1.6T OSFP-RHS Optical Transceivers for High-Density Data Centers

The growth of AI training, GPU clusters, and hyperscale computing is increasing bandwidth requirements inside modern data centers. As networks transition from 800G toward 1.6T connectivity, optical transceivers must deliver higher port capacity while meeting demanding electrical, mechanical, and thermal requirements. The 1.6T OSFP-RHS optical transceiver combines high-speed optical signaling with a reduced-height heat-sink design for selected high-density network platforms.

1. What Is a 1.6T OSFP-RHS Optical Transceiver?

A 1.6T OSFP-RHS optical transceiver is a pluggable optical module designed to support an aggregate data rate of up to 1.6Tbps. It uses the OSFP1600 form factor and a reduced-height heat-sink structure intended for integration into compatible high-density systems.

The module converts high-speed electrical signals from a switch or network interface into optical signals for transmission over fiber, then converts incoming optical signals back into electrical data. This enables high-capacity connections between switches, AI computing systems, and other network infrastructure.

In a typical 1.6T implementation, eight high-speed lanes operating at approximately 200Gbps each provide the aggregate bandwidth. PAM4 modulation, digital signal processing (DSP), and forward error correction (FEC) support high-speed signal transmission and error management.

The OSFP-RHS package is particularly relevant where module height, heat-sink geometry, and the host system's cooling arrangement must be considered together. Actual compatibility depends on the target equipment's mechanical design, electrical interface, supported module power, and thermal requirements.

2. C-LIGHT 1.6T OSFP-RHS Product Overview

3. C-LIGHT 1.6T OSFP-RHS Configurations: 500m and 2km

Different data center links require different optical reaches and connector arrangements. C-LIGHT's published product table lists two OSFP-RHS configurations for single-mode fiber, providing options for shorter high-bandwidth connections and links extending to 2km.

The table reflects the configuration descriptions published on the C-LIGHT product page. Because the part names and optical-interface terminology may refer to different implementation details, customers should confirm the exact interface standard, lane mapping, connector specification, and reach in the corresponding datasheet before ordering.

500m Configuration

The listed 500m configuration is intended for single-mode links within the specified reach. Its MPO-12 connector arrangement makes fiber polarity, lane mapping, cable assembly, and connector cleanliness important during installation.

Typical design considerations include the route length, patch-panel layout, optical loss, and compatibility between the module and the switch port. The actual connection should follow the specified optical interface rather than relying on connector shape alone.

2km Configuration

The listed 2km configuration uses dual LC/APC connectivity. This connector arrangement can simplify integration into compatible structured single-mode fiber cabling, but the optical interface and connector polish must match the requirements of the selected module and fiber path.

For either configuration, confirm that both ends of the link use compatible optical interfaces. Two modules with the same nominal bandwidth may not interoperate if their optical standards, wavelengths, lane arrangements, or electrical host interfaces differ.

4. Reduced-Height Heat-Sink Design

Thermal management is a major consideration in high-speed optical modules. As data rates increase, the electrical interface, DSP, optical engine, and supporting circuits must operate within specified temperature and power limits. The host system must remove the heat generated by these components while maintaining stable operation.

OSFP-RHS uses a reduced-height heat-sink structure. This package design is intended to accommodate selected high-density system layouts where the module's physical envelope and thermal interface must work with the host's cooling architecture.

The heat-sink structure is only one element of the thermal path. Heat must move from internal components through the module's thermal structures and into the surrounding cooling environment. Performance depends on the module's actual power dissipation, thermal resistance, contact conditions, airflow or cold-plate design, and ambient temperature.

5. OSFP-RHS for Cold-Plate and Liquid-Cooling Architectures

AI data centers increasingly evaluate liquid cooling as computing density rises. In these systems, optical transceiver thermal integration must be coordinated with the mechanical and cooling design of the switch, server, or accelerator platform.

C-LIGHT describes its 1.6T OSFP-RHS family as designed for high thermal-dissipation requirements, including integration with compatible cold plates or liquid-cooling systems. Suitability for a specific platform still depends on the product's mechanical dimensions, thermal contact arrangement, power limits, and system qualification.

Cold-Plate Integration

A cold plate removes heat through a controlled thermal interface connected to a liquid-cooling loop. For an optical module, integration requires the correct package geometry, appropriate thermal contact, and a host design that maintains the required mechanical and operating conditions.

Before deployment, engineers should confirm the cold plate's contact area, clearance, installation method, permitted mechanical loading, and thermal performance. The module and cooling hardware should be qualified as a combined configuration.

Air-Cooled Systems

Air-cooled platforms depend on chassis airflow, fan performance, pressure, and the arrangement of neighboring modules. A reduced-height heat sink must be evaluated within the intended host design rather than in isolation.

High-density installations should be tested with the expected number of active ports and the actual operating workload. A module's temperature in a lightly populated test system may not represent its behavior in a fully populated switch.

Immersion Cooling

Direct liquid immersion is different from cold-plate cooling. It exposes equipment to a cooling liquid and therefore requires explicit material, sealing, connector, and operating-environment qualification.

Do not assume that an OSFP-RHS module is suitable for direct immersion simply because it has a reduced-height heat sink or is described as compatible with liquid cooling. Confirm the specific cooling method approved for the exact product and target system.

6. 1.6T OSFP-RHS in AI Data Center Networks

GPU Cluster Interconnects

AI training workloads distribute computation across large numbers of accelerators. Data exchange between these devices can generate sustained network traffic, especially during collective operations and model synchronization. Higher-capacity optical links help scale bandwidth between supported switches and network endpoints.

A 1.6T module can provide more bandwidth per optical port than an 800G module, but the overall benefit depends on switch capacity, network topology, traffic patterns, and the ability of connected systems to use the additional throughput.

Hyperscale Cloud Infrastructure

Cloud data centers must connect compute, storage, and network resources while managing increasing port density and power requirements. Higher-rate optical modules can increase bandwidth per connection and help network designers plan future capacity expansion.

Deployment planning should include the supported host interface, optical reach, cabling arrangement, power budget, and maintenance procedures. Module selection should align with the network's actual capacity requirements rather than data rate alone.

High-Performance Computing

HPC environments often require high-throughput connections between compute nodes and switching systems. A 1.6T optical interface can be considered where supported network equipment requires greater per-port bandwidth, subject to the applicable Ethernet or other interface specifications.

High-Density Switching

In high-density switches, thermal design and serviceability are closely connected. The module must fit the cage and cooling envelope, remain within its operating limits, and support the required optical interface. Port density, airflow, cable routing, and module replacement access should be considered during system design.

7. 1.6T OSFP-RHS Compared with 800G Optical Transceivers

Moving from 800G to 1.6T increases nominal bandwidth per port, but it also raises requirements for electrical signaling, signal integrity, thermal integration, and host support.

C-LIGHT provides adjacent-generation products for network designs at different bandwidth levels, including 800G OSFP and 800G QSFP-DD. These options may be relevant to existing network layers or staged capacity upgrades.

Physical fit does not guarantee interoperability. A 1.6T OSFP-RHS module should only be installed in equipment that supports the relevant OSFP1600 interface, module power, management requirements, and thermal design.

8. Signal Integrity, DSP, and FEC

High-speed optical connectivity depends on reliable signal transmission across both the electrical host channel and the optical fiber link. At 200G per lane, electrical channel loss, noise, reflections, and implementation tolerances become important factors in system design.

PAM4 Signaling

PAM4 uses four signal levels to represent two bits per symbol. This increases the number of bits carried per symbol compared with NRZ, helping support higher data rates within practical signaling constraints. The smaller separation between PAM4 levels also makes signal quality and noise control more demanding.

Digital Signal Processing

DSP supports signal conditioning and recovery to compensate for channel impairments. Its implementation must match the electrical and optical interfaces used by the module and host system.

Forward Error Correction

FEC adds redundancy that allows a receiver to detect and correct certain transmission errors. Its supported mode and operation depend on the interface specification and host implementation. Both ends of the link must operate according to the applicable standard.

For C-LIGHT's 1.6T OSFP-RHS, the product description identifies integrated DSP and FEC. Exact compliance requirements and configuration details should be confirmed in the datasheet for the selected part number.

9. Power Budget and Thermal Validation

High-speed optical modules should be evaluated using both their specified electrical power consumption and the cooling capability of the host. A module's actual temperature depends on the heat it generates and the system's ability to remove that heat.

• Module power: Verify maximum and typical power figures for the exact transceiver variant.

• Host capability: Confirm that the switch or adapter supports the module's power requirements.

• Thermal interface: Check heat-sink clearance, contact conditions, and any approved cold-plate arrangement.

• Operating environment: Confirm the specified case temperature range and cooling conditions.

• Port density: Evaluate thermal behavior with the expected number of active modules.

• Monitoring: Check supported digital diagnostics and temperature alarm behavior.

• Link stability: Validate optical power, error counters, and traffic performance under the expected workload.

Temperature monitoring is useful for identifying abnormal operating conditions, but it does not replace the manufacturer's thermal qualification or the host system's cooling requirements. Deployment tests should be performed in the intended chassis and environment.

10. Installation and Compatibility Checklist

Before deploying a 1.6T OSFP-RHS optical transceiver, confirm the complete connection design, including the host platform, optical interface, fiber route, connector assembly, and cooling environment.

For multi-vendor deployments, verify interoperability using the actual host, module, firmware, and cabling combination. The same aggregate data rate or form-factor family does not establish compatibility by itself.

11. Related C-LIGHT Optical Transceiver Products

These product families support different network design requirements. Selection should be based on the exact system specification and intended link, rather than assuming that products with similar data rates share the same form factor or cooling compatibility.

12. Frequently Asked Questions

13. Conclusion

1.6T OSFP-RHS optical transceivers address the growing bandwidth needs of AI data centers, GPU clusters, HPC networks, and hyperscale switching systems. Their high-speed signaling architecture and reduced-height heat-sink design make electrical compatibility and thermal integration important parts of deployment planning.

C-LIGHT's 1.6T OSFP-RHS product family lists single-mode optical configurations for 500m and 2km links. The 800G OSFP and 800G QSFP-DD families provide additional options for compatible network generations.

Successful deployment requires more than matching data rates. Host support, optical standards, connector mapping, fiber loss, module power, and the cooling system must all be validated against the exact product specification. Careful selection and system-level testing help establish reliable high-density optical connectivity as data center networks move toward 1.6T.