Introduction to 400G OSFP and 400G QSFP-DD Transceivers

What is the Difference Between 400G OSFP and 400G QSFP-DD Transceivers ?

This article will introduce the features of each 400G OSFP and 400G QSFP-DD Transceivers and explain the major difference between them.

400G QSDFP-DD Transceivers

QSFP-DD stands for Quad Small Form Factor Pluggable Double Density. What Double Density means? What’s the difference with the QSFP and QSFP28?

The 400G QSFP-DD Transceiver follows the same port densities system as the QSFP and QSFP28, but the QSFP-DD will support eight lanes instead of four lanes for the QSFP and QSFP28, which double the density.

Each of the eight lanes will operate a data rate up to 50Gb/s providing a 400Gb/s data speed and increasing the capacity of the QSFP28 by four. The 400G QSFP-DD published that the size of the optical transceivers enables to put 36 ports in one switch slot, accumulating 14.4 Tbp/s in one slot.

More information about the 400G QSFP-DD Transceivers here.

400G QSFP-DD transceivers

400G QSFP-DD SR8 Transceivers

400G OSFP  Transceivers

OSFP stands for Octal Small Form factor Pluggable. As the QSFP-DD, the OSFP has 8 lanes supporting 50G each. The OSFP is a new pluggable form factor, which is slightly wider and deeper than the QSFP family.

Its larger size is designed for maximum thermal and electrical performance. However, it will only have 32 ports in one switch slot, giving up to 12.8 Tbp/s in one slot.

The difference between the 400G OSFP and the 400G QSFP-DD Transceivers

The great advantage of the 400G QSFP-DD transceiver is its backward compatibility with the QSFP and QSFP28. Indeed the QSFP-DD ports will also support 40G and 100G, which will facilitate and reduce the cost of the network migration toward the 400G.

The larger size of the 400G OSFP transceiver won’t enable the backward compatibility with the QSFP and QSFP28. However the OSFP MSA group says that it will be possible to build an adaptor (OSFP to QSFP) that supports other QSFP transceivers.

About Optech

Optech is a leading company in developing and manufacturing Optical Transceivers and Cables solutions for Data Centers and Telecom market. Since 2001, Optech has been offering accurate lead time and high quality products to customers.

Optech offers a broad range of networking and communication solutions in following categories: Optical Transceivers, SFP, 10G SFP+, 25G SFP28, 40G QSFP+, 100G QSFP28, 400G QSFP-DD, Direct Attach Cables (DAC), Active Optical Cables (AOC), Ethernet Media Converter, Fiber Optical Patchcord, BWDM, CWDM, DWDM Mux/Demux and Repeater products.

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