Suppose I have a device that supports 10/100/1000/10GBase-T ("Firewall") and another device that supports 10/100/1000/NBase-T ("Modem").
Now, I could connect these two devices using 1000Base-T. However, I would prefer the higher speed of NBase-T. So there needs to be a device in between that "translates" NBase-T to 10GBase-T. The classic idea here would be a switch that supports both NBase-T and 10GBase-T. But due to other constraints, such a switch would be quite expensive (i.e. me needing 8+ ports with at least one more 10GBase-T port).
Because of this I consulted a networking-experienced friend and he suggested using a PoE-injector that supports NBase-T and 10GBase-T.
My question is now:
Do PoE-injectors typically require the negotiated input and output speed to match or can they do the kind of "translation" layed out above?