel VCSEL and PIN arrays, an MPO-12/APC optical interface, and sub-8W power consumption across 0°C to 70°C. Fully compliant with CMIS 5.2 and QSFP-DD MSA Type 2 specifications, it delivers robust, energy-efficient 400GE connectivity for modern networks.
The FS QDD-SR4-400G Compatible LINK-PP module is a hot-pluggable optical transceiver module designed for 400 Gigabit Ethernet applications, offering seamless interoperability, low power dissipation, and high port density for next-generation enterprise leaf-spine switch architectures.
QDD-SR4-400G: 400G Connectivity for MAN Core Networks
Designed for demanding telecom and data center environments, the QDD-SR4-400G delivers reliable 400G aggregation for MAN core networks and cloud facilities, facilitating low-latency throughput, breakout versatility, and scalable bandwidth expansion.
QDD-SR4-400G Module with 850nm Wavelength
Utilizing a nominal 850nm wavelength VCSEL transmitter array, the QDD-SR4-400G optical module ensures excellent spectral purity, minimal dispersion penalty, and stable 53.125 GBd PAM4 optical signal transmission across multimode fibers.
QDD-SR4-400G Module Supporting 50m Transmission
The QDD-SR4-400G transceiver supports short-reach transmission distances up to 30 meters over OM3 and 50 meters over OM4 multimode fiber, providing a cost-effective, high-speed interconnect solution for intra-datacenter server racks.
QDD-SR4-400G Module with MPO-12/APC Interface
Equipped with an industry-standard MPO-12/APC optical receptacle, the QDD-SR4-400G module minimizes optical return loss, optimizes fiber core alignment, and enables rapid parallel multi-fiber patching in ultra-dense cloud network cabling environments.
QDD-SR4-400G Module with DOM for Real-Time Monitoring
Featuring integrated Digital Optical Monitoring (DOM) via CMIS 5.2, the QDD-SR4-400G allows network engineers to monitor real-time operating parameters, including laser bias current, optical power levels, module temperature, and supply voltage.
The FS QDD-SR4-400G Compatible LINK-PP undergoes comprehensive qualification and holds international safety and environmental certifications, including CE, FCC, UKCA, UL, and REACH, verifying uncompromising quality and global regulatory adherence.
Every QDD-SR4-400G optical transceiver is subjected to an exhaustive quality testing program, validating signal integrity, parametric thresholds, and long-term durability to eliminate early network failure risks.
QDD-SR4-400G Quality Certifications
Fully compliant with RoHS, REACH, CE, and FCC directives, the QDD-SR4-400G meets rigorous electromagnetic compatibility and environmental protection benchmarks required for global tier-one data center deployments.
This product is in conformity with ISO9001. This system is valid to a company engaging in development, production and supply service of fiber optical products. Please contact us to learn more.
ISO/IEC 27001 is an international standard for managing and processing information security. This standard is jointly developed by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). It sets out requirements for establishing, implementing, maintaining, and continually improving an information security management system (ISMS). Ensuring the confidentiality, integrity, and availability of organizational information assets, obtaining an ISO 27001 certificate means that the enterprise has passed the audit conducted by a certification body, proving that its information security management system has met the requirements of the international standard. Please contact us to learn more.
This product is in conformity with ISO14001.It is intended for use by an organization seeking to manage its environmental responsibilities in a systematic manner that contributes to the environmental pillar of sustainability. Please contact us to learn more.
ISO 45001 is a global standard that sets out the requirements for an occupational health and safety management system (OH&SMS).
REACH is a European Union regulation concerning the Registration, Evaluation, Authorization and Restriction of Chemicals. It came into force on 1st June 2007 and replaced a number of European Directives and Regulations with a single system. The regulation aims to protect human health and environmental safety, maintain and improve the competitiveness of the EU chemical industry, and develop innovative capabilities for non-toxic and harmless compounds to prevent market fragmentation, increase the transparency of the use of chemicals, promote non-animal experiments, and pursue sustainable social development.Please contact us to learn more.
This product meets the applicable requirements of Directive (EU) 2015/863 of RoHS. It restricts the use of 10 hazardous materials in the manufacture of various types of electronic and electrical equipment: lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls, polybrominated diphenyl ethers, and four different phthalates. Please contact us to learn more.
This product fully accords with the FCC, which aims to manage the radio wave and magnetic fields more reasonably. Please contact us to learn more.
CB is an international system operated by IECEE. This product is based on IEC standards for testing the safety performance of electrical products. Please contact us to learn more.
This product fully accords with UKCA (UK Conformity Assessed) certificate, which signifies that it meets all relevant quality standards as well as health and safety requirements. Please contact us to learn more.
UL certification is a non-mandatory certification in the United States,mainly testing and certification of product safety performance.Its ultimate purpose is to obtain products with a fairly safe level for the market,and to contribute to ensuring human health and property safety.Please contact us to learn more.
QDD-SR4-400G Certified for Reliable Host-Device Compatibility
Tested extensively across mainstream network switches and routers, the QDD-SR4-400G ensures seamless multi-vendor compatibility, protocol stability, and hassle-free plug-and-play installation in diverse 400GE enterprise networking infrastructures.
Our state-of-the-art laboratory testing protocol guarantees that each QSFP-DD module delivers flawless transmission performance, superior thermal stability, and strict industry standard adherence.
Optical Spectrum Test
Validates central 850nm wavelength accuracy and verifies RMS spectral width under 0.6nm.
Eye Pattern Test
Evaluates PAM4 optical eye clarity, extinction ratio, and TDECQ parameters for signal integrity.
Bit Error Rate Test
Confirms pre-FEC BER compliance below 2.4E-4, guaranteeing error-free packet throughput under heavy load.
Temperature Test
Assesses continuous commercial 0°C to 70°C case temperature performance under extreme thermal conditions.
Product Shipping for FS QDD-SR4-400G Compatible LINK-PP 400G QSFP-DD
Each FS QDD-SR4-400G Compatible LINK-PP transceiver is packaged with specialized protective materials and shipped through expedited logistics channels to ensure safe, on-time worldwide delivery.
Anti-Static Protective Packaging
Shielded inside ESD-safe clamshell trays to prevent electrostatic discharge damage during transit.
Shock-Resistant Transport Protection
Reinforced outer cartons with custom cushioning absorb physical impacts during shipping.
Fast Order Processing and Dispatch
Optimized inventory management enables rapid order processing and immediate warehouse dispatch.
Global Logistics and International Delivery
Partnered with premier international carriers for dependable, trackable worldwide express delivery.
The FS QDD-SR4-400G Compatible LINK-PP features a hot-swappable QSFP-DD interface for straightforward installation in switch cages. Simply align the module, insert firmly until latched, and connect an MPO-12/APC cable to achieve instant 400G optical connectivity.
QDD-SR4-400G Technical Support
LINK-PP provides professional technical support, including pre-sales consultation, compatibility verification, and post-deployment troubleshooting to ensure smooth network operation.
Pre-Sales Technical Consultation
Professional technical guidance to help customers select the most suitable QDD-SR4-400G modules based on network architecture and application requirements.
Compatibility Verification Support
Compatibility checks and validation to ensure seamless operation with Cisco switches and other supported networking platforms.
Deployment & Installation Assistance
Step-by-step support for installation, configuration, and initial deployment to ensure stable and correct operation.
Long-Term Technical Assurance
Ongoing technical support throughout the product lifecycle to ensure reliable performance in enterprise and carrier-grade networks.
A:
You’ll need an MPO-12/APC (Angled Physical Contact) multimode fiber (MMF) patch cable. For a full 50-meter transmission distance, OM4 MMF is required. If you're utilizing existing OM3 fiber infrastructure, the maximum supported transmission distance will be limited to 30 meters. By
admin
A:
Absolutely! The LQD-M85400-SR4C is fully OEM compatible and tested extensively with Cisco, Arista, and other major brands. It supports CMIS 5.2, ensuring plug-and-play interoperability and accurate real-time DOM readings across your entire spine-leaf architecture. By
admin
A:
Yes, we definitely do! While the single-unit price is highly competitive, we offer tiered wholesale pricing designed for massive batch deployments. You can see automatic price drops starting at 10+ and 100+ units. Feel free to reach out to our sales engineering team for a custom enterprise quote. By
admin
A:
This specific LQD-M85400-SR4C model is a commercial temperature (0°C to 70°C) transceiver, heavily optimized for climate-controlled indoor data centers and enterprise server rooms. If you need industrial wide-temp optics (-40°C to 85°C) for challenging outdoor base station cabinets, please contact our support team and we will direct you to the correct ruggedized SKU! By
admin
Please write comments with more than three
character.
495187
495087
D***t
Austria
Verified
Purchase
5 .0
2026-03-27
As a network engineer, finding reliable 8x50G PAM4 optics is tough. This LINK-PP module operates perfectly within the 0 to 70°C range, maintaining stable 850nm transmission for our enterprise cloud servers. Highly recommended!
Please write comments with more than three
character.
495187
495091
S***r
Colombia
Verified
Purchase
5 .0
2026-02-25
Hooked up these 400G MPO-12/APC modules for our campus core switches. The 400GAUI-8 interface synced instantly with our Mellanox hardware. Way cheaper than original brands without sacrificing any throughput or latency.
Please write comments with more than three
character.
495187
495095
M***s
Italy
Verified
Purchase
5 .0
2026-02-14
We just finished a massive batch deployment of these QSFP-DD 400G transceivers in our spine-leaf architecture. The DOM real-time monitoring works perfectly via CMIS 5.2, and power dissipation stayed strictly under 8W.
United States · English · USD
