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Your Own Linux Wireless Access Point
prostoalex writes "Peter Seebach decided to build his own Linux-based 802.11b wireless access point. The article on IBM DeveloperWorks talks about the hardware and software requirements, implementing the operating system on the CompactFlash card, loading Apache and Perl onto the server. The build-it-yourself wireless point is not going to be cheaper than commercially available products, but its educational value is immense." And HaeMaker writes "We have all seen the 802.11b/g booster made from a Pringles can. Well, these guys have taken the idea, put some math behind it to find the optimal can size and have turned it in to a cool product."
It's not the kill, it's the thrill of the chase.
Toshiba Magnia SG20
Certainly, rolling your own is a learning experience but this is hard to beat. Where to you get a switch to put in a roll-your-own box?
Life is the leading cause of death in America.
Did anyone else notice they mentioned the wi-fi sniffers?
:(
little keychain devices that tell you when your in a hotspot.. thats great!
http://store.yahoo.com/directron/etector.html
found a place that has them too since the link on the webpage is already broken
Actually, if you read the article, it devotes a part explaining this...
I'm not the devil.. just his advocate.
!Sig
Its better because now he can spend his time in his mother's basement tweaking his l33t linux access point instead of going outside to meet girls.
Wait...
obviously, if you read the article, you would have found that he did it just to see what it would take. He also believes that Linux offers a lot more in firewalling, NAT, etc, than a typical Linksys home networking AP does (and I agree).
Why this is news for nerds, stuff that matters, I will never know...
I found the article basically pointless and nothing more than what anyone who would be likely to try a project like this already knows..
I wish I had read this article before going out and purchasing my Linksys BEFW (sorry, can't remember the rest of the model number) wireless access point. It seems to drop connections at random, requiring a reboot of the router by pulling out and reinserting the power cord. The logs it gives are nowhere near as comprehensive as the ones that snort would send me every morning, and while I can configure port forwarding and IPSEC passthrough, etc., I miss the fine-grained control I had over all the options when I had a Linux router.
A mini-ITX case and some assorted hardware and I could have made a much more configurable, sturdy access point for only a little more money. Sigh.
Karma: Excellent Birds (mostly as a result of listening to Laurie Anderson)
Building your own access point with hostap on any given linux box is pretty trivial, and cheap too if you consider you've probably already got the box laying around. All you need is a Prism2 chipset card, and there's a ton of them around.
My company is doing a similar thing, only using mini-PCI cards to keep the box's footprint as small as possible.
It works like a charm, and you can even build security on top of it. hostap supports WEP out of the box (although that's not really security) and MAC address authentication, even via radius!
I've worked extensively with this sort of thing, very useful and if you already have a linux box, much cheaper than an off the shelf access point.
I'm working on something similar, with the soekris net4521 board, (same as the one this guy used) but with a demarctech 200mw high output wireless card, for much greater range.
I'm doign most of the work with an old P200 right now.. got that out of a dumpster at a local school. My box does the AP, routing, dhcp, dns, and eventualy i'm goign to try and set it up as a wirewall. the ability to SSH into the AP is very handy.. none of the AP's out there (besides super expensive Cisco IOS based AP's) do that.
how long before the Heath Company sues about using the name Cantenna , which goes back at least to the 1960s?
The comments have so far been dumb. Let me point out that the real strength in this tutorial is the idea that you can construct a sort of mini-appliance with ease using Linux. Before you downplay this man's efforts, consider that what he is doing is demonstrating one of the key strong points of Linux that will keep Linux around for a long time: Its use in appliances and specialized embedded devices. In fact, this is such a critical area that Microsoft has become more lenient and more "open" (I use the term loosely) with their competing WinCE product.
It's not hard to take some of the author's ideas and twist them around for other custom networking applications, or even make cheap wireless appliances based on the concepts he's presented. Hats off to the man for providing us with a bit of education.
In much the same way reading the article is better than trolling.
1) you can get more out of the box. (near-endless possibilities for customization) - similarly, the article probably contains more than your average slashbot response (like this one, for instance:))
2) it's fun and rewarding to do things for yourself. much like actually reading the article and drawing your own conclusions is fulfilling, while buying off-the-shelf solutions leaves you feeling empty and purposeless - the same way you should feel after posting trollish first posts.
This is throwing an 802.11 card in a computer and configuring it. Start etching some circuit boards, break out the soldering iron and spectrum analyzer, then you can considering it building...
Tired of being "punished" by the Slashdot $rtbl since 2002. I'm now over at http://soylentnews.org/ .
Linux as a platform for network appliance sounds like a marraige made in hell. It's a great desktop operating system, but it doesnt scale well into small places, has a lot of bloat, and tends to consume resources.
Of course, security should always be of great concern, and this is why WinCE has made such headway with internet devices as of late - it was created delibirately to be small, robust, secure and stable - everything youd want from your network.
Of course, it must be noted, that linux was written in C which makes it very good, since C is object oriented.
I don't need no instructions to know how to rock!!!!
A similar project can be found here
:
This post on their forums caught my eye
I have been sucessful in using the ROM image in a CompUSA branded 4 port switch/router for US$39.95. www.compusa.com has computer strores throught the USA. The router, from what I understand, is made by FMI. It uses a Samsung 4510B CPU, ADMtek ADM6996 5 port ethernet switch device, 512kB flash and 4MB SDRAM. The part appears to be able to take up to a 4MB flash. I'm using a 2MB part in a TSOP socket. uClinux boots up to prompt and the ethernet port works.
Using technical knowledge, some neato hardware and Open Source resources I made a Wireless Access Point using Linux.
It was really, really hard but well worth it and the Earth was saved.
The End.
The surprise isn't how often we make bad choices; the surprise is how seldom they defeat us.
Why is a Super Cantenna more powerful than a home-made Pringles can? linkage
What I want to know is why bother making your own Pringles can.....?
If you build a WAP with Linux, Build 5, alter the
code and build a network of wireless access points.
Each access point should have 2 cards, possibly 802.11a for the uplink and 802.11b as the downlink.
This can be accomplished. Say for instance you
build a star shaped network and "home" is in the
center and the host you need to reach is 5 miles
to the east, your routing table would have rules
on each WAP that will relay your IP traffic the the proper destination.
I've thought about this before, and it could be interesting for metropolitan areas:
a mini-distro for AP's that:
- shields the internal (personal) net, from a public, wireless net.
- routes between the private net, the public net, and the internet.
- do proper routing between AP's: it would be nice if there was a way to use your neighbours excess bandwidth to the internet, or use them as a failover when there's an outage just for you.
- provide proper limits: stop providing to the public if you reach 80% of your monthly bandwith limit, prioritize a bit of the bandwith for your personal net (so that other people can't use up all the available bandwith so there's none left for you), maybe only provide your connection to "members" of the network, etc.
- make it available in an easy updatable flash image for homemade and commercial AP's.
- make it configurable for people who have even more interfaces: multihoming with adsl and cable for instance, IR/visible light links/...
The idea would be that while not everyone has the expertise to configure their routers for all these features, everyone who wants to can just reflash their AP with an image, and be able to provide/get wireless services, and be a part of a real emergent wireless network. It'd be interesting for other reasons too: where I live for instance, all upload speed for residential cable/adsl connections is capped at 128kbit. If I want to send files fast to a friend a couple of blocks away, they could be just routed over the wireless network, via a couple of hops: no need to go over the internet - chances are the speed will be a lot better than 128kbit that way. Also by cooperating in a network like this, you'd have increased speed and reliability for all - not everyone uses up their bandwith / monthly volume limit all the time.
Correct me if I'm wrong, but using CompactFlash as a storage device on an embedded appliance/application whatever is a bad idea because of the half-life of CF.
I wanted to do something similar a while back, and I wanted small. I figured using a VIA EPIA-M and a CF with CF to IDE I could create a pretty small server. Perfect for Kiosks, but I ended up finding a page all about CF to IDE and why it shouldnt be used as a boot device (yeah like I bookmarked it) and was discouraged.
Anyone have any experience with that?
Im dreaming ofa big bndwdth, That can resist the
Update your FLASH. My BEFW has been very stable.
I use a laptop, zaurus, and my kids computer upstairs is also conneted to the net by WiFi
If it took you this far to realize it was a joke, you are: a genius
It's a great desktop operating system
If it took you this far to realize it was a joke, you are: pretty enlightened
but it doesnt scale well into small places
If it took you this far to realize it was a joke, you are: about average
Of course, security should always be of great concern, and this is why WinCE
If it took you this far to realize it was a joke, you are: fading fast
that linux was written in C which makes it very good, since C is object oriented
If it took you this far to realize it was a joke, you are: breathing my air. Please stop
psxndc
The emacs religion: to be saved, control excess.
Didn't you read the summary?
Prevent email address forgery. Publish SPF records for y
Actually most build your own stuff is like this. The prototype or early phase is wicked cheap (Pringles can, for example) so you start jacking around with it ... then you just keep on adding stuff that you need until BAM! $300 access point built from scratch.
... hey, free second machine.
Pretty much the way most of my computers were built. 'Oh neat, I can buy that computer for $300 - a complete working system."
Hmmm - needs a sound card. (cha-ching!)
Hmmm - needs a better video card. (cha-ching!)
Hmmm - needs more memory. (cha-ching!)
Hmmm - needs a bigger hard drive. (cha-ching!)
Hmmm - needs a quieter CPU / case fan. (cha-ching!)
Hmmm - needs faster CPU. (cha-ching!)
Hmmm - needs a CD burner. (cha-ching!)
At the end, only the case, power supply and mobo are original on your uber "$300" machine. And then only maybe.
God help the guy that keeps all the spare parts, then goes out and buys a case, power supply and mobo to install them all into because
Glonoinha the MebiByte Slayer
I certainly have too many old boxes laying around. Yes, building your own access point is much more interesting. And you get to customize so that you have the features that you want. But in the long run it will be a lot more expensive to operate that PC that uses a few hundred of watts of power than an access point powered from a small wall wart that uses a few watts of power. If, like most users, you leave your internet connection up 24/7, you will find that any savings that might exist in building a device from spare parts are grossly offset by the cost of running it.
This is not an agrument for or against building your own, just a warning to those who might read the original post and think they can save money by building their own.
I'm an American. I love this country and the freedoms that we used to have.
Im dreaming ofa big bndwdth, That can resist the
I've tested it myself-
h owto.ht ml
My homemade one made out of a large Pedigree dogfood can works better than the Cantenna.
~50ft more range with a much broader spread.
The building instructions I used are here:
http://www.turnpoint.net/wireless/cantenna
I browse at +5 Flamebait- moderation for all or moderation for none.
Pebble Linux
The FIC MAAT Server from FIC can serve as a Linux wireless access point.
Specs:
Embedded Linux
Transmeta Crusoe TM5600 500MHz
On-board 128MB SDRAM (512MB max)
2X 2.5' IDE HDD 20GB (120GB max)
4 ports 10/100 Mbps Ethernet Hub Switch
Built-in Wireless Access Point (802.11b)
Dimensions: W246 X D240 X H56mm
Unfortunately, it is rather pricey at $995 MSRP or $645 direct from the FIC California branch. Interesting nonetheless.
the heathkit cantenna wasn't really an antenna ... it was a dummy load for testing transmitters. The signal was safely disapated into the oil, not the air. Same name, but different purposes.
Besides, it was never registered as a trademark by Heathkit (ah, the simpler days!), or any other company.
HIV Crosses Species Barrier... into Muppets
Actually a pringles can is a very bad wifi antenna. To work effectovely it should be a couple of meters long. The can shown has a larger diameter, which should be much better.
You can calculate the optimal size yourself here.
Markus
I love soekris gear. Soren is working on a less full featured unit just for people who want to build a vanilla wAP.
However, if you have a soekris, and you want to DIY a wAP - you should really insert a brain to look at the potential advantages instead of just pulling a linux + hostAP mode whoopdedo.
#1. Flexibility. Since this is standard x86 gear, you get to easily make this an 802.11b AP; but now w/ FreeBSD's ath driver (appropriated for l00n1x by madwifi) you can upgrade it to an a/b/g AP. Leet, suddenly the price is a little more justifiable (considering that Enterasys & Cisco gear that was proportedly going to be upgradeable in such a way is conveniently not now that the newer standards are out).
#2. Try doing something security related; Soekris also offering 3des crypto accellerators that are supported by OpenBSD & more. WEP blows, WPA is a proprietary nightmare; IPSec on the other hand... well that is interesting, and doable - especially with for instance, OpenBSD (FreeSwan for linux, but that's not quite up to the same standards).
#3. Maybe you want to make an access point for a commercial purpose, but don't want to spend an arm and a leg getting a proprietary product to do so, or you find that most of the free offerings kind of blow. Safe yourself grief and frustration with something like wicap (http://www.geekspeed.net/wicap/) Then you still get to potentially draw from the security benefits mentioned in #2 by using OpenBSD; plus you have something that is quick & easy to setup and get working.
Don't just do this to put a prism card into hostAP mode, that is incredibly dull. A waste of time & money. Not to mention, about as useful to write about as another wardriving article.
I've been busting my arse to put together a suitable Linux Wireless Access Point HOWTO for months.
m l
Finally it's in the process of getting published at the Linux Documentation Project.
Slashdot links to some chucklehead's one pager.
http://oob.freeshell.org/nzwireless/LWAP-HOWTO.ht