Looking for a troubleshooting guide for wireless clients, comparing RSSI and SNR values when connected to LAP(s).
Currently using Cisco WCS 6.0 for troubleshooting wireless clients.
WCS displays that a wireless client has a RSSI -80 and SNR 20.
What I'm looking for is a graph/table that will compare the RSSI and SNR values and display what connection will be achieved (strong/weak/low).
What is the recommended RSSI and SNR vaules for DATA and VOICE wireless clients.
VOICE - RSSI -67 (no higher) SNR 25 (no lower)
DATA - RSSI - 73ish (no higher) SNT 20ish (no lower)
Of course you have some wiggly room with DATA...
Thanks George for your feedback. Customer are using Cisco 1141 Access Points.
Is there a specification guide showing all RSSI values max and min values.
in the datasheet for the AP 1140 you've a receive sensitivity list were you'd see which rate you'll have at which signal strenght.
Regarding RSSI to dBm comparison I also wasn't able to find one - I think every vendor keep it a secret.
No worries. Remember to rate helpful post as it helps others navigate to quicker answers. Cheers and happy holidays !
I found this from a trawl of the web that I did a while back...does this help?
The wireless standard 802.11b operates in the 2.4-2.485GHz (gigahertz) radio frequency (RF) band; RF is measured in decibels (dB). Wireless cards often come with client software that displays signal strength in dB or dBm (a variant of dB that provides an exact correlation to the power of the radio signal in watts).
Note: The minimum power sensitivity on most 802.11b clients is -96dBm (very low). If your software displays "Signal/Noise" or "SNR" in dBm, you can convert this to dB by subtracting the minimum power sensitivity, -96dBm, from the number displayed as "SNR" or "Signal/Noise". For example, if the Signal/Noise is -47dBm, you would convert this to dB as follows:
-47dBm - (-96dBm) = 49dB
If your wireless card software is indicating that the signal-to-noise ratio (SNR) is greater than 10dB, you are getting the maximum available bandwidth, or 11Mbps (megabits per second). An SNR higher than 10dB won't increase the amount of bandwidth beyond this maximum (in the example above, with an SNR of 49dB, the bandwidth is still 11Mbps, the maximum available rate). When the SNR drops below 10dB, however, the maximum data rate drops:
Maximum data rate
Even though the maximum data rate goes down, the connection will still be maintained as long as you have an SNR of 4dB or greater.
Other factors can affect the quality of your wireless connection. The list below is incomplete, but it may offer some explanation for poor performance that occurs even when the signal strength is good:
Throughput is a measure of the speed of your wireless connection. Defined as the amount of data transmitted in a given time period, throughput is based on many factors. Three important factors are described below: