Wi-fi is lossy for some but not others

[pentium]

Because of compatibility issues (no wireless B) and my laptops were the only ones on the network that were getting booted off while everyone else was peachy I rebuilt my wireless configuration.

802.11b with WEP128 and 802.11g with WPA are now handled separately by Linksys WAP11 and WAP54G access points respectively. 802.11n with WPA is being handled by a TrendNET access point. Each access point is configured so they are two channels apart from eachother which limits possible interference.
All three access points are high up on a shelf in the living room and are unobstructed.

My laptops (both using wireless G) are now working flawlessly.
My roommates however are now having problems with the G and N access points booting them off.
I experimented by streaming multiple videos on my laptop and at different locations in the house and I could not drop the connection or find dead zones. One roommate is closer to the access points, the other is further. My room in in between.

I'm stumped because I can't blame both the laptop hardware or the networking hardware on obvious grounds.

[lmcancu]

Re: Wi-fi is lossy for some but not others

First, what channels have you configured the access points? Are the channels at 2.4GHz or 5GHz? In both case, channels are overlapping. There is about 60 Mhz available in 2.4 GHz, or three non-overlapping 20 MHz channels. 802.11n lets you operate in 40 MHz mode, so it is impossible to configure all three APs two channels apart without them being overlapping. The best you can do is adjacent to each other (1,6,11) with the 802.11n using 20 Mhz.
http://en.wikipedia.org/wiki/IEEE_802.11

What do you mean by booted off? Do your roommates see the access points (i.e. what is the signal strength they see?)

[digge]

Re: Wi-fi is lossy for some but not others

It might be something interfering with the signals. Just about everything use 2.4GHz these days and have a chance to interfere which might make a connection drop. Should get back up in quite short time though when nothing is interfering.

The difference in how good radios are at filtering out crap is huge between brands and even models. Some of the "cheaper" brands are worse with interference then others.

What might be interfering is hard to say, can be spikes on the electrical to the routers, but if that was the case you would have problems to. Could be a microwave, Bluetooth stuff, wireless phone or something else.

Also ive seen some laptop manufacturers shipping with drivers old as *beep*. Might want to look into that cause interference sturdiness is one thing that drivers might address to some extent.

Without a spectrum analyzer it can be tricky to troubleshoot interference but try isolating and turn of any electrical appliance in the vicinity and see how it goes.

[pentium]

Re: Wi-fi is lossy for some but not others

the B access point is at channel 2, the G access point is at channel 4, and the N access point is at channel 6. the radio in my WRT54G is programmed for channel 14 however it's currently turned off.
It is worth noting that the apartment modem, router, switch and access points are all having to work through an APC UPS so the internet in the side of the wireless stays alive when the power goes out.
I have a wi-spy module somewhere which could spectrum analysis but I'm suspicious of the included software because no matter where I go the readout feels like it's the exact same.
the WAP11 however was recapped about three weeks ago (STONE caps were causing it to not boot). I have not yet gotten around to doing the other two access points if that helps at all.

The other roomates are getting "booted" from the net in that they will be working and it will just drop the connection and they have to reconnect.

[digge]

Re: Wi-fi is lossy for some but not others

Your channels are overlapping, not that it should make a difference connection wise, but performance wise it will. Have a look at this image and you see what i mean.

http://upload.wikimedia.org/wikipedi...LAN%29.svg.png

As for the wispy i think there is other software then the bundled one that is better. It can be hard to track down what goes wrong. Any radio in rfmon/promisc mode should have a noise level and a SNR level and so on reported. However some devices report odd values while in that mode so might not work. If im not misstaken kismet have an addon for wispy if that helps any.

[severach]

Re: Wi-fi is lossy for some but not others

If the N access point is in 40Mhz "rape-my-neighbor" mode then no other router in the vicinity will function at all. 40Mhz takes up almost the entire spectrum and neighbor unfriendly mode stomps on all other routers. Look for the "neighbor friendly" setting and keep the Mhz down if you want to run more than one. Forget N routers because don't provide the performance they claim. Based on G and B testing they should be moving 65% of 300Mbit or 200Mbit. Current 300M models barely break 30% of 300Mbit or 100Mbit which is why so many are outfitted with 100Mbit switches. Many are not much faster than G routers. For now N is just advertizing baloney to get you to buy more of what you already have. Save your money until manufactures provide the speeds they claim.

Most wireless routers need more than recapping to become reliable. They are built on the low edge of reliability and need their electronics to be improved. When that's done they need to be stress tested for a week with 10+ WPA clients to see which firmwares hold up under load. Booting WPA clients when there are too many is a very common problem having mostly to do with substandard firmware. Many work fine with no encryption, WEP, and 1-4 WPA clients which wasn't unreasonable years ago. Now with a Kindle, iPad, iPod, iPhone, Wii, xBox 360, PS3, TiVo, TV, printer, Skype phone, desktop, and laptop for every person in the household, a wireless router that craps out at 4+ WPA clients doesn't look so good. Some can do... six (6) WPA clients without booting any off. Whoo-hoo!

I started on this project early 2011 but haven't have time to complete it.

A modified Linksys WRT160 by Broadcom is the best I've found so far. There are two revisions of the WRT160. No external markings were changed. The revision is only discernible by parts placement on the board. The early one is so bad that Linksys had to improve it. The second one might last the warranty period. Both need improvement to be any good.

[lmcancu]

Re: Wi-fi is lossy for some but not others

try setting the channels to 1,6, and 11, and put the 802.11n in legacy mode (20 MHz mode) and see if that helps

[shadow]

Re: Wi-fi is lossy for some but not others

You are using Linksys hardware. I currently use a WRT54gs router, I remember a couple of years ago reading that some wireless chipsets do not like connecting to the router.

To attempt to remedy this, 3rd party firmwares updated the wireless drivers on the router. Not all routers could use these updated drivers so it was common to produce two firmwares. Once using the old driver and one using the new driver (usually dubbed ND)

Perhaps this issue affects the WAP54g series as well? It is worth looking into I guess. From memory, some Intel chipset wireless cards were giving grief to these routers.

[pentium]

Re: Wi-fi is lossy for some but not others

The N access point is already in 20mhz mode.

I left my laptop logging and I was actually wrong about me having a flawless connection. My laptop disconnected from the wireless several times a day but reconnected so quickly that nothing ever noticed.
I also did as you said and switched over to the three channels you recommended.

[lmcancu]

Re: Wi-fi is lossy for some but not others

Did the performance improve or are the connections still disconnecting?

[shovenose]

Re: Wi-fi is lossy for some but not others

Wait... so why again do you have 3 routers? I don't understand.
I would just use a single G or N router. While Linksys is a marginally better brand than TrendNET you may as well use the TrendNET is probably better because it's newer...
If you're using only that one, people get randomly kicked off? is that what you're saying?
An option to consider would be the "Guest AP" mode that some Netgear N routers have: You can create a 2nd wireless network with WEP (for example) in addition to the main wireless network (WPA for example) and then you've got two networks with only one router.

If all 3 of the APs are all right next to each other right now that could be a problem.

[ratdude747]

Re: Wi-fi is lossy for some but not others

agreed on interfernce. even microwaves can skewer the signal. try moving your routers.

[weirdlookinguy]

Re: Wi-fi is lossy for some but not others

Extend my apologies to your roommates. They probably just want to come home, kick off their shoes, relax and use the internet for a bit. Something they used to be able to do until their brilliant roommate set up THREE routers in a situation where one would be plenty.

Set up the newer N router for G/N operation, chuck the other two in the bin, find some cheap WiFi cards for your shitty old laptops, and call it a day.

[shovenose]

Re: Wi-fi is lossy for some but not others

Extend my apologies to your roommates. They probably just want to come home, kick off their shoes, relax and use the internet for a bit. Something they used to be able to do until their brilliant roommate set up THREE routers in a situation where one would be plenty.

Set up the newer N router for G/N operation, chuck the other two in the bin, find some cheap WiFi cards for your shitty old laptops, and call it a day.

While all of your politeness may not have been required, this was pretty much what I thought too

[ratdude747]

Re: Wi-fi is lossy for some but not others

Extend my apologies to your roommates. They probably just want to come home, kick off their shoes, relax and use the internet for a bit. Something they used to be able to do until their brilliant roommate set up THREE routers in a situation where one would be plenty.

Set up the newer N router for G/N operation, chuck the other two in the bin, find some cheap WiFi cards for your shitty old laptops, and call it a day.

minus the cursing, agreed.

[kaboom]

Re: Wi-fi is lossy for some but not others

If the N access point is in 40Mhz "rape-my-neighbor" mode then

solder up a waveguide out of some copper flashing and have a little fun.


Don't hardboil your eyes.

[pentium]

Re: Wi-fi is lossy for some but not others

G seems to of calmed down (looks like it was more the fault of some bad Intel laptop wireless cards), B still needs to be rebooted from time to time to work (nobody uses it except me from time to time and when idling it will just decide to hang) and N is still hopeless. I have recapped it again, redid the heatsinks I added and reloacted it to a more well ventilated area and it's still up and down several times a day. It's so bad everyone decided to stop using it.

[japlytic]

Re: Wi-fi is lossy for some but not others

Not all Wireless-N equipment is made the same.
Wireless-N equipment supporting 300Mbit or faster use MIMO technology, which requires multiple antennas, which would result in better coverage.

Saying again from elsewhere, wireless and powerline networking should only be used to supplement your wiring dedicated to networking, not replace it.

[kc8adu]

Re: Wi-fi is lossy for some but not others

great fun.built several nasty rf "toys" with those.
(looks at a box of 2m172's)
the donor item often has everything you need.

solder up a waveguide out of some copper flashing and have a little fun.


Don't hardboil your eyes.

[Brian10962001]

Re: Wi-fi is lossy for some but not others

Severach speaks the truth! To this day I haven't found a Wireless N router that did anything special over a trusty old wireless G router. I think the big price drop reflects this. Also every time I would connect one of the wireless N routers B was hopeless, and suddenly some of the neighbors SSID's quit showing up (despite new ones popping up). Pick up InSSIDer, it's an awesome free program, and run it. It will show you who's broadcasting where. It's also showed me when one of my neighbors routers was going out and sending out piles of crap from time to time. It's a must have software when trying to daignose wireless issues. Also if it's possible, turn off the wireless N and see what happens.

*assuming you're still having issues seeing as this was months ago ")*