Solution OSFP optical module 400G

In an OSFP optical module, "400G" refers to a total data transmission capacity of 400 gigabits per second, achieved through multiple high-speed lanes using PAM4 modulation.

What 400G Means in OSFP

The 400G designation indicates that the optical transceiver can handle 400 gigabits per second of data. OSFP (Octal Small Form-factor Pluggable) modules achieve this by using 8 electrical lanes, each operating at 50G using PAM4 modulation, which together sum to 400G total bandwidth . Some variants, like DR4, use 4 lanes at 100G each, still achieving 400G but with fewer lanes .

OSFP Form Factor Advantages

OSFP modules are slightly larger than QSFP-DD modules, which allows for better thermal management and higher power budgets (typically 8–12W for 400G, with some models up to 15W), . This makes them suitable for high-density, high-speed data center environments, including AI clusters and hyperscale networks .

Lane Architecture and Modulation

• 8×50G PAM4 lanes: Standard for most 400G OSFP modules, providing robust signal integrity and scalability .
• 4×100G PAM4 lanes: Used in 400GBASE-DR4 modules for single-mode fiber with up to 500 meters reach .
• PAM4 modulation: Pulse Amplitude Modulation with 4 levels doubles the data capacity per symbol compared to traditional NRZ signaling, enabling higher throughput without increasing the number of fibers .

Applications

400G OSFP modules are widely used for:

• Data center interconnects (TOR to spine connections)
• High-bandwidth Ethernet fabrics
• AI/ML cluster networking
• Flexible breakout configurations to 100G per lane .

Summary

In essence, 400G in an OSFP module represents the total data rate the module can transmit, achieved through multiple high-speed lanes and advanced modulation. The OSFP form factor supports this high bandwidth while providing efficient thermal management, power handling, and future scalability for next-generation networking deployments .