BioSehnsucht
Member
Interesting, never heard of this. I've always seen warnings not to mix for danger of toasting things.PoE and GigE are incompatible, though I believe you can get mixed purpose switches (some PoE some GigE). Reason being GigE uses all 8 conductors on the wire, 10/100 only uses half of them so you can use the rest for PoE.
Not true. The GigE spec allows for power by doing some monitoring of power differential for each bit rather than on/off operation. Whether or not a cheap switch supports it, I have no idea. But my Juniper EX-4200 certainly does.
I have some PoE capable devices that have gig ports on them. I'll try plugging them into a cheap PoE gig switch the next time I'm over at my buddy's ISP. He bought a bunch of cheap ones for an IP phone system. These devices DO work on my Juniper switch, and they also link up at 1000/full.
Some googling and I come to realize perhaps what I've always heard about and seen actually deployed were not "proper" PoE power injectors but instead just dumb voltage injectors.
It does appear there is some fancy detection using resistance to determine the presence of a PoE device and how much power it needs. And it appears to be compatible with GigE..
I honestly hadn't seen any that were GigE and PoE on same port but I haven't looked for them, as I haven't needed anything PoE.