Aerohive BR200-WP, Hardware Reference Manual

Page: 112 / 124

Chapter A
110 Aerohive
Power over Ethernet Port Pin Assignments
The pin assignments in the PoE (Power over Ethernet) Ethernet ports follow the TIA/EIA-568-B standard (see
Figure 2 and Figure 3 on page 111 ). The ports accept standard types of Ethernet cable—cat3, cat5, cat5e,
or cat6—and can receive power from power-sourcing equipment (PSE) that is 802.3af-compatible. If you
use cat5, cat5e, or cat6 cables, Aerohive PoE devices can also support 802.3at-compliant PSE. Such
equipment can be embedded in a switch or router, or it can come from purpose-built devices that inject
power into the Ethernet line en route to the device. Because PoE ports have autosensing capabilities, the
wiring termination in the Ethernet cable can be either straight-through or crossover.
Figure 2 Pin assignments for an Ethernet PoE port
PoE ports are auto-sensing and can automatically adjust to transmit and receive data over straight-through
or crossover Ethernet connections. Likewise, they can automatically adjust to 802.3af Alternative A and B
power delivery methods. Furthermore, when the Alternative A method is used, the ports automatically allow
for polarity reversals depending on their role as either MDI or MDI-X. In 802.3at, the 1/2 and 3/6 wire pairs
connect to DC source 1 and 4/5 and 7/8 pairs to DC source 2 in PSE. Although the exact polarity depends
on the PSE design, the Ethernet ports can support all possible options.
Table 1 Wiring Usage for an Ethernet PoE port
802.3af Alternative A (data and
power on the same wires)
802.3af Alternative B (data and
power on separate wires) 802.3af wiring options
Pin Data Signal MDI
*
* MDI = Medium-dependent interface for straight-through connections
MDI-X MDI or MDI-X 1 2 3 4
1 Tr DC+ DC- - - - DC1+ DC1- DC1+ DC1-
2 Transmit - DC+ DC- - - - DC1+ DC1- DC1+ DC1-
3 R DC- DC+ - - - DC1- DC1+ DC1- DC1+
4 (unused) - - - - - - DC+ DC2+ DC2+ DC2- DC2-
5 (unused) - - - - - - DC+ DC2+ DC2+ DC2- DC2-
6 Receive - DC- DC+ - - - DC1- DC1+ DC1- DC1+
7 (unused) - - - - - - DC- DC2- DC2- DC2+ DC2+
8 (unused) - - - - - - DC- DC2- DC2- DC2+ DC2+
ETH0
(View of the ETH0 PoE
Port on the AP340)
8 1
Pin numbers