40G QSFP+ Series

The 40G QSFP+ series is the 40G family in this catalogue. Its published titles are the 40G QSFP+ SR4, 40G QSFP+ LR4 and 40G QSFP+ ER4 transceivers, together with the 25G SFP28 title, which appears on the same category page in the published catalogue and is recorded here in that place rather than moved to another family. Of those titles, only the SR4 model carries a full published specification sheet, and it has its own detail page. The LR4 and ER4 titles are listed here at series level, with no performance figures invented for them.

Forty gigabit occupies a particular place in network design. It is the natural aggregation speed above 10G access links and below 100G core links, and it suits the aggregation layer of a data centre or campus where many 10G links converge. A QSFP+ module delivers 40G through four lanes in parallel, in the same way that a QSFP28 module delivers 100G, and the two formats share the same physical approach at different speeds. Buyers moving from 10G to 40G should check the fiber plant and the patch panels as part of the project, because the multi-fiber connectors used by parallel-optics modules differ from the duplex connectors used by 10G modules.

The fully specified model in this series is the 40G QSFP+ SR4, whose detail page states a 40Gb/s rate, an 850nm wavelength, 100m and 300m reach options over multimode fiber, power consumption below 3.5W and a 0 to 70 degree Celsius operating range. Those figures belong to the SR4 model alone, with the 300m option belonging to the CSR4 model. They are not shared with the LR4 or ER4 titles in this series, and a buyer who needs figures for one of those titles should ask for them during the inquiry.

The 25G SFP28 title recorded on this category page deserves a note, because it is easy to misread. It appears in the published catalogue under the 40G category page, and this site records it there without reassigning it to another family or inventing figures for it. A buyer interested in that title should state it by name during the inquiry, so the answer can be specific to it.

Before ordering, confirm quantity, price and delivery time during the inquiry. Certificates are available upon request. If you need figures for a title in this series that has no detail page, state the title and the link it will serve.