If I use the inline power command in interface configuration mode, it will enable with the default PoE class, which is Class 0 or "UnknownClass". If I leave the default class can the switch automatically determine the correct class, based on the end-device, when it requests power, or should I be manually specifying the class with the parameter power-by-class?


Here is the brocade documentation. Brocade doc

The ports will follow 802.3af and at standards on brocade when the inline power command is used . These standards will monitor and adjust power as necessary based on its capability and based on the end device requirements.

Quote from reference ...

Increased electrical power - POE Plus nearly doubles the amount of electrical power available to powered devices, to 25.5 watts.

Compatible with 802.3af POE - POE Plus switches and injectors will recognise 802.3af powered devices and enable POE to them as normal.

POE Plus powered devices can also be connected to 802.3af POE switches or injectors, and are supposed to restrict how much power they use accordingly.

Smart power budgeting - 802.3at includes scope for power sources and powered devices to communicate with each other to negotiate an allowance of electrical power.

Refrence for POE power classes and versions POE multipart white paper


Using "inline power" does enable PoE for Class 0, which covers a large power range from 0.44 to 15.4 watts. This seems to intelligently hand out the correct amount of power.

  • You should accept your answer so that the question doesn't keep popping up forever, looking for an answer.
    – Ron Maupin
    Sep 3 '16 at 18:48

To expand on this:

inline power

Covers from 0 to whatever the maximum output of the port is. For instance, you're using a Brocade ICX7250-24P, it's max output per port is approximately 30 watts. Simply putting the 'inline power' will allow you to plug in anything that supports PoE (15.4 watts) or PoE+. This is typically not a good practice, and it is recommended that you figure out what class of power you need, and assign it to the interface.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.