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Cutting Through a Wi-Fi Traffic Jam?
eric3xxx asks: "A week or so after Christmas, I tried to connect to my home wireless network and while I could see my access point I could not connect. After scanning the network, it turned out that there were at least twenty new access points in my apartment building (and in the surrounding buildings). Most of them had names such as 'linksys' and were all set on their respective vendors default channel (apparently a lot of people received 802.11b/g WAPs as presents). I tried changing the channel on my access point, starting at 1 and continuing through all of the channels, and none of them worked (probably since the channels overlap). In any case, I have no clear solution to this problem. I suppose I could boost the signal, however, that also increases noise. Perhaps I could convince my neighbors to put together a shared wireless network. I may just switch to 802.11a since it isn't as widely used." Has anyone else had success in configuring their APs to work in an areas of heavy wireless traffic?
If your router supports it, grab an open source firmware, and step outside the normal 1-11 channels. Channels 12 - 14 are almost guaranteed to be empty.
802.11a
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
as it is the phones. A friend of mine recently got one of those new fancy 2.6ghz cordless phones, and was calling me and complaining that his wireless kept going out. I just said "phone...". He then put 2 and 2 together and realized that every time his phone rang, he lost his signal.
Gotta love the FCC's bandplan. Stacking wifi and cordless phones onto the same spectrum.
I work for the Department of Redundancy Department.
the default password on linksys wireless routers is "admin" im sure it will work still :)
The 802.11b/g spectrum is being loved to death in your building. If you've got twenty devices trying to share only three non overlapping channels (1,6,11) its a mess if anyone wants to go fast.
Setting the channel is the first step but you'll still get adjacent channel interference. Setting SSID *DOES* *NOT* *HELP*, nor does WEP/WPA. SSIDs define a group of nodes that are going to associate but the media layer (OSI layer 2) is *shared* for 802.11. That means two properly secured networks on different channels are still sharing the same stream of NAV (network allocation vectors) and they'll be stepping all over each other.
I could go on about this but I've got the flu and you've got internet access - get Matthew S. Gast's fine O'Reilly book on 802.11 and learn all the gory details for youself.
I am very easy to get along with, but I don't have time to waste being nice to people who are being stupid. -Theo
The "Turbo 108Mbps" products are only adding to the problem. The reason it is only available on chan. 6 is that it spreads itself across TWICE the bandwidth of "normal" 802.11g products (normal being IEEE/WiFi compliant hardware). There are limited channels defined for 802.11@2.4GHz, using these socalled "enhanced" products just further pollutes the spectrum and further exacerbates the problem of airspace congestion. Your neighbors (and ultimately yourself also) will suffer more than anyone benefits.
I liken it to laying down across a couple of seats on a crowded bus, or getting a huge SUV and parking it diagonal across two spaces at the supermarket - it's just rude.
RF doesn't penetrate into metal; it travels along the outer surface of it. A Faraday cage completely encloses a volume and since there is no way for RF waves of the outer surface to travel to the inner surface (short of travelling through the metal, which they can't), the inner volume is shielded from the RF.
A Faraday cage can have holes in it, but the bigger the holes, the more RF is let through. There is a relationship between the size of the holes and the wavelengths that seep through so if you know which wavelengths you want to keep out, you can tailor your cage to match your requirements.
A simple Faraday cage experiment is to wrap your mobile phone in tin foil and try calling it.
sigs are hazardous to your health
Install a computer that connects to many open access points, and get more than 10Mbps overall. Hopefully you can find enough (up to six non-overrlapping) to get 18Mbps or more.
You could use NAT32 if you insist on using windows to make this work.
Question: Does anyone know what happens with port forwarding in situations like this? Can one effectively play an online game through a series of linked cable modems?
Locate your AP at the outside corner of your flat. Attach a pair of reflectors to the antennas, such that radiation will be concentrated only on your flat.
e x.html
By directing the power over 90 deg instead of 360, what do you think you have just done? Not only have you increased the transmit power, you've also vastly increased the receive gain.
Reflector templates can be found here:
http://www.freeantennas.com/projects/template/ind
I was in a situation where I needed broadband in an apartment w/out a connection, and used a DWL AP2000+ in client mode with one of these antennas (styrafoam, a kitchen knife, aluminum foil, and cellotape) to pull a symmetric 3.5mbps from an AP 600 meters down the street.
Make sure to put the reflectors on both antennas and point them both in the same direction. In almost all cases with such APs, only one antenna is transmit, while both receive.
Wow, that was unnecessarily offsensive post, you are right, it needs a better home page.
r minal,VNC,Emule,Ident,MSN)
Here is what is included:
Wireless:
. Power Transmit Ajusting (12.75dBm ~19mW -> max 19.25dBm ~ 84mW)
. TX & RW Antenna Selection ( Left Diversity Right)
. Support for 14 Channels (WorldWide)
+ Will support for Bridge and Repeter, WDS mode in final release
System & Network:
. Support for subnet 255.255.0.0 & 255.0.0.0
. Static DHCP
. DNS Local
. SNMPD ( Works right with mrtg)
. Support VPN Passthrough (IPSec - PPTP - L2TP )
. Add 'Server Profiles' for easy configure up to 14 Host Servers
( FTP,HTTP,HTTPS,DNS,SMTP,POP3,Telnet,IPSec,PPTP,Te
. Up to 14 Port Range Forward settings
. VPN Server (PPTP) Buld-in
. Support for Zone-Edit, Custom Dyndns DDNS
. Telnet Shell
. Remote Wake On Lan support
. Easy Reboot and Restart all service just a click
. Ping & Traceroute hacked for allow run shell command
. AutoRun Bash Script - Easy set an autorun script each time router reboot
. Status with more infos like Uptime & CPU Load, Wireless Client List
+ SSH Shell
+ Bandwidth Management
+ VPN Server IPSec
+ VPN Client (PPTP & IPSec)
** . = Current release | + = Will be add in next release **
Updates:
iptables 1.2.9
PoPToP v1.1.3
pppd 2.4.2
busybox 1.0 pre7
pptp 1.4
net-snmp 5.1
Kernel 2.4.20 Tweaked
I use these at home:
h p
http://www.netgear.com/products/details/XE102.p
Much better range and throughput than Wi-fi (in my experience) and no interference issues.
For those following along at home, you can use Google Calculator to help you with this.
1/10th wavelength is a generally accepted mesh size for blocking RF. You can be more paranoid if you want (for example the holes in your microwave oven door are about 1/50th wavelength).
To calculate 1/10th of a wavelength at 2.45GHz, type "c/2.45GHz/10" into Google. Bam, 1.22 centimeters. Anything conductive with holes no larger than that will function as a faraday cage for RF up to that frequency (and will probably significantly attenuate RF in higher frequencies as well).
The answer is no.
When you establish a connection, one IP address is used for the source of that connection, and after that, thats the path the traffic runs.
If you had two cable modems doing 5Mbps, you could download 2 things at 5Mbps (one using each modem) but you could not directly download 1 thing at 10Mbps (if its http or ftp, you could cheat and use the "resume" feature to have one cable modem download the first half while the second downloaded the second have, and then your specially written client would assemble these together.)
Channel bonding can be done with the appropriate hardware and ISP, but I'm willing to bet that your cable provider is both unwilling and incapable of setting this up. (With bonding, only one IP address is used, and the hardware passes traffic down whichever wire is free/not broken.)
If I have been able to see further than others, it is because I bought a pair of binoculars.
BTW - Microwaving water is *not* a good idea. Pockets of the liquid can become superheated, and leap into and scald your face without any prior warning.
Don't call me a cowboy, and don't tell me to slow down!
or M-x unmorse-region in emacs
I bought a DI-624 to use at home since I already connect my laptop to a DI-624 at work using a Belkin 802.11b card. Originally, I was using a Belkin router but I tested the DI-624 and found it far superior to the Belkin product in terms of range and speed.
To make a long story short, the DI-624 I bought for home was a different hardware revision than at work, with completely different firmware. Out of the box the DI-624 will not support 802.11b as it is configured to 802.11g turbo mode, so the Belkin card would not connect. I changed the wireless settings to disable the Turbo G mode and it still would not connect.
Finally, in frustration I brought the DI-624 from work (with two antennas as opposed to the newer version I had with one) along with a 802.11g D-Link PC card. Of all the combinations, Belkin 802.11b PC card, the "b" and "c" revisions of the DI-624, and a D-Link 802.11g PC card the Belkin wireless card and the "b" revision D-Link router had the best range and speed followed closely by the D-Link 802.11g card.
In the end, I simply swapped the "b" and "c" D-Link routers around and used the "b" version at home and the "c" version at work with the D-Link 802.11g card. It seems the 802.11 "b" and "g" standards leave a lot of room for interpretation, given that myself and others I have spoken to have had many problems getting products from one company to connect to another.
First of all, Have you considered that the issue could already be the walls themselves? You have not described your apartment, but many apartments have foil backed insulation or even chickenwire backed adobe or plaster in the walls.
Second, you're probably getting as much overlap from portable phones as you are from AP's in the building.
My advice differs from so many others. I say, centrally locate your AP in the apartment at the same plane as you'll generally be holding your laptop. That usually means about 30 inches for tabletop, about 20" if its actually on your lap keeping your genetals warm (and isn't that really why we all want Pentium 4 HT processors?).
If you're still not connecting on any channel, you probably have a config issue. Start with the basics. Reset the unit to factory config and change only the password. let it broadcast its SSID. Connect, then starting tightening it down. Don't sweat the hackers until you have something of value. Clearly, they don't need your bandwidth.
Also, learn about what blocks this frequency. In a nutshell, water. Anything with water. PEOPLE, for example, are excellent at blocking wifi. Your walls may have plaster that was water based. Chip off a piece and put it in the microwave for a few seconds. If it heats up, it will block wifi. The same goes for PVC plastics. Most won't, some will. A chip in the microwave for a few seconds will tell you.
I can't tell you how many times I see people in a coffee shop with wifi connection problems, when they've set the 900 ounce mochofrappafuckamacallit right next to their wifi card. DOH! If the signal is iffy, that's more than enough to kill it off.
Finally -- make sure you hit the basics. Get the latest (actually, sometimes teh second to latest) drives for teh wifi card and the AP, as well as any firmware upgrades. Don't laugh, sometimes it's really not plugged in.
You're in an apartment. Run some damn wires. Snake them under the carpet or hang the from the ceiling. Put lights on them and make them festive. Let your geek flag fly.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
Why bother with a T-1? Most folks don't upload and DSL/Cable download speeds are _higher_ than 1.4Mbps (at least in Canada). The extra cost for reliability and upstream bandwith are irrelevant for most home use.
who's talking about abuse? this is painless disposal of *trespassing vermin* the sanitary condition of the food supply of a *human being*. I can assure you that normal humans do this all the time, and that the proper place for a house pet is in the house, not running wild, as the anti-cruelty society will tell you.
I live in a town with pretty terrible (hard) water, i.e. it sure isn't pure. However, I can repeat an experiment on demand, which I have performed multiple times for various interested friends: microwave a coffee-cup full of water to just before it starts bubbling; remove it from the microwave; insert metal teaspoon into water (while wearing oven gloves); and BLAMMO, hot water everywhere. So, what's happening here? Methinks the mythbusters missed something.
http://it.slashdot.org/article.pl?sid=04/12/21/01
You quite sure about that?
Jason
Working that out with c=pi*r*2, r= (1.22/2) / pi, which gives a radius of 1.9mm / diameter of 3.8mm
So that's the maximum size of your holes.
And as the previous poster mentioned, they're doing a bit of overkill with your microwave door, with holes approximately 1/3rd of that size (1mm).
It's a time honored American tradition to shoot your neighbor's wayward animals, although in this case if you just wing the cat a couple of times it will probably get the message.
Play Command HQ online
Put simply, if there's interference, it is allowed to not work (in a safe fashion), and that's about all it can do. You're allowed to use passive countermeasures to protect yourself from interference (shielding etc), but you're not allowed to do things like signal jamming, except as a consequence of normal operation (so a WiFi AP can up its power output to the licenced limit, and see if that works, but it can't broadcast a jamming signal designed to stop the other APs working). It also can't (e.g.) make the antenna dangerously hot, make the case live, or do anything else that makes the equipment dangerous as against failed.
I appear to have a blog. Odd.