We know that some of small network devices can be powered by ethernet, that is, we say PoE. Now there are not only PoE and PoE+, but also UPoE.
What are their differences?
Power over Ethernet or PoE describes any of several standardized or ad-hoc systems which pass electric power along with data on twisted pair Ethernet cabling. This allows a single cable to provide both data connection and electric power to devices such as wireless access points, IP cameras, and VoIP phones. Its maximum power delivered by PSE is 15.4W.
What’s new in PoE+? That is, the maximum power delivered by PSE of PoE+ is 30W.
How about UPoE?
In 2014, Cisco created another non-standard PoE implementation called Universal Power over Ethernet (UPOE). We also call it PoE++. Its maximum power is 60W.
Cisco Universal Power Over Ethernet (UPOE) extends the IEEE Power over Ethernet Plus (PoE+) standard to double the power per port to 60 watts. It can extend resilient network power to a broad range of devices, including virtual desktop terminals, IP turrets, compact switches, building management gateways, LED lights, wireless access points, and IP phones.
In the newest Cisco Catalyst 9000 series switches family, there are Catalyst 9300 and 9400 can support UPoE while Catalyst 9200 only support PoE+.
See the datasheet:
Cisco Catalyst 9300 Switch Datasheet.pdf
Cisco Catalyst 9400 Switch Datasheet.pdf
Cisco Catalyst 9200 Switch Datasheet.pdf
Table 1. Comparison of PoE, PoE+ and UPoE.
Property PoE PoE+ UPoE Power available at PD 12.95 W 25.50 W 51W Maximum power delivered by PSE 15.40 W 30.0 W 60W Minimum cable type Category 3 Category 5 Category 5
Besides, there are other Comparison of PoE parameters.
Table 2. Comparison of PoE parameters.
Property 802.3af (802.3at Type 1) “PoE” 802.3at Type 2 “PoE+” 802.3bt Type 3 “4PPoE” 802.3bt Type 4 Power available at PD 12.95 W 25.50 W 51 W 71 W Maximum power delivered by PSE 15.40 W 30.0 W 60 W 100 W Voltage range (at PSE) 44.0–57.0 V 50.0–57.0 V 50.0–57.0 V 52.0–57.0 V Voltage range (at PD) 37.0–57.0 V 42.5–57.0 V 42.5–57.0 V 41.1–57.0 V Maximum current Imax 350 mA 600 mA 600 mA per pair 960 mA per pair Maximum cable resistance per pairset 20 Ω (Category 3) 12.5 Ω (Category 5) 12.5 Ω 12.5 Ω Power management Three power class levels (1-3) negotiated by signature Four power class level (1-4) negotiated by signature or 0.1 W steps negotiated by LLDP Six power class levels (1-6) negotiated by signature or 0.1 W steps negotiated by LLDP Eight power class levels (1-8) negotiated by signature or 0.1 W steps negotiated by LLDP Derating of maximum cable ambient operating temperature None 5 °C (9 °F) with one mode (two pairs) active 10 °C (20 °F) with more than half of bundled cables pairs at Imax 10 °C (20 °F) with temperature planning required Supported cabling Category 3 and Category 5 Category 5 Category 5 Category 5 Supported modes Mode A (endspan), Mode B (midspan) Mode A, mode B Mode A, mode B, 4-pair mode 4-pair mode
(Info: Power over Ethernet – Wikipedia)
If you have any different idea about PoE, please leave your comments.
What is PoE? What is PoE+? PoE vs. PoE+