Voltage of 802.3af/at is fine with RB4011 (takes 18-57V). However it doesn’t talk 802.3af/at protocol and thus Linksys should not power it up … unless it’s possible to forcibly enable PoE out on Linksys …
@Elans, previous poster (@Urjamal) is asking about PoE and suitable injector.
Mikrotik is offering RBGPOE with declared max current of 2A. Which with short ethernet cables should be just enough. If one uses ethernet cable longer than just simple patch cable, then one needs to make sure that used ethernet cable is high-quality low loss. With too large voltage drop current would increase, possibly beyond RBGPOE’s declared max current. In that case it would be better to use 48V power adapter (rated at 1A or more), such as 48POW.
@mkx you are right, I misread @Urajmal question. As mentioned, we do offer RBGPOE. In case you are willing to power this device through injector, we do recommend to use at least 48V PSU. Up to ~1A is recommended on Ethernet cable and the longer will be the cable, the higher will be a voltage drop.
It says it needs 23W constant and it could take up to 44W.
The RB4011iGS+5HacQ2HnD-IN without attachments consumes max 23 W.
So if you don’t supply power to PoE equipment on ether10, 23 W is max usage, not constant.
(Another example of attachment is USB equipment but the device has no USB port)