RF interference cause loss of LAN connectivity on WAP11?

Sunday night, my Linksys WAP11 was working great! Monday morning, none of our laptops could reach it. I also could not reach the config web pages on the wired LAN. I ran the Linksys config utility, and it also could not find the WAP11. I hauled the unit to work and plugged it into the LAN there. It worked great! Hauled it home and it still would not work (either wireless or LAN). Running the site survey utility on one of the laptops, I found another new 802.11G network on the same channel. It was running with no encryption, so I tried doing an ssh login to my server through it. Worked fine! Looked at the server log for the IP of the login and found it corresponds to a DSL from the local phone company (not my DSL provider). So... figuring MAYBE this is an RF interference problem, I pulled the antennae off the back of the WAP11 and powered it up again. I was then able to reach the config web pages and change the channel. Put the antennae back on, and all is well.

So... can RF interference (especially 802.11G) tie up the processor in the WAP11 so much that it won't even respond to http requests from the LAN? That's my only explanation as to what's going on. Any other ideas?

THANKS!

Harold

Reply to
Harold Hallikainen
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Were you broadcasting your SSID? The zero conf wizard will attach to aps that are broadcasting the SSID and avoid those that are not. If you were attached to another network trying to attach to your AP which could have a different IP then it wouldnt work

m2c.

Reply to
Airhead

Which version WAP11? There are 5.

Nice troubleshooting job. Did you try moving the WAP11 to a different channel.

Since you didn't mention the USB configuration port, I'll assume you have the 2.2, 2.6 or 2.8 version.

802.11g traffic is treated by an 802.11b radio as interference if run in the 802.11g only mode. Since you were able to detect the offending access point, it is not running in 802.11g only mode.

I have no idea if wireless traffic or noise can busy out the WAP11 processor to that extent. I do know how to busy out any AP with various probes, MAC address generators, and DoS attack generators. However, I really doubt your neighbor is into such things. I would guess(tm) that you should not be affected by "normal" 802.11g traffic. To be sufficiently affected, they would need to be continuously sending traffic, such as TIVO video wireless connection, file sharing, or a major downloader. High traffic is the key.

I can sorta simulate your setup as I just "found" a WAP11 v1.1 (close enough). However, it will have to wait until later next week. Meanwhile, could you interrogate your neighbor and get the model number of their wireless access point. If uncooperative, you can extract it's MAC address, which should give me a clue as to the manufactory and possibly the model. Ask about the type of traffic as it would need to be continuous to do such damage.

Also, ask the neighbor a loaded question. "When the computers are idle, is there any substantial LAN or wireless taffic visible as continuous flashing lights on the modem or router?" If so, it's probable they have a worm or trojaned computer.

Reply to
Jeff Liebermann

Thanks for all the comments! The status page does not give the revision of the hardware. The firmware revision is v2.05, Aug. 04,

2003.

Regarding the neighbors WLAN, over the air it's identified as a Belkin something or another. It was running with no encryption, MAC filtering, etc., so I was able to connect to it and use ssh to log into my server. I then checked my server logs and found the IP address of where the login came from. Did a host lookup of the IP address and found it to be a Verizon DSL. Other than that, I don't know which neighbor is running the network.

I was finally able to connect to the WAP11 over the wired network by disconnecting the antennae from the WAP11. At least I think that's what got it working. From the configuration web pages over the wired LAN, I was then able to change the channel and get my wireless network running again.

So, it seems strange that something on the RF would mess up the LAN connection, but it just may be what happened.

Harold

Reply to
Harold Hallikainen

Well, it's usually on the serial number tag. Sometimes it's a seperate sticker (that falls off). If it has a USB port on the back, it's a 1.0 or 1.1. If no USB, it's 2.2, 2.6, or 2.8. Firmware version 2.05 corresponds to the latest from hardware mutation v2.8.

formatting link

Nice of them to leave it wide open for you to use. What I was hopeing to determine was if it was one of the new Super-G, Turbo-G, or Pre-N wireless routers.

Connect to it again, and then run: arp -a on your computer. You'll see the IP address of the Belkin router along with its MAC address. If not, ping the router once and it should appear. The MAC address might tell me the manufacturer and possibly the model number (if it's on a list).

formatting link
formatting link
you feel really ambitious, point your web browser at their access point IP address. It probably doesn't have a password. As I vaguely recall, some Belkins routers display an initial status page that does not require a login. Anyway see if you can get the model number, or

2nd best, the MAC address.

Well, it seems your analysis of the problem was correct, that 802.11g traffic was killing your WAP11. The best I can do is try my WAP11 v1.1 under similar test conditions. However, it will have to wait as I'm going to be rather busy starting Monday.

Not so strange if it's what I'm guessing is the cause. My guess(tm) is that an ordinary 802.11g access point would not cause this problem. However, there's something about either a Super-G, Turbo-G, or Pre-N access point that's causing havoc. All of these are 802.11b compatible and should theoretically NOT cause any such interference, but that's based on manufacturers tests, not those of customers. What you're seeing may not be something they've test for. Dunno.

Reply to
Jeff Liebermann

Thanks again for all the ideas. Since my WLAN is now working, I'll probably just leave it alone and not dig further. It was such a strange problem, I just had to ask!

I'd be interested in hearing if anyone else can duplicate the problem.

THANKS!

Harold

Reply to
Harold Hallikainen

Another follow - up on the issue. Last weekend I got a WAP54G and had the same problem. I THINK I've tracked it down to a temperature problem! The WAP was located on a top shelf in an upstairs room that gets rather warm. The WAP54G didn't work there, but when I hauled it to work and plugged it into the network there, it worked fine! Trying to figure out what's different between work and home, I was left with the RF environment, the LAN configuration and traffic, and temperature (it's always cold at work). So, exhausting everything else, I stuck the WAP54G in the refrigerator at home for 30 minutes, then took it back upstairs, but put it on the floor instead of the top shelf. It worked great! So, all my previous writings about RF interference MAY have been totally wrong. It appears the WAP series is a bit sensitive to temperature. On the same shelf I have a Linksys 8 port router, a SIP phone adapter, the DSL modem, and a few other things. I'm going to put the WAP54G on a lower shelf and try to cool off that room! Thanks to the group for the ideas on the problem!

Harold

Reply to
harold

Does it really run that hot?

I am planning to put a LinkSys WRT54GS wireless router into a sealed box and your post is not very encouraging. :-)

Thanks.

Reply to
meATprivacyDOTnet

Following up further... I'm STILL having loss of LAN connectivity with the WAP54G. If I just wait a while, it comes back. If I power cycle it, it generally comes back. Has anyone else had this happen? Any ideas? THANKS!

Harold

Reply to
harold

Yup.. had the same problem.. Goto the Linksys website, and download and install the firmware upgrade for that model.... Turns out that even though I bought it after the upgrade date, it was already shipped to the store with the older version of the firmware. Worked like a charm for me.

Reply to
Peter Pan

The firmware in the WAP54G seems to be the latest available on the Linksys web site. I went ahead and bootloaded it again. I THINK this may still be temperature related (as I suspected higher up in the thread). It can get to 80F where I had the WAP located. I've now moved it to another cooler room. We'll see if it's more reliable. Anyone else notice unreliable LAN connectivity to the WAT54G?

THANKS!

Harold

Reply to
harold

The firmware in the WAP54G seems to be the latest available on the Linksys web site. I went ahead and bootloaded it again. I THINK this may still be temperature related (as I suspected higher up in the thread). It can get to 80F where I had the WAP located. I've now moved it to another cooler room. We'll see if it's more reliable. Anyone else notice unreliable LAN connectivity to the WAT54G?

THANKS!

Harold

Reply to
harold

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