1.6T High-Speed Optical Interconnect for InfiniBand XDR B300 AI Clusters

The next generation of AI infrastructure is pushing network performance far beyond traditional data center requirements. As GPU clusters scale to support larger models, distributed training, and increasingly communication-intensive workloads, the optical interconnect must deliver not only higher bandwidth, but also ultra-low latency, low bit error rates, predictable stability, and reliable interoperability.

NVIDIA Quantum-X800 is designed around 800Gb/s end-to-end InfiniBand XDR connectivity and is purpose-built for large-scale AI workloads. NVIDIA identifies Q3400, Q3200, ConnectX-8 SuperNICs, XDR cables, and transceivers as core components of the Quantum-X800 platform.

For these next-generation environments, Optech provides 1.6T OSFP224 optical transceiver solutions engineered for InfiniBand XDR and B300 AI cluster connectivity.

The key Optech products include:

• 1.6T OSFP224 DR8 / 2xDR4 — compatible with NVIDIA MMS4A00-XM
• 1.6T OSFP224 2xFR4 — compatible with NVIDIA MMS4A50-XM
• Short-to-medium reach and extended-reach single-mode solutions
• Taiwan manufacturing and TAA options for eligible procurement projects

Optech focuses on three critical requirements for AI optical interconnects:

Ultra-Low Latency & Low BER
High Stability
Platform Validation for Reliable Deployment

Why 1.6T Optics Matter for B300 AI Clusters

NVIDIA DGX B300 systems are designed for demanding AI training and inference workloads. NVIDIA's current DGX B300 specifications include eight Blackwell Ultra GPUs and eight OSFP ports serving eight single-port ConnectX-8 adapters, each supporting up to 800Gb/s InfiniBand or Ethernet connectivity.

At the fabric level, NVIDIA's B300 XDR SuperPOD reference architecture uses Quantum-X800 Q3400 switches for both compute leaf and spine layers. A representative 576-node design includes 64 Q3400 compute leaf switches and 36 Q3400 compute spine switches, along with thousands of twin-port OSFP optical transceivers.

This is where 1.6T twin-port optics become especially important.

Instead of treating a 1.6T module simply as “twice the speed of 800G,” the architecture allows one physical OSFP cage to serve two independent 800Gb/s XDR optical engines.

That enables:

• Higher switch port density
• Efficient leaf-to-spine connectivity
• Better use of physical OSFP cages
• Reduced network cabling complexity
• Scalable GPU cluster expansion
• High-bandwidth communication between AI compute domains

NVIDIA InfiniBand XDR: Built for 800Gb/s AI Networking

NVIDIA describes Quantum-X800 as the next generation of Quantum InfiniBand, providing 800Gb/s end-to-end connectivity with ultra-low latency for training and deploying trillion-parameter-scale AI models.

The current Q3400-RA platform provides 144 XDR 800Gb/s ports through 72 OSFP cages, delivering up to 115.2 Tb/s switching throughput. NVIDIA's current documentation identifies these XDR switches as based on the Quantum-3 switch ASIC and 200Gb/s-per-lane SerDes technology.

For optical interconnect suppliers, this transition introduces much tighter requirements around:

• 200G PAM4 electrical lanes
• Signal integrity
• FEC behavior
• BER performance
• Thermal control
• Module management
• Port splitting
• Firmware compatibility
• Stable operation across thousands of links

At AI cluster scale, even a small percentage of unstable optical links can create significant troubleshooting and operational overhead.

This is why Optech emphasizes validation and link quality—not bandwidth alone.

Optech 1.6T OSFP224 DR8 / 2xDR4 Compatible with NVIDIA MMS4A00-XM

One of Optech's core 1.6T products is the:

Optech P/N: OPNR-SX5-13-CBN
Model: 1.6T OSFP224 DR8 / 2xDR4
Compatible with: NVIDIA MMS4A00-XM / 980-9IAH1-00XM00

Optech's current product portfolio lists this module as a 1.6T OSFP224 DR8, operating at 1310nm over single-mode fiber with dual MPO-12/APC optical interfaces and reach up to 500 meters.

NVIDIA describes the MMS4A00 architecture as a 1600Gb/s 2xDR4 twin-port OSFP with:

• Eight electrical lanes of 200G PAM4
• Two independent 800G DR4 optical engines
• Two MPO-12/APC connectors
• 1310nm single-mode optics
• Up to 500m reach
• Support for XDR 800Gb/s InfiniBand

Two Independent 800G Optical Engines

The key advantage is the twin-port architecture.

One 1.6T OSFP module contains:

2 × 800G DR4 optical interfaces

Each engine can operate independently, allowing one physical OSFP cage to provide two 800G XDR optical connections.

NVIDIA specifically notes that this architecture allows a 72-cage Q3400 switch to provide 144 ports of 800Gb/s connectivity.

This makes the product highly relevant for:

• B300 AI training clusters
• Quantum-X800 leaf-to-spine fabrics
• GPU scale-out networking
• High-density AI compute fabrics
• HPC clusters
• Large-scale InfiniBand networks

Why MPO-12/APC Matters at 1.6T

The MMS4A00 architecture uses two MPO-12/APC connectors in one twin-port OSFP module.

Although each MPO-12 has 12 fiber positions, NVIDIA specifies that eight fibers are used for each optical engine—four transmit and four receive fibers.

The APC optical interface is designed to minimize back reflection, which becomes increasingly important as lane speeds rise to 200G PAM4.

For high-density AI networks, this parallel single-mode architecture is particularly attractive for:

• Switch-to-switch links
• Leaf-to-spine connections
• Up to 500m data center reach
• High-fiber-density structured cabling

Optech 1.6T OSFP224 2xFR4 Compatible with NVIDIA MMS4A50-XM

For applications that require substantially longer reach, Optech also offers:

Optech P/N: OPNR-S02-13-CB2
Model: 1.6T OSFP224 2xFR4
Compatible with: NVIDIA MMS4A50-XM / 980-9IAS0-00XM00

Optech's product page lists the module with:

• 1.6Tb/s aggregate capacity
• 1310nm single-mode optics
• Dual duplex LC interfaces
• Up to 2km reach
• 0°C to 70°C operating temperature
• NVIDIA MMS4A50-XM compatibility

Compared with DR8 / 2xDR4, the 2xFR4 architecture addresses a different physical network requirement.

When to Choose 2xFR4

2xFR4 is especially useful when the network must extend beyond the typical 500m DR-class reach.

Typical use cases include:

• Large data center halls
• Campus AI infrastructure
• Inter-building connections
• Switch-to-switch links up to 2km
• Existing duplex LC single-mode cabling
• Distributed HPC facilities

Instead of parallel fibers, FR4 uses wavelength multiplexing, allowing each 800G optical engine to operate through a duplex LC fiber pair.

For customers with existing LC structured cabling, this can significantly simplify deployment.

DR8 / 2xDR4 vs 2xFR4: Which One Should You Choose?

The two Optech 1.6T products address different AI infrastructure needs.

Optech product specifications support these two reach and connector profiles.

The decision therefore depends less on raw bandwidth—both are 1.6T—and more on:

• Link distance
• Existing fiber infrastructure
• Fiber-count requirements
• Patch-panel architecture
• Switch topology
• Expansion strategy

Ultra-Low Latency & Low BER: Why They Matter in AI Fabrics

An AI network is not simply moving files from one server to another.

During distributed training, thousands of GPU processes may need to exchange data and synchronize repeatedly. Network behavior can therefore influence overall job completion time and GPU utilization.

NVIDIA describes InfiniBand XDR as providing 800Gb/s per direction with extremely low port-to-port latency.

At the optical module level, Optech's engineering focus is therefore built around minimizing link instability and maintaining signal integrity.

For project qualification, validation can include:

• BER verification
• FEC monitoring
• Transmit optical power
• Receive optical power
• Lane-level performance
• Module temperature
• Voltage monitoring
• Alarm thresholds
• CMIS diagnostics
• Link-up consistency
• Long-duration stability testing

The objective is simple:

High bandwidth is valuable only when the link remains stable.

High Stability for Large-Scale B300 Deployments

A small cluster may contain dozens of optical links.

A SuperPOD-scale AI fabric may contain thousands.

NVIDIA's representative B300 XDR SuperPOD architecture illustrates this scale clearly: its compute fabric uses thousands of twin-port OSFP optics between DGX systems, leaf switches, and spine switches.

At that scale, optical stability directly affects:

• Installation time
• Troubleshooting workload
• Network availability
• GPU utilization
• Maintenance cost
• Spare-part requirements

Optech therefore positions its 1.6T portfolio around repeatable production quality and platform-oriented validation, rather than treating every module as a standalone optical component.

Fully Validated for Deployment Confidence

Optech's approach to 1.6T products focuses on validating the optical module as part of a complete system.

Depending on the project, qualification can cover:

• Module EEPROM recognition
• Host firmware compatibility
• CMIS communication
• Link establishment
• Optical power
• BER
• FEC
• Lane operation
• Temperature performance
• Diagnostic reporting
• Long-term link stability

Optech currently lists its 1.6T OSFP224 portfolio as compatible with NVIDIA MMS4A00-XM and MMS4A50-XM, while the company's 2xFR4 product materials also describe validation with NVIDIA QM3400 systems.

For production projects, the exact qualification configuration should still be confirmed using the customer's:

• Switch model
• Firmware version
• Air-cooled or liquid-cooled system
• InfiniBand configuration
• Optical reach
• Fiber type
• Network topology

This allows the module configuration to be matched to the real deployment rather than relying on a generic compatibility profile.

Built for NVIDIA Quantum-X800 AI Infrastructure

The 1.6T twin-port OSFP architecture aligns naturally with NVIDIA Quantum-X800.

NVIDIA's current XDR switch architecture uses 72 physical OSFP cages on the Q3400 to create 144 × 800Gb/s XDR ports.

Combined with ConnectX-8 SuperNICs capable of 800Gb/s InfiniBand operation, this provides the high-bandwidth scale-out network required by B300-class AI systems.

Optech's 1.6T optics can therefore be positioned for:

• Q3400 leaf-to-spine optical links
• B300 AI compute fabrics
• InfiniBand XDR networks
• HPC fabrics
• AI training networks
• Large GPU clusters
• Distributed AI inference platforms

Taiwan Manufacturing and TAA Options

For some AI infrastructure projects, optical performance is only one part of the procurement requirement.

Government, public-sector, research, and regulated projects may also require specific country-of-origin documentation.

Taiwan is currently listed in FAR 25.003 as a WTO Government Procurement Agreement designated country. FAR also defines a WTO GPA country end product as one manufactured in such a country or, where materials originate elsewhere, substantially transformed there into a new and different article of commerce.

Optech can therefore support Taiwan-origin / TAA options for eligible product configurations and projects.

Customers requiring TAA should specify this requirement during quotation so that Optech can confirm:

• Product configuration
• Final manufacturing location
• Country of origin
• Applicable substantial-transformation requirements
• Labeling
• Serial-number documentation
• Supporting compliance documentation

TAA status should always be confirmed at the specific product and procurement level rather than assumed solely from the supplier's headquarters.

Why Choose Optech 1.6T Optical Transceivers?

For AI infrastructure buyers, the value of a transceiver supplier extends beyond the basic module specification.

Optech provides a combination of:

• 1.6T OSFP224 product availability
• MMS4A00-XM compatible DR8 / 2xDR4
• MMS4A50-XM compatible 2xFR4
• InfiniBand XDR-focused solutions
• Ultra-low-latency-oriented design
• Low-BER qualification
• High link stability
• Compatibility validation
• Taiwan manufacturing
• TAA options
• OEM/ODM support
• Customized coding and labeling
• Serial-number management
• Sample qualification and volume production support

This makes Optech suitable for customers who need a supplier capable of supporting the entire path from initial testing to large-volume AI infrastructure deployment.

Ready for Samples and Volume Orders

Optech welcomes inquiries for both qualification samples and production quantities of its 1.6T optical transceiver portfolio.

Customers can contact Optech regarding:

• 1.6T OSFP224 DR8 / 2xDR4
• NVIDIA MMS4A00-XM compatible modules
• 1.6T OSFP224 2xFR4
• NVIDIA MMS4A50-XM compatible modules
• B300 AI cluster projects
• NVIDIA Quantum-X800 deployments
• Q3400 compatibility
• InfiniBand XDR projects
• TAA requirements
• Country-of-origin documentation
• Customized firmware
• OEM/ODM programs
• Sample testing
• Volume pricing
• Lead-time planning

Contact Optech today for samples, compatibility validation, pricing, and volume orders.

FAQ

1. What 1.6T optical transceivers does Optech offer for InfiniBand XDR?

Optech currently lists two primary OSFP224 XDR products: a 1.6T OSFP224 DR8 / 2xDR4 solution compatible with NVIDIA MMS4A00-XM and a 1.6T OSFP224 2xFR4 solution compatible with NVIDIA MMS4A50-XM.

2. Is Optech's 1.6T DR8 compatible with NVIDIA MMS4A00-XM?

Yes. Optech's current portfolio lists OPNR-SX5-13-CBN as a 1.6T OSFP224 DR8 solution compatible with NVIDIA MMS4A00-XM, ordering number 980-9IAH1-00XM00.

3. Why does NVIDIA call MMS4A00 2xDR4 instead of DR8?

NVIDIA describes MMS4A00 as a twin-port module containing two independent 800G DR4 optical engines, so “2xDR4” is the more explicit architectural description. Together the two engines contain eight optical lanes, which is why compatible products may also be marketed as DR8.

4. What is the maximum reach of the Optech MMS4A00-XM-compatible module?

Optech lists its 1.6T OSFP224 DR8 product for up to 500m over single-mode fiber, using dual MPO-12/APC interfaces. NVIDIA also specifies up to 500m for its MMS4A00 reference architecture.

5. Does Optech offer an MMS4A50-XM-compatible 1.6T module?

Yes. Optech lists OPNR-S02-13-CB2 as a 1.6T OSFP224 2xFR4 solution compatible with NVIDIA MMS4A50-XM, ordering number 980-9IAS0-00XM00.

6. What is the reach of the 1.6T OSFP224 2xFR4?

Optech specifies up to 2km over single-mode fiber using dual duplex LC interfaces.

7. Which product is better for B300 AI clusters: DR8 or 2xFR4?

For dense intra-data-center fabric links up to approximately 500m, DR8 / 2xDR4 is the natural choice. For longer switch-to-switch, campus, or inter-building links up to 2km, 2xFR4 provides greater reach and uses duplex LC cabling.

8. Why are low BER and high stability important in AI clusters?

Large AI clusters can contain thousands of optical connections. Link errors, retraining, or instability can increase retransmissions, troubleshooting, and job disruption. Optech therefore includes BER, optical power, diagnostics, FEC behavior, and link stability among the relevant qualification items for high-speed modules.

9. Are these modules designed for NVIDIA Quantum-X800?

The MMS4A00 architecture supports XDR 800Gb/s InfiniBand, and NVIDIA's Quantum-X800 platform includes Q3400/Q3200 switches, ConnectX-8 SuperNICs, and XDR transceivers. Optech positions its compatible 1.6T OSFP224 portfolio for these next-generation InfiniBand environments.

10. Is B300 actually used with InfiniBand XDR?

Yes. NVIDIA publishes a DGX B300 SuperPOD reference architecture using Quantum-X800 XDR Q3400 switches in the compute leaf and spine layers.

11. Are Optech 1.6T modules TAA compliant?

Optech can provide Taiwan-origin/TAA options for eligible product configurations. Taiwan is listed as a WTO GPA designated country under FAR 25.003, but final TAA qualification must be determined for the specific product, manufacturing process, and procurement requirement.

12. Can customers order samples before volume deployment?

Yes. Optech welcomes sample qualification and volume-order inquiries. Customers should provide the target switch or adapter, firmware version, topology, optical reach, quantity, thermal environment, and any TAA or country-of-origin requirements so the appropriate configuration can be prepared.

Conclusion

As B300 AI clusters move toward InfiniBand XDR and 800Gb/s end-to-end networking, optical interconnect quality becomes increasingly important.

Optech's 1.6T OSFP224 portfolio addresses both high-density and longer-reach deployment scenarios:

1.6T OSFP224 DR8 / 2xDR4 — compatible with NVIDIA MMS4A00-XM — up to 500m

and

1.6T OSFP224 2xFR4 — compatible with NVIDIA MMS4A50-XM — up to 2km

With an engineering focus on ultra-low latency, low BER, high stability, platform validation, Taiwan manufacturing, and TAA options, Optech provides a practical optical interconnect solution for next-generation B300, Quantum-X800, AI, and HPC network deployments.

Optech welcomes sample requests, qualification projects, and volume orders for 1.6T OSFP224 optical transceivers.