Exploring FS 800G Transceivers: Your FAQs Answered

With the rapid development of technologies such as cloud computing, the Internet of Things (IoT) and big data, there’s a growing need for network bandwidth and faster transmission speeds. The introduction of the 800G module addresses this demand for high-speed data transmission. FS 800G transceivers incorporate advanced modulation and demodulation techniques alongside high-density optoelectronic devices, enabling them to achieve higher transmission rates in a compact form factor. Here are some FAQs about FS 800G optical transceivers.

What form-factors are used for 800G transceivers?

800G transceivers share the same form factors as 400G optics, namely OSFP and QSFP-DD. FS supports both form factors.


The OSFP, or “Octal Small Form-factor Pluggable,” derives its name from its 8 electrical lanes, each modulated at 100Gb/s for a total bandwidth of 800Gb/s in 800G configurations.


The QSFP-DD, or “Quad Small Form-factor Pluggable – Double Density,” retains the QSFP form factor but adds an extra row of electrical contacts for more high-speed electrical lanes. With 8 lanes operating at 100Gb/s each, the QSFP-DD delivers a total bandwidth of 800Gb/s.

QSFP-DD and OSFP are distinct optical module packaging types. QSFP-DD, being smaller, is ideal for high-density port configurations. And OSFP consumes slightly more power compared to QSFP-DD. Additionally, QSFP-DD is fully compatible with QSFP56, QSFP28, and QSFP+, whereas OSFP is not.

For more details on the differences between 800G OSFP and QSFP-DD packaging, please refer to:800G Transceiver Overview: QSFP-DD and OSFP Packages

Can OSFPs be plugged into a QSFP-DD port, or QSFP-DD’s plugged into an OSFP port?

No. The OSFP and the QSFP-DD are two physically distinct form factors. OSFP systems require the use of OSFP optics and cables, while QSFP-DD systems necessitate QSFP-DD optics and cables.

How many electrical lanes are used by 800G transceivers?

The 800G transceivers utilise 8x electrical lanes in each direction, with 8 transmit lanes and 8 receive lanes.

What are the speed and modulation formats used by 800G OSFP/QSFP-DD modules?

As mentioned earlier, all 800G modules utilise 8x electrical lanes bidirectionally, with 8 transmit lanes and 8 receive lanes. Each lane operates at a data rate of 100G PAM4, yielding a total module bandwidth of 800Gb/s. Furthermore, the optical output of all 800G transceivers consists of 8 optical waves, each wave modulated at 100G PAM4 per lane.

What is the significance of PAM4 or NRZ modulation for electrical or optical channels?

NRZ, which stands for “Non Return to Zero,” refers to a modulation scheme used in electrical or optical data channels. It involves two permissible amplitude levels or symbols, with one level representing a digital ‘1’ and the other representing a digital ‘0’. NRZ is commonly employed for data transmission up to 25Gb/s and is the simplest method for transmitting digital data. An example of an NRZ waveform, along with an eye diagram illustrating NRZ data, is depicted below. An eye diagram provides a visual representation of a modulation scheme, with each symbol overlapping one another.

PAM4, on the other hand, stands for Pulse Amplitude Modulation – 4, with the ‘4’ signifying the number of distinct amplitude levels or symbols in the electrical or optical signal carrying digital data. In this case, each amplitude level or symbol represents two bits of digital data. Consequently, a PAM4 waveform can transmit twice as many bits as an NRZ waveform at the same symbol or “Baud” rate. The diagram below showcases a PAM4 waveform along with an eye diagram for PAM4 data.

For more information on the comparison between NRZ and PAM4, please refer to:NRZ vs. PAM4 Modulation Techniques

What is the maximum power consumption of 800G OSFP and QSFP-DD transceivers?

The power consumption of 800G transceivers varies between 13W and 18W per port. To obtain specific power consumption values for individual modules, please consult each transceiver’s datasheet.

Do FS 800G transceivers support backward compatibility?

The backward compatibility of 800G transceivers depends on the specific design and implementation. Some 800G transceivers are designed to be backwards compatible with 400G or 200G transceivers, allowing for a smooth transition and interoperability within existing networks. For example, the FS 800G OSFP SR8 transceiver supports 800G ethernet and breakout 2x 400G SR4 applications. However, it is important to check with the module manufacturer for specific compatibility details.

What standards govern 800G transceivers?

Standards for 800G transceivers, such as form factor specifications, electrical interfaces, and signalling protocols, are typically governed by industry consortiums like the IEEE (Institute of Electrical and Electronics Engineers), the OIF (Optical Internetworking Forum), and the QSFP-DD MSA (Quad Small Form Factor Pluggable – Double Density Multi-Source Agreement).

What 800G Transceivers are available from FS?

FS supports 800G optical transceivers in both OSFP and QSFP-DD form factors. The key features of an FS 800G optical module typically include supporting multiple modulation formats, high data transfer rates, low power consumption, advanced error correction mechanisms, compact form factors (e.g., QSFP-DD or OSFP), and interoperability with existing network infrastructure. The tables below summarise the 800G transceiver connectivity options supported.

QSFP-DD Part No.Product DescriptionOSFP Part No.Product Description
QDD-SR8-800GGeneric Compatible QSFP-DD 800GBASE-SR8 PAM4 850nm 50m DOM MPO-16/APC MMF Optical Transceiver ModuleOSFP-SR8-800GNVIDIA InfiniBand MMA4Z00-NS Compatible OSFP 800G SR8 PAM4 2 x SR4 850nm 50m DOM Dual MPO-12/APC NDR MMF Optical Transceiver Module, Finned Top
QDD-DR8-800GGeneric Compatible QSFP-DD 800GBASE-DR8 PAM4 1310nm 500m DOM MPO-16/APC SMF Optical Transceiver Module, Support 2 x 400G-DR4 and 8 x 100G-DROSFP-DR8-800GNVIDIA InfiniBand MMS4X00-NM Compatible OSFP 800G DR8 PAM4 2 x DR4 1310nm 500m DOM Dual MPO-12/APC NDR SMF Optical Transceiver Module, Finned Top
QDD800-PLR8-B1Generic Compatible QSFP-DD 800GBASE-PLR8 PAM4 1310nm 10km DOM MPO-16/APC SMF Optical Transceiver Module, Support 2 x 400G-PLR4 and 8 x 100G-LROSFP-2FR4-800GNVIDIA InfiniBand MMS4X50-NM Compatible OSFP 800G 2FR4 PAM4 1310nm 2km DOM Dual Duplex LC/UPC NDR SMF Optical Transceiver Module, Finned Top

What are the advantages of upgrading to 800G technology?

Moving to 800G technology offers several benefits for network infrastructure and data-intensive applications:

  1. Increased Bandwidth: 800G technology offers a significant increase in bandwidth, enabling faster and more efficient data transmission, meeting the growing demand for high-speed data transfer across various industries.
  2. Higher Data Rates: With 800G technology, data rates of up to 800Gbps can be achieved, enabling faster data processing, reduced latency, and improved overall network performance.
  3. Future-Proofing: Adopting 800G technology allows organizations to future-proof their network infrastructure, ensuring compatibility with upcoming technologies and applications.


The advent of 800G technology represents a pivotal advancement in addressing the escalating demands for network bandwidth and faster transmission speeds in our rapidly evolving digital landscape. FS 800G transceivers, with their seamless compatibility with existing network infrastructure, offer a compelling solution for organisations seeking to enhance their data transmission capabilities.

Upgrade to FS 800G optical transceivers today to experience unparalleled performance, and increased bandwidth for the challenges and opportunities of tomorrow.