How The W310 Switches Detect A Powered Device; Specific Resistance Signature (Ieee 802.3Af); Pd Connected - Avaya W310 User Manual

Chapter 13 PoE (Power over Ethernet) Features

How the W310 Switches Detect a Powered Device

The W310 switches use the specific resistance powered device signature and PD (powered
device) connection verification to determine whether to supply power to a give port. Figure
13-1 shows the process.
Figure 13.1 Powered Device Detection

Specific Resistance Signature (IEEE 802.3af)

The W310 switches apply a low voltage to the power feed pairs and measures the current. A
resistance of 19k. to 26.5k. is considered valid according to the IEEE standard; if a valid
signature is detected, power is supplied to the port.

PD Connected

Once power is provided to a port, it is checked periodically to see if a PD is still connected. If
a PD is disconnected from a powered port, then power is denied to the port.
228
Start Check
Valid Resistance
Signature?
No
No
No
Yes
Sufficient power?
Yes
Apply Power
Yes
PD still
connected?
Avaya W310 User's Guide