StarTech.com Cisco QSFP-H40G-ACU10M Compatible 10m 40G QSFP+ to QSFP+ Direct Attach Cable Twinax - 40GbE QSFP+ Copper DAC 40 Gbps Low Power Active Transceiver Module DAC Firepower ASR1000 ASR9000

Product Overview

AI-generated summary

If you’ve got a Cisco 40G QSFP+ port on an ASR-type platform and you want a short, simple copper link, this kind of direct attach DAC cable is usually the best value. At £112.46 ex-VAT for a 10m run, it’s priced like a “buy it once and forget it” solution—especially for rack-to-rack or within the same row where you’re not hunting for long reach. Realistically, DACs are also easier to manage than fibre: less faffing with optics, lower ongoing hassle, and usually good power efficiency for active copper links.

That said, I wouldn’t buy it if you’re expecting it to be universally painless across every mix of hardware or if you need maximum compatibility certainty. DAC “compatibility” can be picky depending on exact Cisco line cards/firmware and whether the device is strict about transceiver identification. Also, 10m is fine for structured cabling constraints, but if your path might exceed that comfortably—or you’re uncertain about cable routing—don’t gamble; get the run right first. Who should buy? Teams with known working Cisco 40G QSFP+ endpoints, stable link requirements, and a clear 10m route. Who shouldn’t? Anyone troubleshooting optics/port compatibility already, or anyone trying to standardise a fleet without validating part numbers against their specific equipment.