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Some senior staff have old fashion thinking that interference is around us and no solution to solve it. And they think interference is the only problem to affect the wifi connection... I understand we cannot eliminate interference but we can do something to reduce/compensate it, right? And interference is ONE of the reason to affect wifi connectivity/stability, there are other reason like multi-path, hidden-node, mismatched power, near/far, ... My question is: I have AirMagnet Laptop Analyzer on hand and already capture the traffic in different location. How can I interpret them and make conclusion. Is there any good reference guide/ book to effectively use AirMagnet tools? I really want to improve the situation and thank you in advance!

JY

I suppose you should start with AirWise feature of this software. It would direct you to high-level problems that exist in your wireless network. Then you can dig deeper into the real reasons for unsatisfactory performance of your wireless network.

In my opinion, an Airmagnet manual will only show you how to use Airmagnet software. The only way to interpret packets is by experience. How does anyone get experience? You have to look at how each packet interacts with each other. For example, a beacon transmits every 10ms or the packet interaction of association. This means you have to study. CWAP may be close but you may need to read the IEEE 802.11 specification. There is also Laura Chappell's book which gives you tips on how to analyze but it's in Wireshark.

Start at layer 1 and use a spectrum analyzer. Make sure all cables have been tested also. Check duplex and speed mismatches on AP ports and all ports on all links back to the controller if used.

Next I'd break out the Frame/Packet analyzer and see what's going on. Like CWNP says "The Packets never Lie" Are you getting transmit errors? Try some throughput testing from wireless to the AP then from wireless to a wired working computer. Compare the result. Would not hurt to test the connection from the AP port to other parts of the network, can't assume the wired network is perfect.

[quote]we can do something to reduce/compensate it, right? [/quote]

Depends on the source of interference and your layout but yes, you can do a lot about it if your budget allows.

You should be able to contact AM to get a copy of the guide. Like Bucky said, it will help you learn the software but might not help you find the problem. Also I forgot to ask. Is the problem intermittent or happens all the time? This question always gives me a good starting point when I have to analyze a wifi prob.

Yes! the problem is intermittent! thank you.

Dual radio AP? If so, intermittent connecting to 5GHz and 2.4GHz??

May I refine my question: Is there any source (website/reference book) to demonstrate the usage of AirMagnet to prove PHY problem like RF interference, multi-path, hidden-node, mismatched power, near/far, or other mentioned in Sybex CWNA book? Thanks!

JY

James,

I would speak with your AM sales engineer they typically will have access to seminar or technical briefings where they will cover this, in some cases they may have actual scenarios that they have created for demonstration. As always YouTube is always a good place to go as well.