Optech OSFP-800G-2xLR4 Solution for NVIDIA Quantum-2 and Spectrum-4 Networks

As AI clusters and high-performance data centers expand, network operators need optical solutions that combine high bandwidth, long transmission distance, dense port utilization, and dependable platform compatibility.

Optech’s OSFP-800G-2xLR4 optical transceiver is designed for long-reach, high-capacity switch interconnects in NVIDIA networking environments. Positioned as a compatible alternative to the NVIDIA MMS4X90-NR, the module integrates two independent 400G LR4 optical engines into one twin-port OSFP form factor.

This architecture is highly relevant to networks built around:

• NVIDIA Spectrum-4 SN5600 Ethernet switches
• NVIDIA Quantum-2 QM9700 InfiniBand switches
• AI and GPU cluster backbones
• High-performance computing fabrics
• Campus and inter-building data center links
• Long-reach switch-to-switch connectivity

The accompanying image shows an 800G optical link connected to an NVIDIA SN5600 switch, illustrating Optech’s focus on physical platform testing and real deployment conditions.

What Is the NVIDIA MMS4X90-NR?

The NVIDIA MMS4X90-NR is an 800Gb/s twin-port OSFP transceiver containing two 400Gb/s LR4 optical engines. NVIDIA specifies two duplex LC optical interfaces, single-mode fiber transmission, a multiplexed 1310nm wavelength grid, and 100G-PAM4 signaling on eight electrical and optical lanes. The official ordering description lists the module for reaches of up to 10km.

The NVIDIA ordering information identifies:

Optech’s compatible OSFP-800G-2xLR4 solution is intended to provide the same practical deployment concept: two long-reach 400G optical connections from a single OSFP switch cage.

How OSFP-800G-2xLR4 Works

The module contains two independent 400G LR4 transceiver engines. Each engine uses four optical wavelengths, with every wavelength carrying a 100G PAM4 signal.

Together, the module provides:

• Eight electrical lanes of 100G-PAM4
• Two independent 400G optical links
• Four CWDM wavelengths per 400G link
• Two duplex LC connectors
• An aggregate electrical capacity of 800Gb/s

NVIDIA’s specification lists a maximum power dissipation of 17W, OSFP MSA compliance, CMIS 5.0 management support, hot-pluggable operation, and a finned housing for thermal management.

Why the Twin-Port Architecture Matters

A conventional single-port 400G module uses one switch cage for one 400G connection. A twin-port OSFP module places two 400G engines into one OSFP cage.

This design can provide several advantages:

• Higher 400G port density
• Better use of available switch cages
• Two independently routable optical links
• Easier 800G aggregation
• Flexible switch-to-switch network design
• Compatibility with duplex LC structured cabling

For networks that need long reach but prefer standard duplex fiber infrastructure, 2xLR4 can be easier to integrate than parallel-optics solutions requiring MPO-based cabling.

OSFP-800G-2xLR4 with the NVIDIA Spectrum-4 SN5600

The NVIDIA SN5600 is a Spectrum-4-based Ethernet switch designed for AI, cloud, spine, and super-spine applications.

NVIDIA documents the SN5600 with:

• 64 OSFP interfaces
• Up to 64 × 800GbE
• Breakout support for up to 128 × 400GbE
• Further breakout support for lower-speed interfaces
• Up to 51.2Tb/s of switching capacity

This makes the SN5600 particularly relevant to twin-port modules because each OSFP cage can support dense 800G connectivity or multiple logical 400G links.

Typical SN5600 Deployment

An Optech OSFP-800G-2xLR4 solution can be used for applications such as:

• SN5600-to-SN5600 long-reach links
• AI Ethernet spine and super-spine connectivity
• Two independent 400G links from one OSFP cage
• Inter-building data center connections
• 800G aggregated links over two duplex LC fiber pairs
• Structured cabling environments based on single-mode LC fiber

The image provided with this article shows an Optech optical link installed in an SN5600 test environment. Platform-level testing is important because compatibility depends not only on optical specifications, but also on module coding, CMIS behavior, firmware recognition, thermal limits, and link configuration.

OSFP-800G-2xLR4 and the NVIDIA Quantum-2 QM9700

The NVIDIA QM9700 belongs to the Quantum-2 NDR InfiniBand switch family. NVIDIA specifies 32 physical OSFP interfaces that provide 64 non-blocking NDR 400Gb/s ports, with aggregate bidirectional throughput of up to 51.2Tb/s. The platform can also support up to 128 ports at 200Gb/s through port splitting.

The QM9700 is widely associated with:

• AI training clusters
• HPC InfiniBand fabrics
• GPU scale-out networks
• Scientific computing
• High-performance storage fabrics
• Low-latency leaf-spine or fat-tree designs

Because InfiniBand and Ethernet platforms can require different firmware profiles and host configurations, an OSFP-800G-2xLR4 module should be coded and validated specifically for the intended switch, firmware version, protocol, and operating mode.

NVIDIA’s published MMS4X90-NR documentation explicitly identifies Ethernet firmware and Spectrum-4 switch applications, while also including QM9700-related thermal guidance. Therefore, customers planning QM9700 deployment should confirm the required NVIDIA firmware support and Optech compatibility profile before ordering.

Quantum-2 vs Spectrum-4: What Is the Difference?

NVIDIA Quantum-2

Quantum-2 is NVIDIA’s InfiniBand networking architecture. It is primarily designed for extremely low-latency, high-throughput communication in AI and HPC fabrics.

The QM9700 uses Quantum-2 technology and provides 64 NDR 400Gb/s ports through 32 twin-port OSFP interfaces.

NVIDIA Spectrum-4

Spectrum-4 is NVIDIA’s high-performance Ethernet switching architecture. It is used in AI Ethernet, cloud, storage, and large-scale data center networks.

The SN5600 uses Spectrum-4 technology and provides 64 physical 800GbE OSFP ports, with the flexibility to operate as as many as 128 400GbE interfaces.

Why Protocol-Specific Validation Is Necessary

Although both platforms use OSFP interfaces, physical fit alone does not guarantee complete interoperability. Validation should cover:

• Ethernet or InfiniBand protocol mode
• Module EEPROM coding
• CMIS management behavior
• Switch firmware recognition
• Lane configuration
• Port splitting
• FEC operation
• Optical power and BER performance
• Thermal performance
• Alarm and diagnostic reporting

This is why Optech emphasizes testing on actual networking platforms rather than relying only on mechanical and optical specification matching.

Key Benefits of Optech’s OSFP-800G-2xLR4 Solution

1. Two 400G LR4 Links in One OSFP Module

The twin-port architecture gives network operators two independent 400G optical links while occupying one OSFP cage.

2. Long-Reach Single-Mode Connectivity

The NVIDIA reference product is listed for reaches up to 10km, making this product category suitable for campus, metro-edge, and inter-building data center links.

3. Duplex LC Cabling

Each 400G LR4 engine uses a duplex LC interface. This supports familiar structured single-mode fiber infrastructure and avoids the need for high-fiber-count parallel MPO cabling.

4. High Port Density

Twin-port OSFP designs help increase the number of available 400G logical links. This is particularly useful on high-radix switches such as the SN5600 and QM9700.

5. Strong Fit for AI and HPC Infrastructure

The solution can address the high-bandwidth inter-switch connections required in AI Ethernet and HPC network architectures.

6. Platform-Oriented Compatibility Support

Optech can support coding, firmware alignment, link testing, and diagnostic verification according to the target platform and deployment requirements.

7. Taiwan-Based Manufacturing Support

As a Taiwan optical transceiver manufacturer, Optech can provide product configuration support, compatibility services, quality control, and flexible project coordination for international customers.

Typical Application Scenarios

AI Ethernet Spine Interconnects

On Spectrum-4 SN5600 platforms, 2xLR4 modules can provide high-density long-reach connections between spine and super-spine switches.

HPC and InfiniBand Network Planning

For Quantum-2 QM9700 deployments, compatible optical modules can be evaluated for long-reach InfiniBand connections, subject to protocol and firmware qualification.

Inter-Building Data Center Links

The long-reach design is suitable for connecting network rooms or data center buildings where shorter DR4 or FR4 optics may not provide sufficient distance.

Campus Data Center Networks

Universities, research institutions, and enterprise campuses can use duplex LC single-mode infrastructure to carry high-capacity 400G or aggregated 800G traffic.

Two-Way 400G Breakout Architecture

Each optical engine can be routed to a separate destination, allowing one switch OSFP cage to establish two independent 400G links.

High-Density Cloud Networks

Cloud operators can use twin-port optics to increase logical link density while retaining standard pluggable module serviceability.

Why Choose Optech?

Optech provides more than a mechanically compatible optical module. Its value comes from combining optical design with platform-focused validation.

Customers can benefit from:

• NVIDIA-compatible EEPROM coding
• Actual switch testing
• CMIS and digital diagnostic verification
• Optical power and BER testing
• Thermal performance checks
• Customized labeling and serial-number management
• Technical support for link configuration
• Taiwan-based production and supply-chain support

Compatibility results can vary by switch model, firmware version, airflow direction, port mode, and network protocol. Optech recommends confirming these parameters before final product configuration.

 

FAQ

1. What is the NVIDIA MMS4X90-NR?

MMS4X90-NR is an NVIDIA 800Gb/s twin-port OSFP transceiver containing two 400G LR4 optical engines. It uses two duplex LC connectors, single-mode fiber, 100G-PAM4 signaling, and a 1310nm CWDM wavelength grid.

2. Is OSFP-800G-2LR4 the same as 2xLR4?

Yes. In this context, OSFP-800G-2LR4 generally describes an 800G twin-port module containing two 400G LR4 optical engines. The more technically explicit notation is OSFP-800G-2xLR4.

3. What is the maximum transmission distance?

NVIDIA’s ordering description for MMS4X90-NR lists a maximum reach of up to 10km over single-mode fiber. Actual reach depends on the ordered product variant, optical link budget, connector loss, patch panels, and fiber condition.

4. What connectors does the module use?

It uses two duplex LC optical connectors. Each connector carries one independent 400G LR4 link.

5. Can it be used with the NVIDIA SN5600?

The module category is designed for Spectrum-4 air-cooled switch connectivity. The SN5600 is a Spectrum-4 Ethernet switch with 64 OSFP 800GbE ports and support for up to 128 400GbE logical links. Final compatibility should be validated against the exact switch firmware and port configuration.

6. Can it be used with the NVIDIA QM9700?

The QM9700 uses 32 twin-port OSFP interfaces to provide 64 NDR 400Gb/s InfiniBand ports. However, Ethernet and InfiniBand operation may require different module firmware and coding. Compatibility should therefore be confirmed for the specific QM9700 software and protocol environment.

7. What is the difference between the QM9700 and SN5600?

The QM9700 is a Quantum-2 NDR InfiniBand switch with 64 400Gb/s ports, while the SN5600 is a Spectrum-4 Ethernet switch with 64 800GbE OSFP ports that can be split into as many as 128 400GbE interfaces.

8. Why use LR4 instead of DR4?

LR4 uses wavelength multiplexing over duplex single-mode fiber and is better suited to longer-distance links and existing LC structured cabling. DR4 uses parallel single-mode fibers through an MPO connector and is generally used for shorter data center reaches.

9. Can the two 400G ports connect to different switches?

The twin-port architecture provides two independent 400G optical engines. Subject to switch configuration and firmware support, each LC link can be routed independently to a different destination.

10. Does Optech test modules on actual NVIDIA switches?

Optech’s compatibility process can include module recognition, link establishment, optical power, BER, CMIS diagnostics, alarms, and platform-specific testing. The provided image shows an 800G optical link connected in an NVIDIA SN5600 switch environment.

Conclusion

The OSFP-800G-2xLR4 architecture provides a practical way to combine two long-reach 400G optical links in one high-density OSFP module.

Based on the NVIDIA MMS4X90-NR architecture, the solution uses two duplex LC interfaces, single-mode fiber, CWDM wavelength multiplexing, and 100G-PAM4 signaling to support demanding AI, HPC, data center, and long-reach switch interconnect applications.

For customers building networks around the NVIDIA Spectrum-4 SN5600 or evaluating optical connectivity for NVIDIA Quantum-2 QM9700 environments, Optech offers compatibility-focused module development, platform testing, and Taiwan-based technical support.