100gb DAC cable between 40G devices ?

[from88]

Hello,

Could someone assure me that I can use this type of DAC cable: QSFP-100G-CU1M for establishing a 40G connection ? Thanks

[Reza Sharifi]

Hi,

For what type of switches?

HTH

[from88]

Actually its between Nexus 6k and NCS 5501-SE.

[Reza Sharifi]

And what is the distance between the 2 devices?

[Reza Sharifi]

If it is between 2 40G devices, I would use the 40Gig DAC cable.

https://www.fs.com/products/39663.html

1m (3ft) HW QSFP-40G-CU1M Compatible 40G QSFP+ Passive Direct Attach Copper Cable

HTH

[from88]

thanks, it seems that the main question is if the mentioned CISCO 100G QSFP28 cables supports running in QSFP+ mode. Seems like some supports (as it already working in Some 9k Nexuses in 40G mode).