400G OSFP and 400G QSFP-DD are the most common 400G module form factors on the market. They share several similarities, including hot-swappable form factor modules, running 8x lanes of 50G on the electrical side adopting PAM4 modulation technology, supporting high-speed 400G data rates for use in data centers, high-performance computing, and telecommunications. However, they differ in many aspects to address different needs regarding size, power consumption, thermal management, backward compatibility, etc. We’re going to discuss the differences in detail in the following parts.
Size:
In terms of size, OSFP is slightly broader and deeper than the more compact QSFP-DD, providing it with more surface area to achieve better heat dissipation capabilities. QSFP-DD shares a similar size with QSFP28, allowing QSFP-DD optics to be inserted into QSFP28 ports, which offers backward compatibility and flexibility in upgrading existing infrastructure. In contrast, OSFP’s larger form factor precludes such compatibility. Still, it enhances thermal management and supports higher power dissipation, making it suitable for high-performance applications that require robust cooling solutions.
Thermal Management Design
QSFP-DD adopts the traditional riding heat sink design, placing the heat sink on top of the module and relying heavily on the equipment’s airflow for cooling, which can limit its power handling capability in high-density environments. In contrast, OSFP employs an integrated heat sink design, allowing for a more substantial and efficient heat dissipation mechanism within the module.
This integrated approach enhances thermal performance by providing a greater surface area for heat dissipation and supporting advanced cooling technologies. It enables OSFP to manage higher power optics more effectively and maintain lower operating temperatures, resulting in better overall reliability and suitability for high-performance applications.
Backward Compatibility:
400G QSFP-DD is backward compatible with other existing QSFP derivatives transceivers, such as QSFP+, QSFP28, and QSFP56, giving it high adaptability to seamlessly integrate with the 40G/100G/200G optical transceivers. Also, it is future-proofing for the next-generation 800G QSFP-DD upgrades. Due to its backward compatibility, QSFP-DD maintains the connector contacts at a 0.8 mm pitch and incorporates additional rows of recessed contacts. In contrast, OSFP enhances density by utilizing a 0.6 mm connector contact pitch, compared to the standard 0.8 mm pitch used today. OSFP itself is not directly compatible with QSFP. A QSFP to OSFP adapter converter module is needed to connect the OSFP port to QSFP.
Power Consumption:
Due to its larger size and better thermal management and cooling design, the OSFP can handle a higher power consumption level, typically 15W. OSFP is ideal for more power-mission applications, such as high-performance computing, long-haul telecommunications, and data centers with demanding power requirements. In contrast, QSFP-DD has a lower power upper threshold, theoretically 12W. This lower power handling capability makes QSFP-DD well-suited for applications where power efficiency and lower heat dissipation are prioritized, such as short-reach interconnects and applications with strict power constraints.
Application Technology
QSFP-DD is primarily utilized for Ethernet applications, providing high-speed connectivity for data centers, enterprise networks, and telecommunications. Conversely, OSFP supports Ethernet and extends its compatibility to other high-speed networking protocols, including Nvidia Infiniband. Broader technology capability renders OSFP more versatile, enabling its deployment in a wider array of high-performance computing (HPC) environments and data-intensive applications. Furthermore, OSFP’s enhanced power handling capability and exceptional thermal management design make it suitable for demanding applications in HPC clusters, supercomputing, and artificial intelligence (AI) systems, where high bandwidth, low latency, and efficient cooling are crucial for optimal performance.
Therefore, while QSFP-DD is predominantly used in Ethernet-based networking environments, OSFP’s compatibility with a broader range of protocols, including Nvidia Infiniband, positions it as a versatile and high-performance solution for advanced networking applications across various industries.
| Parameter | QSFP-DD | OSFP |
| Size | 18.35mm× 8.5mm x 89.4mm | 22.58 mm × 13mm x100.4 |
| Backward Compatibility with QSFPxx | Yes | Need QSFP to OSFP adapter |
| Power Consumption | ≤12W | ≤15W |
| Thermal Management | riding heat sink | integrated heat sink |
| 800G Adoption | Yes | Yes |
| Port Density in 1U | 36 | 36 |
| MSA | QSFP-DD MSA | OSFP MSA |
| Application | Ethernet | Ethernet, Nvidia Infiniband |
Conclusion
While both 400G QSFP-DD and 400G OSFP transceivers offer significant advantages for high-speed networking, their differences in size, power consumption, thermal management, and application technology cater to different needs. QSFP-DD’s backward compatibility and compact size make it ideal for Ethernet applications and seamless upgrades in existing infrastructures. Meanwhile, OSFP’s superior thermal management and broader protocol compatibility, including Nvidia Infiniband, make it a versatile solution for high-performance computing environments and data-intensive applications. Choosing the right form factor depends on the specific requirements of the network and the applications it supports.
FAQs About Walsun 400G Transceivers
Q: What are the benefits that Walsun 400G transceivers can offer?
A: Walsun 400G transceivers help cloud operators, service providers, and enterprises to achieve higher bandwidth at lower cost and power per gigabit. Key benefits of Walsun 400G transceivers include:
- With both OSFP and QSFP-DD form factors to meet your diverse needs of ramping up to 400G transmission.
- SiPh-based technology used on some Walsun 400G transceivers for lower power & cost and higher density.
- Compliant with QSFP-DD MSA and IEEE 802.3bs, and tested in host devices for proven interoperability, superior performance, quality, and reliability.
- Compatible with mainstream brands such as Cisco, Juniper, Arista, Dell, Mellanox, etc.
- Simplify your network by reducing the number of optical fiber links, connectors and patch panels by a factor of 4.
Q: What are the application scenarios of Walsun 400G transceivers?
A: 400G QSFP-DD transceiver modules are the backbone of high-performance 400G networks. Walsun 400G transceivers can be used in various scenarios. Generally speaking, it depends on the connection distance you want to cover. For example, you can use 400G DAC and AOC cables for short-reach connections between ToR switch and server. For 2km to 10km data center interconnection connections, QSFP-DD FR4 or LR4 modules are better high-quality and economical choices.
Q: What quality certifications do you have for your 400G transceivers?
A: Walsun 400G transceivers accord with a range of certifications for optical transceivers including ISO 9001:2015, RoHS, REACH, CB, RCM, FCC, and Russian TR CU certificate (EAC Certificate). Rest assured that our products will meet essential quality and safety requirements.
Q: Are Walsun 400G transceivers compatible with Cisco or Juniper brands?
A: Many of our 400G transceiver modules are compatible with Cisco, Juniper, Arista, Dell, Mellanox, etc. You can always ask for a compatibility test before the purchase to check whether our transceiver is compatible with your devices. If you’re deploying a larger network or upgrading your current data center architecture, compatible transceiver modules may come in handy as they can be immediately installed without compatibility problems and fit right into your data center infrastructure.
Q: Can I plug Walsun OSFP module into a 400G QSFP-DD port, or Walsun QSFP-DD module into an OSFP port?
A: No. OSFP and QSFP-DD are two physically distinct form factors. If you have an OSFP system, then Walsun 400G OSFP modules must be used. If you have a QSFP-DD system, then Walsun 400G QSFP-DD modules must be used.
Q: Can Walsun 100G QSFP module be plugged into a 400G QSFP-DD port?
A: Sì, un modulo di transceiver 40/100GQSFP può essere inserito in una porta QSFP-DD in quanto QSFP-DD è retro-compatibile con i moduli QSFP, QSFP+ e QSFP28. Quando si utilizza un modulo QSFP in una porta QSFP-DD 400G, la porta QSFP-DD deve essere configurata per la velocità dati di100G.
Q: Cosa devo fare se non so quale modulo è il più adatto per me?
A: Our dedicated customer support offers 24/7 technical assistance. If you have any questions about our transceiver modules, such as how to select the right 400G optical transceiver for your switches, how to choose between different form factors, what to do when typical technical glitches occur, or how to place an order, don’t hesitate to contact our tech support.
Q: Can I return the product or get a refund?
A: Walsun wants you to be thrilled with our 400G transceiver modules. However, if you need to return an item or ask to get a refund, we’re here to help. For all 400G transceiver modules, DAC & AOC cables, and breakout cables, you have 30 calendar days to return an item from the date you received it, which means the request must be submitted within the return/exchange window. Refunds will be processed after Walsun receives and inspects the returned items.
Q: How long is the warranty period for Walsun 400G transceivers?
A: We offer you a warranty period of five years for the purchase of 400G transceiver modules, DAC & AOC cables, and breakout cables. The warranty covers only defects arising under normal use and does not include malfunctions or failures resulting from misuse, abuse, neglect, alteration, problems with electrical power, usage not in accordance with product instructions, acts of nature, or improper installation or improper operation or repairs made by anyone other than Walsun or an Walsun authorized service provider. Please check Walsun Products Warranty for detailed info.
If you have any questions about Walsun 400G transceiver modules, you can always Contact Us for assistance.
