thinQmaster Virtual testing partner Adaptive practice exams that find your weak spots and drill them. Every answer explained. From $69
Enroll

thinQmaster

Find your exam

Five questions free, before you decide.

Step 1 · choose a vendor

In one of our camps? Your practice exams come with the tuition — they are on your study page already.

Commonly confused · Networking Fundamentals

PoE vs PoE+ vs PoE++: What's the Difference?

These IEEE standards deliver DC power over Ethernet cabling, and each newer one supplies more watts. Standard PoE suits basic phones, PoE+ handles most access points and PTZ cameras, and PoE++ powers high-draw devices like multi-radio APs, displays, and lighting.

PoE (802.3af)

vs

PoE+ (802.3at)

vs

PoE++ (802.3bt)

PoEPoE+PoE++
IEEE standard802.3af802.3at802.3bt (Type 3 and Type 4)
Power at switch port (PSE)15.4 W30 W60 W (Type 3) or 90 W (Type 4)
Power at device (PD)12.95 W25.5 W51 W (Type 3) or 71.3 W (Type 4)
Pairs used2 pairs2 pairs4 pairs
Typical devicesVoIP phones, simple sensorsWi-Fi APs, PTZ cameras, video phonesHigh-end APs, digital signage, thin clients, LED lighting
Backward compatibleBaselinePowers af devicesPowers af and at devices
Remember it

Each plus roughly doubles the watts: 15, 30, then 60 to 90.

Exam tip

Expect questions matching wattage to a standard, or asking why an AP boots with reduced radios (it needs more power than the port supplies). Know the power budget of the whole switch can also be the limit.

Tested on

More Networking Fundamentals look-alikes