Hello In my opinion the "nice" way of breaking out QSFP into 10G is something like this: https://www.fs.com/de-en/products/43552.html 40GBASE-PLR4 to 10GBASE-LR Breakout Panel 1U Rack-Mount, 24x LC Quad, 12x MTP Elite (0.35dB IL), Single Mode You connect your QSFP module using a MTP cable to the breakout panel. That particular panel will accept up to 12x MTP connections (12 QSFP ports) which equals 48x 10G LR 10 km single mode. If you don't need quite that many breakouts this solution is also available in smaller cassettes: https://www.fs.com/de-en/products/68401.html MTP-8 to 4x LC Duplex, 8 Fibres OS2 Single Mode FHD MTP Cassette That will terminate one MTP cable (1 QSFP port). I prefer the panel solution over breakout cables because the later assumes all the connections are going the same place. Also the panel solution will appear as an extension of the switch or router. Mentally it is simply extra ports on a separate panel. Regards, Baldur