Appendix C: Wireless Device Network Indicators

Network Indicators

The following table describes the network indicators of wireless devices.

Information type	Description
RSSI (received signal strength indicator)	Displays the power level of the wireless signal: 0 to -75 dBm indicates a good power level. -75 to -85 dBm indicates an average power level. ≤ -85 dBm indicates a poor power level with risk of outage.
LQI (link quality indicator)	Displays the measurement of the strength and/or the quality of the received frames.
PER (packet error rate)	Displays the ratio of the number of packets which do not reach a destination over the total expected number of packets. It is expressed as a percentage. The calculation of the PER (packet error rate) indicator depends on the type of indicator: Device indicator: provided by the device. Panel Server indicator: calculated over a sliding window equal to 20 x publication period, and refreshed every 30 seconds. Link indicator: displays the higher of the two previous indicators.

Information type

Description

RSSI (received signal strength indicator)

Displays the power level of the wireless signal:

0 to -75 dBm indicates a good power level.
-75 to -85 dBm indicates an average power level.
≤ -85 dBm indicates a poor power level with risk of outage.

LQI (link quality indicator)

Displays the measurement of the strength and/or the quality of the received frames.

PER (packet error rate)

Displays the ratio of the number of packets which do not reach a destination over the total expected number of packets. It is expressed as a percentage.

The calculation of the PER (packet error rate) indicator depends on the type of indicator:

Device indicator: provided by the device.
Panel Server indicator: calculated over a sliding window equal to 20 x publication period, and refreshed every 30 seconds.
Link indicator: displays the higher of the two previous indicators.

Signal Quality Level

PER Link indicator:
The PER link indicator is based on the PER of the Panel Server and the PER of the device as explained in the following table:

		PER of the device
		PER < 20% or no device PER	20% ≤ PER < 30%	30% ≤ PER
PER of Panel Server	PER < 10%	Low	Medium	High
	10% ≤ PER < 15%	Medium	Medium	High
	15% ≤ PER	High	High	High

Signal quality level:
The signal quality level is based on the PER link indicator and RSSI as explained in the following table:

		RSSI
		RSSI > -75 dBm	-85 dBm < RSSI ≤ -75 dBm	RSSI ≤ -85 dBm
PER link indicator	Low	Excellent	Excellent	Good
	Medium	Good	Good	Fair
	High	Fair	Weak	Weak