The 400G 100G-PAM4 OSFP and QSFP112 optical modules from NVIDIA provide a high-speed, reliable solution for switch connectivity. This article will detail the verification process of this optical module on the switch and its main features.

I. Main features of the product

1、Dual-port design:

OSFP single-mode optical module: It contains two complete multi-mode or single-mode optical engines, and each outlet is connected to two 4-channel MP0-12/APC optical connectors to form a dual-port structure.

Connection Mode: Dual-port optical modules can be directly interconnected to form an 800Gb/s link; they can also be connected to two or four 400G QSFP112 or OSFP optical modules via two straight cables or 1:2 split fiber optic cables to form two 400G or four 200Gb/s links.  

2. Flexible connection combinations:

Combination of OSFP and QSFP112: The dual-port OSFP transceiver can connect two or four OSFPs and/or QSFP112s at the same time because they have the same internal structure.

Uniform fiber type: The fiber type (pass-through or splitter) of the dual-port transceivers must be the same to ensure that the switch and transceiver combination operates properly in 2x400G or 4x200G split mode.

3. Transmission distance and optics type:

Multimode optical modules up to 50 m and singlemode optical modules up to 100 m, 500 m and 2 km are available for long link lengths between switches. The length selected is related not only to optical capability, but also to minimizing overall link latency, including switch buffer timing, optical latency and capability, and adapter timing. A 2xFR4 2km version using two LC duplex fiber connectors is also available.

II.Optical Module Type Terminology

1. Dual-port OSFP:

2x SR4: Short-range 4-channel multimode optics, 800Gb/s, maximum transmission distance 50 meters.

2x DR4: Data center 8-channel single-mode optics, 800Gb/s, maximum transmission distance 100m and 500m.

2x FR4: Long distance 4-channel single-mode optics, 800Gb/s, maximum transmission distance 2km.

2x Single-port OSFP or QSFP112:

SR4: Short distance 4-channel multimode optics, 400Gb/s, maximum transmission distance 50 meters.

DR4: Data center 4-channel single-mode optics, 400Gb/s, maximum transmission distance 100m and 500m.

FR4: Long distance 4-channel single-mode optics, 400Gb/s, maximum transmission distance 2km (not supplied).

III. Product Performance Characteristics

Heat dissipation and energy efficiency:

Dual-port OSFP: Uses 8 electrical pins connected straight through to the switch with additional cooling on top for air-cooled switches.

Power Consumption: Transceiver power consumption is 15-17W, heat dissipation is via a heat sink on top of the connector.

Compatibility and Configuration: The dual-port optical module supports two straight fiber cables with two 400G transceivers, two 1:2 splitter fiber cables to support four transceiver ends, and two sets of fibers (2 channels) at the end of 1:2 splitter fibers for a rate of 200Gb/s when used with 400Gb/s transceivers.

Fourth, application scenarios and considerations

400G InfiniBand and Spectrum-4 SN5600 Ethernet switches: with fin-top, dual-port, 2x400G OSFP optical modules.

Caveat: 400G transceivers do not support downconversion to 50G-PAM4 to achieve 200G rates, and 200G transceivers are not available.

NVIDIA's 400G 100G-PAM4 OSFP and QSFP 112 optical modules in switches demonstrate superior performance and flexible connectivity options, providing an efficient and reliable solution for data centers and high-performance computing.

Source: LinkX User Guide for 400Gbps 100G-PAM4 OSFP & QSFP112-basedCables and Transceivers