Signal strength / link test WRT54GS

Hi,

How do I perform a link test (display radio signal strength, noise etc) for a link with WRT54GS boxes in each end...?

Do I need to install 3rd party software?

Thanks for any hint on this issue

regards

Tor

Reply to
bushtor
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As others have suggested, you can use Netstumbler, Boingo, or other client utilities.

However, I like the alternative vendors firmware. My favorite for this week is DD-WRT. Telnet to the router, login, and run the "wl" command. See:

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some of the options. Lots of info in there.

I also use SNMP to extract signal quality and connection information from the WRT54G. I'm working on a set of instructions on how to use SNMP with the WRT54G (which are taking forever). Meanwhile, see: |

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a short explanation of how to use a MIB browser with SNMP and the WRT54G.

Reply to
Jeff Liebermann

Although not as good as Netstumbler, the Boingo client software gives more information than most wifi client programs. It's available for free at

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in the Downloads section. It can be used not only to connect to Boingo sites, but also to connect to any access point like one you may have at home.

Bruce

Reply to
bjs555

Install software Net Stumbler

Rohit

Reply to
Roy Amin

Jeff,

Thanks for these infos Jeff.

The reason for my post is that I have one WRT54GS as access point and 6 of the same box in client mode (Alchemy fw in all). Main point is sharing an internet connection. Link distance is not too long but the clients experience very intermittent internet access. It can be good for a minute and then no throughput for five minutes.

Are there any special issues with the WRT54 as access point and the same box in client mode? Since there are onlky 6 clients I thought this should work well....?

Thanks for comments or issues or settings to check...

best regards

Tor

Reply to
bushtor

I see no details on the client side or nor indications as to the environment. How far is "not too long" and are there any obstructions in the way? Are you in a tall building that overlooks the world through glass walls? Are you in an industrial environement? Do you have other 2.4GHz devices in the neighborhood such as cordless phones or wireless video devices? Do you see the problem? Without an adequate description of the hardware and RF environment, it's difficult to even guess what's wrong.

However that's never stopped me from guessing. Sounds like some type of interference. 5 minutes could be a leaky microwave oven or a cordless phone. Both are able to successfully interfere with communications.

My favorite test is to just ping the access point from the client. I'll assume Windoze XP Home on the client which comes with a rather insipid ping program. I suggest downloading fping from:

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offers the sequence numbers the MS removed. This makes lost packets obvious. Run: fping 192.168.1.1 -c -t 5000 which will ping the access point once every 5 seconds (to not be too obnoxious). What you're looking for are radical increases in latency which indicates retransmissions caused by corrupted packets. In extreme cases, the TCP will time out and the packet will show as lost. If you run it on all 6 client mode radios at the same time, it will show the extent of the problem. Do NOT be suprised if you find that one or two have a severe packet loss problem while others work just fine. That means the intereference is affecting the client, not the main access point.

As for monitoring the signal strength and S/N ratio, this is best done at the client end. For the WRT54G in client mode, that's: wl noise wl rssi (receive signal strength) wl tssi (transmit signal strength) wl rssidump wl channel_qa (requires setting channel_qa_start). I don't know which of these will yield the best numbers, but methinks it should be easy enough to try. If you want SNMP OID's, I'll have to dig them out later when I'm in the office.

Yes. Some of the wl comands don't work.

The number of clients have nothing to do with interference problems.

Reply to
Jeff Liebermann

IFAICT he's using one WRT54GS box as the AP and six WRT54GS boxes as clients.

I'd have to imagine that they should work well together, though running Alchemy FW he's unlikely to get any support from Linksys. I would have guessed some kind of interference as well, though it's always possible that the Alchemy folks missed something...

Reply to
William P. N. Smith

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