Wireless diagnostic hardware

[Sunny Davis]

For 802.11 wireless network. Large warehouse, about 20 mobile Rf users. 25 access points.

Can anyone recommend any hardware/software/utility that would help us figure out where our problem is?

Thanks,
Sunny

[M/Q]

Not to sound snide, but could you please tell what kind of a problem you are having? That would help out quite a bit.

[Sunny Davis]

Well- I was really just looking for some diagnostic materials so that we could narrow down what our problem is. Sorry, I was going to include the problem info in the first post but I have posted the problem in forums and have worked on it before without any luck so I was just hoping to find out what the experts out there used to help them sniff out wireless interferences etc.

The problem is our mobile guns are kicked out randomly throughout the warehouse.

We have done sniffers, traces, site surveys etc and nothing has turned up anything.

Thanks-

[M/Q]

By guns, I assume you mean something like mobile readers. I was curious as to what the physical dimensions were and what materials the building was made from. Also how did you locate the 25 WAP's and how is the channel interference issue handled? What equipment are you using at this time to do RF surveys and interference scans? What are the WAP's brand and model and do you have some sort of enterprise wireless gateway controlling them?

[Sunny Davis]

thanks for your interest and reply, mp. Here are the specs for our facility and answers to your questions.

We are using about 15 mobile handheld guns; Symbol model 6846. The access points are HP WL520 (they are really made by Orinocco). Our warehouse is about 660,000 sq feet and ranges from 30-35 ft high. To place the the AP's we did a site survey with the guns and some wireless laptop cards testing signal strength. Channel interference- we placed all the AP's on a map and drew a coverage area circle according to the antenna's expected range. Then made sure none of the AP's with overlapping circles had the same channel.

We currently have nothing to do interference scans. There is a ping utility on the symbol gun that we have used to test AP response time. That is it. The guns are working, so we did not want to invest in something if we didn't have to. So that is all we have used up until now.

Thanks again-

Sunny

[M/Q]

You missed the important thing I was looking for. What are the walls/ceilings made of and are there and other large flat and or metal surfaces in the warehouse?

You may want to look at investing in a software package or device that might help in this area. If it is not a full time need there are locations that will rent such devices as well. I am familiar with a device called a YellowJacket or the program called AirMagnet. If you search the forums about either you will find some recent threads about them.

[Sunny Davis]

Yes we have much metal racking, shelves and machinery throughout the warehouse.

The walls and ceiling are made of insulation and metal sheeting.

I have heard of Air magnet and YellowJacket both. So those are recommended?

Thanks-
Sunny

[M/Q]

I think you might be having some issues with multipath interference. It will give you headaches big time. I would suggest either device, but in this case I might think the YellowJacket is a little better as it has better signal capture programs IMHO. I am sure others will have different opinions, that is why I suggested searching the forums.

[Sunny Davis]

Great thanks MP!

[spiderbite]

What kind of antennas are in use, how high are they in the ceiling and did this infrastructure ever work?

When did it stop?

Was the warehouse full or empty during the survey? Do varying levels of stock affect the reliability of the wireless?

[Sunny Davis]

Thanks for the reply spider.

We are using WIP antennas from Hyperlink, 12dbi, omni-directional.

This setup has improved over the previous setup by alot. But this is the same problem as we had before- it just happens much less frequently with the increased coverage. (We have added more AP's and bought these stronger antennas to increase the coverage. )

We have had these same issues since we began our wireless venture about 3 -4 years ago. Just varying in frequency.

The level of stock has varied during the site surveys. Our racks reach all the way to the ceiling and seem to have just a little effect on the reliability. We have racked areas and open areas and the open areas have the same trouble, maybe a tad less frequently- it is hard to tell.

The antennas are mounted about a foot from the ceiling and hang down 4ft.

Thanks,
Sunny

[Sunny Davis]

If anyone knows a good reseller for the yellowjacket or airmagnet handheld devices, I would be interested in talking with them.

Sunny

[keenanj]

Hi AirMagnet is the best tool for the job.

You might want to look at the new AirMagent surveyor it is the only product on the market that does a active site survey it will graphicly show your dead spots, sig/noise, connection speed etc in you whold building.

[Sunny Davis]

Well- management nixed the yellowjacket and airmagnet for now. Wants me to research other ways to narrow down problem. (Ways that don't cost $)

Can any one recommend any freeware tools that might be of use for tracking signal and channel strength, interference etc.. Any aspects of spectrum or demodulation analysis?

Or any good reference materials that might lead me to my problem?

THANKS very much for any suggestions/advice.

Sunny:D

[keenanj]

Thats too bad.

We see all too often management putting off the required purchase for security / performance products untill it is too late and company data is stolen, business grinds to a halt or worse.

You can use the freeware tools out there netstumbler, ethereal, kismet etc but without the expert analysis AirMagnet brings in it is hard to solve actual problems.

If you can find a proxim rangelan2 fhss card you will be able to use the 2.4Ghz spectrum analyzer to pinpoint noise related issues i use one in conjunction with other tools.

if you can post the specifics of you problem I may be able to help as i am working with another client that uses the symbol guns in a warehouse at the moment.

[Sunny Davis]

Jeff,

Thanks for your reply. You mentioned that with the proxim card I could use the spectrum analyzer- where can I get that from?

The specs of our warehouse are listed in the above posts. The main problem is that the guns get randomly locked up and booted out of the application ( terminal emulation) back to the login screen. We use symbol 6846 handhelds. We have also tested on symbol wrismounts and had the same problem.

I will check out the other freeware tools you mentioned (ethereal, kismet), as I don't know about any of them so please list any helpful ones you know of.

THANKS-
Sunny

[M/Q]

Hope you don't mind I just thought I would inject this link as it lists all the normal utilities. If you are not running Linux, you may limited to more expensive shareware prog's. But the basic NetStumbler prog is effective for the existing channels. Other RF interference or multipath that we discussed before will not show up on any of these utilities.

http://www.wardriving.com/code.php

[keenanj]

You can find the rangelan2 cards on ebay if you are lucky they have long since been discontinued we have a few but they are for in house use.

You can run Ethereal on windows for wired networks only.
To use Ethereal on 802.11 networks you must install in on linux along with a monitor mode patch and a orinoco or prism card.
You must also be a sniffer expert to decode the raw traces and make any sense of them.

airsnort is another linux tool that will detect and try to crack weak wep keys.

It takes an advanced linux user many days to set this stuff up the first time and get it all working take it from me. And then it still takes a lot for time to trouble shoot issues. In the end it is more cost efficient to buy AirMagnet.

[Sunny Davis]

Thanks very much. I understand and will relay to management.
Also we don't have Linux.


Hopefully I can find something.

:) THANKS!

Sunny