GLC-SX-MM vs GLC-SX-MMD? What’s the difference?

Some of our customers seem puzzled and are asking what the difference is between GLC-SX-MM vs GLC-SX-MMD? Which one is right for my equipment?

Our short answer is – none! However, we will try to explain this in more detail. It’s related to changes in Cisco’s product nomenclature of their OEM transceivers, and it happened a long time ago – in 2012, Cisco announced End-of-Sale and End-of-Life Announcement for the Select Cisco Gigabit Ethernet SFP Modules. (This was discussed in another article – Is GLC-SX-MM EOL?).

Before that moment, Cisco’s Part number for 1000Base-SX transceiver was GLC-SX-MM, but after that change, they replaced this product with GLC-SX-MMD. We guess that at this moment, Cisco introduced DDM (Digital Diagnostics Monitoring) or DOM (Digital Optical Monitoring) as a standard feature in their GE SFP portfolio from that moment forward.

You could argue that GLC-SX-MM vs GLC-SX-MMD is the difference – DDM/DOM support! But we would say that all our compatible modules have DDM/DOM functionality as a standard feature from the beginning of our presence in the compatible transceiver market! In this particular case, both compatible versions for replacing GLC-SX-MM or GLC-SX-MMD will be based on the same our product – 1.25G-SFP-550D, which has DDM/DOM on board – and as a side effect, you will enjoy a great savings, so maybe it is worth considering – Should You Buy 3rd Party SFP?

Have a suggestion, questions, or comments – please, Contact Us!