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I understand that Gigabit POE is not possible with midspan adapters from my CWNA reading however I have seen midspan adapters claiming this capability. Does the new POE+ aka 802.11at change that stance?

Blaze Escribi?3:

I understand that Gigabit POE is not possible with midspan adapters from my CWNA reading however I have seen midspan adapters claiming this capability. Does the new POE+ aka 802.11at change that stance?

I am not sure about 802.11at in regards to Gigabit and midspan because I have not read it yet.

Proprietary solutions that allowed for midspan power injectors with Gigabit have been around for a long time, they just were not technically compliant with the original 802.3af PoE standard.

Yep, the new amendment does provide for midspan PoE with Gigabit Ethernet. The references below are from Draft 4, but I'm fairly certain this hasn't changed in the ratified document.

From 802.3at, 33.2.1 PSE location:

PSEs can be compatible with 10BASE-T, 100BASE-TX and/or 1000BASE-T.

From 802.3at, 33.2.2 Midspan PSE types:

1000BASE-T Midspan PSE: A Midspan PSE that results in a link that can support 10BASE-T, 100BASE-TX, and 1000BASE-T operation (see Figure 33???¡é?¡é?????¡é?€??7).

If you're wondering, Figure 33-7 shows a midspan injector providing power via 2 of the 4 used copper data pairs. Alt A uses wires 1,2,3,6 and Alt B uses wires 4,5,7,8.

Thanks for the response guys. So in terms of the CWNP exams will they be changed anytime soon to reflect the change or should I think of the "old way" for now?

Expect the exams to be up-to-date and accurate in accordance with the new 802.3at spec--this holds true even if the practice test says otherwise (update forthcoming). If there is a question relating to the use of gigabit PoE and midspan injectors, the answer will reflect the explanation provided on this forum.

Wonderful thanks for the clarification, glad to see CWNP updates exam material regularly. That was always an issue with another vendor neutral cert, you had to answer questions based on technologies from 5+ years before....