StarTech.com Cisco GLC-SX-MMD Compatible SFP Transceiver Module - 1000BASE-SX~Cisco GLC-SX-MMD Compatible SFP Module - 1000BASE-SX - 1GbE Multimode Fiber MMF Optic Transceiver - 1GE Gigabit Ethernet SFP - LC 550m - 850nm - DDM Cisco Firepower, ASR920, IE2000

Product Overview

AI-generated summary

For ~£38 ex-VAT, this is the kind of SFP you buy when you need a straightforward, “get the link back up” replacement for a Cisco-compatible 1000BASE-SX multimode port. If your environment is mostly LC multimode fibre and you’re not pushing the absolute limits of optics every day, it tends to be good value—StarTech compatibles are usually reliable enough for day-to-day network work, and the DDM support is helpful for basic monitoring (so you’re not flying blind).

I’d buy it for: smaller sites, spare optics in the comms cupboard, or budget-conscious refreshes where you just need correct operation on Cisco gear that expects that module type. I’d avoid it if you have strict optics policies, lots of historical module compatibility quirks, or you’ve seen your switches/routers be picky about third-party optics—worth checking your exact Cisco model/IOS expectations first. Also, any “gigabit over SX” optic lives and dies by fibre quality and patching, so if your link is already marginal, don’t expect a £38 module to fix bad fibre.

Bottom line: good value for the right, typical multimode/SX use case, but confirm compatibility with your specific Cisco platform before you make it your standard. If you want, tell me the exact switch/firewall model you’re using and I’ll say whether I’d treat this as a safe drop-in or a “test first” purchase.