– Rephrased from a customer email –
I’ve read the product description for the "UbiSwitch Module 3 x 10GBASE-T + 8 1GBASE-T Switch” and had a question regarding the 10GBASE-T ports. It says that these can operate at 1000BASE-T. Can they go any lower?
It entirely depends on the SFP module you use. If you use a 10G SFP module that can support 100Mbps, then yes, you can run the 10G ports on UbiSwitch at 100Mbps, no problem.
FYI, most 10G SFPs can run as low as 100Mbps, but always check the spec sheet on that.
As an example, I’ve just tested H! Fiber ASF-10G2-T | 10G/5G/2.5G/1G Copper SFP, which is a pretty generic and cheap 10G SFP. It makes no mention of being able to run at 100Mbps, but it works just fine running at 100Mbps on UbiSwitch.
The truth is that nearly all the PHYs used inside most of these 10G SFPs can run as low as 100Mbps, so most 10G SFPs have no issue running an RJ-45 connection at 100Mbps.