Wireless Access

How do I tell if my network is running optimally?  My real-life performance of clients is not real impressive.  For example, a client connecting at n 40MHz standing very near the AP will only get data transfer rates of maybe 50Mb/s and a b/g client will get a max of 20 Mb/s.  The controller says my speed is much higher, We are using iperf to test and the same test scenario over the wired network gets close to 1 Gb/s.

I have Spectrum Monitor running but I haven't been able to find much information on how to read the graphs.  How do I know what good or poor values are for Noise Floor, Channel Busy, Client Health, retried frames, etc.  It seems like I have a lot of retried frames but I have nothing to compare it to.

Thanks

Hi Dobrien,

Do the clients experience low throughput when associated on g-radio or a-radio ? Or is this is a new deployment ? Either way, here are some diagnostic commands that can give you an idea of the RF environment:

1. show ap active - Check the channel distribution across the APs. Ideally you should not see adjacent APs on the same channels or channel pairs. This can introduce co channel interference. You might want start off by adding lower DFS channels to the AP Regulatory Domain.

2. show ap arm history ap-name <AP Name> - Check if there are considerable number of channel changes due to Interference. One of the reasons could be co-channel interference. Depending on the distance between two APs, you might want to lower the Tx Power of the APs

3.  show ap debug radio-stats ap-name <AP Name> radio 0 advanced | include usy,oor - Gives you channel utilization and Noise Floor values on a-radio (5GHz) - Absolute NF value > 90 is desirable, and channel busy in the order of single digits

4.  show ap debug radio-stats ap-name <AP Name> radio 1 advanced | include usy,oor - Gives you channel utilization and Noise Floor values on b/g-radio (2.4GHz) - Absolute NF value > 90 is desirable, and channel busy <= 20ish

5. show ap debug client-table ap-name <AP Name> - Gives you the wireless link speed at which the client associated and an idea of the retries

6. Disable 80MHz assignment if you have closely spaced (~ <40ft) APs operating at high Tx Power.

Hope this helps.

Thanks smantha, I will try these commands.

It is a new deployment and I believe users in both bands are having problems.