Definition of terms

Term	Definition
Detection Signature	Resistance of PD during detection.
Classification Signature	Used by PSE to identify the PD device type and vice versa.
MPS	Maintain Power Signature
Dual Signature (DS) PD	Has independent detection signatures, classification signatures, and MPS on each pair set.
Single Signature (SS) PD	Shares the same detection signature, classification signature, and MPS between both pair sets.
PLC	Physical Layer Classification
DLC	Data Link Layer Classification

PoE types, classes, standards, power needs for SS PDs
Classes	Associated PoE types	Associated IEEE standard	Maximum power at PD port Minimum power at PSE port
Class 0	1	802.3at	13 W / 15.4 W
Class 1	1 or 3	802.3at or 802.3bt	3.84 W / 4 W
Class 2	1 or 3	802.3at or 802.3bt	6.49 W / 7 W
Class 3	1 or 3	802.3at or 802.3bt	13 W / 15.4 W
Class 4	2 or 3	802.3at or 802.3bt	25.5 W / 30 W
Class 5	3	802.3bt	40 W / 45 W
Class 6	3	802.3bt	51 W / 60 W
Class 7	4	802.3bt	62 W / 75 W
Class 8	4	802.3bt	71.3 W / 90 W

PoE types, classes, standards, power needs for DS PDs
Classes	Associated PoE types	Associated IEEE standard	Maximum power at each PD pairset
Class 1	3 or 4	802.3bt	3.84 W
Class 2	3 or 4	802.3bt	6.49 W
Class 3	3 or 4	802.3bt	13 W
Class 4	3 or 4	802.3bt	25.5 W
Class 5	4	802.3bt	35.5 W