1. What Is the Mellanox MMA4Z00-NS 800G OSFP SR8 Transceiver

The Mellanox MMA4Z00-NS (also called NVIDIA MMA4Z00-NS) is a high-performance 800G twin-port OSFP transceiver built for InfiniBand NDR and Ethernet networks.It can be viewed as two independent 400G transceivers packaged in a single small OSFP module, together providing 800 Gbps of bandwidth. It utilizes an 850nm wavelength and advanced 100G-PAM4 modulation technology to transmit eight optical signals simultaneously. This enables it to support dual 400Gb/s ports (SR8) via multimode fiber (MMF) – a standard fiber type commonly used for short-distance connections within most data centers.

This transceiver is at the heart of NVIDIA’s end-to-end networking ecosystem. It meets all key industry standards — including OSFP MSA, CMIS 5.0, IEEE 802.3ck, and InfiniBand NDR — ensuring smooth interoperability with Mellanox Quantum-2 switches, Spectrum-4 switches, and ConnectX-7 OSFP adapters. In short, it works seamlessly with NVIDIA’s entire networking family.

2. Key Features and Technical Specifications

2.1 800G Twin-Port Performance

The MMA4Z00-NS delivers 800Gbps aggregate bandwidth through two independent 400G ports (2×400G SR8). It uses 8×106.25Gbps PAM4 modulation on the electrical side and 2×4×106.25Gbps PAM4 on the optical side. This design supports AI training, HPC workloads, and high-density cloud applications.

2.2 Optical Interface & Reach

This transceiver is equipped with dual MPO-12/APC interfaces (green, for APC) and supports two configuration options:

• 2×400G direct links, or
• 2×200G connections using splitter cables

Operating at 850nm VCSEL over multimode fiber, this SR transceiver  achieves:

• 30 meters on OM3 MMF
• 50 meters on OM4 MMF

This eliminates the need for expensive single-mode fiber in short-range (≤50m) data center connections, significantly reducing cabling costs.

2.3 Power & Cooling

The MMA4Z00-NS 800G optical transceiver is designed for energy efficiency. It consumes a maximum of just 17W, drops to only 2.0W in sleep mode, and runs on a single 3.3V supply.

To fit different data center environments, the transceiver comes in two cooling variants:

• Finned-top – suitable for air-cooled systems
• Flat-top – suitable for liquid cooling systems; compatible with NVIDIA DGX H100.

2.4 Form Factor & Compliance

• Form factor: Twin-port OSFP, hot-pluggable
• Monitoring: DDM/DOM (Digital Diagnostic Monitoring)
• Safety: Class 1 laser, RoHS compliant
• Standards: OSFP MSA, CMIS 5.0, IEEE 802.3ck, InfiniBand NDR
• Operating temperature: 0°C to +70°C (commercial grade range)

3. How MMA4Z00-NS Works in InfiniBand NDR & Ethernet Networks

3.1 Integration with NVIDIA Quantum-2 & Spectrum-4 Switches

The MMA4Z00-NS is optimized for the NVIDIA networking ecosystem and works seamlessly with the following products:

• Quantum-2 InfiniBand switches (32 or 64 OSFP cages)
• Spectrum-4 Ethernet switches
• ConnectX-7 OSFP adapters

Thanks to its dual-port design, a single 32-port OSFP Quantum-2 switch can support up to 64 400G ports. This not only maximizes rack utilization but also reduces the switch hardware cost per 400G port.

3.2 2×400G Port Splitting and Link Aggregation

Each of these two MPO-12/APC connectors can operate as an independent 400G link; in addition, with splitter cables, the module also supports 2×200G connections, thus providing flexible network design options for different bandwidth requirements. The module also auto-negotiates between InfiniBand NDR and Ethernet protocols based on the connected port, so there’s no manual configuration required.

4. Key Advantages of the Twin-Port Design

4.1 Higher Port Density & Lower Switch Cost

By integrating two 400G engines into a single OSFP module, the MMA4Z00-NS doubles port density, thereby reducing the number of switches and lowering capital expenditure (CAPEX).

4.2 Reduced Cabling Cost with MMF

With support for 50m reach on OM4 MMF, the MMA4Z00-NS eliminates the need for single-mode fiber and optics in short-range top-of-rack (ToR) to leaf/spine connections. OM4 cabling is significantly less expensive than single-mode fiber, reducing overall cabling infrastructure costs.

4.3 Flexibility for Air or Liquid Cooling

The availability of both finned-top (air-cooled) and flat-top (liquid-cooled) variants allows data center operators to match the transceiver to their existing cooling strategy. This is particularly important for high-density AI clusters using NVIDIA DGX H100 systems, which often employ liquid cooling.

5. Applications and Deployment Scenarios

5.1 AI/ML Clusters & HPC Systems

The MMA4Z00-NS is ideal for connecting NVIDIA DGX H100 servers to Quantum-2 InfiniBand switches in distributed AI training and inference clusters. It also supports HPC clusters, scientific computing, and research labs requiring low-latency, high-bandwidth data transfer.

5.2 Hyperscale Cloud & Enterprise Data Centers

In hyperscale cloud environments, the transceiver is used for:

• Leaf-spine architecture uplinks
• Top-of-rack (ToR) switch-to-server connections
• Storage network links (≤50m)

Enterprise data centers benefit from its high-density 400G/800G connectivity for virtualization, big data analytics, and cloud migration projects.

5.3 Storage & Server Rack Connectivity

The MMA4Z00-NS can be deployed in server racks where short-reach, high-bandwidth connections are required between compute nodes and storage systems. Its low power consumption (≤17W) and sleep mode (2.0W) help keep operational expenses (OPEX) under control.

6. Compatibility and Ecosystem Integration

6.1 NVIDIA Quantum-2, Spectrum-4, and ConnectX-7

The MMA4Z00-NS is fully compatible with:

• Mellanox Quantum-2 switches (32/64 OSFP cages)
• Mellanox Spectrum-4 switches (32/64 OSFP cages)
• ConnectX-7 OSFP adapters (400G NICs)

This end-to-end NVIDIA compatibility ensures predictable performance, reliability, and firmware interoperability.

6.2 Third-party OSFP MSA Compliant Switches

Because the MMA4Z00-NS complies with OSFP MSA and CMIS 5.0 standards, it can also operate in third-party OSFP-enabled switches that support 400G/800G PAM4 SR8 transceivers. However, for full feature support and performance validation, NVIDIA’s own switches and adapters are recommended.

7. Monitoring, Reliability and Maintenance

7.1 DDM/DOM Real-Time Monitoring

The MMA4Z00-NS includes Digital Diagnostic Monitoring (DDM) and DOM (Diagnostic Optical Monitoring) capabilities. Network administrators can monitor real-time parameters such as:

• Temperature
• Supply voltage
• Laser bias current
• Transmit and receive optical power

This enables proactive fault detection and network maintenance.

7.2 Hot-Swappable & CMIS 5.0 Compliance

The transceiver is hot-pluggable, allowing replacement without powering down the switch. Compliance with CMIS 5.0 (Common Management Interface Specification) ensures standardized management and control across different platforms.

8. Frequently Asked Questions (FAQ)

What is the reach of MMA4Z00-NS on OM4 fiber?

A: The MMA4Z00-NS supports up to 50 meters on OM4 multimode fiber. On OM3 fiber, the maximum reach is 30 meters. Always use MPO-12/APC connectors (green) — not UPC (aqua).

Is MMA4Z00-NS compatible with InfiniBand NDR?

A: Yes. The MMA4Z00-NS natively supports InfiniBand NDR and Ethernet (IEEE 802.3ck). It auto-negotiates the protocol based on the connected switch or NIC port.

What is the difference between MMA4Z00-NS and MMA4Z00-NS400?

A: The MMA4Z00-NS is a twin-port 800G (2×400G) transceiver with dual MPO-12/APC connectors. The MMA4Z00-NS400 is a single-port 400G transceiver with one MPO-12/APC connector, designed primarily for ConnectX-7 NICs.

Can it support AI and HPC workloads?

A: Yes. The MMA4Z00-NS is specifically designed for AI training clusters, HPC systems, and hyperscale cloud data centers. It delivers the high bandwidth and low latency required for distributed AI/ML workloads.

9. Conclusion

The Mellanox MMA4Z00-NS 800G twin-port OSFP SR8 optical transceiver delivers 800Gbps aggregate bandwidth over dual MPO-12/APC connectors, supporting 50m reach on OM4 MMF. Its 2×400G design doubles port density, reduces cabling costs, and offers flexible cooling options.

Fully compliant with OSFP MSA, CMIS 5.0, and InfiniBand NDR, it integrates seamlessly with NVIDIA Quantum-2 switches, Spectrum-4 switches, and ConnectX-7 NICs. For AI, HPC, and hyperscale cloud deployments, the MMA4Z00-NS provides a future-proof, energy-efficient, and cost-effective 800G solution. If you are interested in the MMA4Z00-NS, please feel free to contact us for a quote.