Linux Unwired

Alex Moskalyuk writes "Remember the Best Buy commercial where a puppet asks a woman for a laptop computer, and upon hearing that it's a 'wireless' laptop, starts imagining his life free of strings and limitations? That guy doesn't know it yet, but soon the harsh reality will kick in, ironically kicking him off the wireless network periodically if he uses Microsoft Windows Wireless Zero Configuration or if he wants to run Linux on a laptop with WiFi card that doesn't support Linux. This book, however, is not just about getting your Linux laptop onto the wireless network. Granted, WiFi plays a big role in today's business and personal networks, and three chapters are dedicated to exactly that purpose, but behind that wireless adjective we have a variety of technologies." Read on for the rest of Alex's review of Linux Unwired, from O'Reilly. Linux Unwired: A Complete Guide to Wireless Configuration author Roger Weeks, Edd Dumbill, Brian Jepson pages 300 publisher OReilly rating 8 reviewer Alex Moskalyuk ISBN 0596005830 summary Complete guide to wireless configuration on Linux

Infrared, Bluetooth, 802.11 (in current a, b and g offerings, 802.11i is also being discussed), wireless access points friendly to Linux, United States commercial cellular networks and GPS systems are all covered in a single title that surprisingly fits all of this information into 284 pages. All the chapters can be subdivided into two large parts - familiarizing yourself with the technology (the primer on GPS is pretty good) and running Linux on it (with code and shell command samples and lots of URLs).

Introduction

The authors start up with introduction to wireless, intended for Linux geeks who are not quite up to speed on radio technologies. The concepts of waves, spectrum and radio wave behavior are explained, so later the reader can explain what a retracted radio wave is. Then the first chapter moves on to explain antenna behavior, wireless infrastructure modes and some common problem, like a hidden node in ad-hoc infrastructure. The chapter is well-written, and you're not expected to have an advanced radio degree or ARRL membership to understand the terms.

WiFi cards

Chapters 2, 3 and 4 deal with connecting a Linux desktop or notebook to a wireless 802.11 network. The first issue is that of chipsets used in the wireless card, and even though enough research has been done already, authors discuss different quirks relevant to Intersil Prism, Lucent WavelLan/Orinoco, Aironet/Cisco, Symbol, Atmel, Atheros and Broadcom chipsets. We need to discuss chipsets instead of discussing the actual wireless cards, since some hardware may be shipped under the same brand name with different internals. "A good case in point: the D-Link DWL-650. This radio card initially shipped with a Prism II chipset and was very popular, because it worked on a Linux box. However, D-Link changed chipsets when it released the DWL-650 Version 2, choosing the ADMtek chipset. It is very difficult to tell from the packaging which version of the DWL-650 you are purchasing".

The chapters are done in traditional walk-through mode. They are not HOWTOs or compendia of reference information, available from the manufacturer's Web sites. The authors made an effort to ensure the reader is capable of starting up a wireless connection on Linux box, knowing nothing about it while learning important technology in the process. Certain wireless drivers need to be compiled into Linux kernel, so the task is not for the meek, but with detailed explanation, plenty of URLs and nice fonts and paragraph formatting O'Reilly Publishing uses to differentiate between the text, commands entered at the shell, and URLs, the book is easy to read.

Chapter 3 (available in PDF) teaches the reader how to connect to existing wireless network once the wireless card has been recognized by the system and proven functional. By the time the book hit the stores it was already a bit out of date, since the very first hotspot operator, Cometa Networks, shut down in May 2004. Chapter 4 discusses wireless security, touching WEP settings, a $20 Linuxant utility allowing the user to implement WiFi Protected Access, as well as authentication utilities wpa_supplicant and XSupplicant.

WiFi access points

The issue of WiFi access points is not trivial either, as many vendors out there will ship the product with a Windows app being the only way to set it up. However, for the access point setups that are Web-based, a browser in Linux will do the job. The most Linux-friendly access point include Linksys, Netgear, D-Link, Cisco, SMC, EnGenius, Belkin, US Robotics, Microsoft and ActionTec. Again, harsh reality kicked in between the time the book was written and went to press, and it's sad to see yet another Linux-friendly access point vendor quitting the market.

Not satisfied with commercial offerings out there? Chapter 6 takes the reader into the task of building your own access point. Don't forget that an access point doesn't need to be a compact portable - your old 486 with Linux on it and a wireless card connected to it might serve the purpose. Unfortunately, after all the hardware is bought and assembled, the final product might still cost you the quadruple (in case you go with smaller form-factor motherboards and CompactFlash cards for software storage), so consider this more as a geek project, not a viable solution. The authors use LinuxAP distribution for this task.

16 pages are dedicated to hacking Linksys WRT54G access point with Sveasoft, described as disruptive technology by Robert X. Cringely. The authors also take a brief look at Wifi-box and OpenWRT.

Other wireless technologies

Bluetooth, Infrared, cellular and GPS chapters follow the same chapter plan - first the basics of the technology and simple use case scenarios of what you might use it for, then the hardware needed to implement the wireless technology, available Linux software to do the jobs, accompanied with the list of shell commands to successfully talk to a wireless product, and after that typical applications of the working link.

The authors tested various wireless data plans in the United States, although this data, once again, is constantly changing as the operators buy one another and introduce new data plans. The winner of the quality and the fastest download tests, by the way, was a Motorola v120e phone on Verizon Wireless network. In upload speed tests a Merlin C201 PCMCIA card on Sprint PCS network won. T-Mobile also offers a PCMCIA card for its GPRS network, so the authors install and run it under Linux in Chapter 9.

The last chapter discusses using Linux computers with GPS devices and open-source GPSdrive project for reading GPS data.

The book

For those just venturing into the wireless world, the book would be useful. All the information provided on WiFi connectivity can perhaps be googled and found in various HOWTOs. With wireless operators, GPS systems and Infrared connection one would have to rely on enthusiast sites and newsgroups. Having such informative title that covers all of the technologies would be very useful to a Linux enthusiast.

With that, the book can be quite overwhelming, although it's probably not intended to be read from page 1 to the end. There's usually more than one correct way to do things in Linux, and for each successful project another competitor appears on SourceForge the next day. I like the authors' approach of dedicating most of the chapter space to one, leading, Linux package that seems to be dominant in the field, and then briefly mentioning the others. A notable omission is Intel's Centrino drivers for Linux, as the company is bound to become a leader in the chipset marketplace with 42% of notebooks shipped in 2003 running Centrino chipsets.

But overall the book proved to have a high informational and educational value, not only you follow the steps on setting up wireless technologies on Linux, but you also learn the internals of the technology and why certain things are done that way, but not another.

You can purchase Linux Unwired from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, carefully read the book review guidelines, then visit the submission page.

Comments

Easy solution

[foidulus]

Get an airport(or as I have, an AirMac) card!

/ducks!

Is it just me...

[Fooby]

or does wireless seem a bit overhyped? I don't own a single wireless device and I don't really see the need yet. Sure there have been times when it would be convenient to have a cell-phone, but most of the time when I'm not home I don't want people harassing me with phone calls anyway. As for 802.11*, the data rate and reliability of ethernet beats it every time for home networking use. Something about carrying around a laptop so I can browse the web at random hotspots just doesn't float my boat. I have wired access at home and at work, and if I need access when I'm at neither I'd go to an internet cafe.

Don't get me wrong, I'm not a luddite and I think these are great technologies, but for myself they just seem expensive and not terribly useful. What I do find interesting is use of WiFi for rural broadband. But that's still pretty novel.

Re:Is it just me...

[tcopeland]

> wireless seem a bit overhyped?

I thought the same thing for a while... but after working on my laptop at home with no wires for the kids to yank on/trip over, I'll never go back. If I run across something interesting, I can carry my laptop in to another room to show my wife. If the living room gets too loud, I can move into the dining room. It's very handy.

And for some reason I still get a kick out of printing something over a wireless LAN connection. Just something odd about clicking the "print" button, with no wires attached, and then hearing my printer downstairs leap into action :-) I don't know why that still amazes me, but it does :-)

Re:Is it just me...

[silas_moeckel]

It's a bit over hyped for big desktop replacement laptops (I own 3 of them) where they need to be pluged into power anyway. But for a PDA bluetooth or 802.11(abg) is rather usefull as they can get out get your mail sync etc, same goes for small light weight laptops that have decent battery life. As far as cell phones it's all about how you use it, I have a cell phone that nobody calls me on unless it's important as in router down (I'm a network guy) as in I take one or two phone calls a business day on it. It's about lifestyle as well, I take an hour plus ride on the train each way a cellphone with bluetooth, laptop and pda allows me to get on the internet to read my personal email web surfing etc without looking like a moron with piles of wires hanging around. At work wifi is nice for laptops that you might be taking around working on the network, and the usual PDA functions. I wouldent call it expensive tech either 802.11b devices run about 20 bucks less than a stack of DVD-R's or a decent sized USB key.

Re:Is it just me...

[Marble68]

On the same vein. My wife kept asking me to stand up WiFi @ home. I ended up getting the Microsoft 700 series (which they're not going to make anymore) and I must say I don't know what took me so long.

I love being outside by the pool and taking care of a backlog of emails or simply using my Mod points.

But speaking of printing; we have an upstairs game room thats my wife's office. My office is directly below hers. Anyway, the cats LOVE to lay on her desk and look out the window at the trees.
I get a HUGE kick when I print something and you'd think someone had thrown teargas into the upstairs room and several cats come barrelling down the stairs with their hair firmly perpendicular to their skin.

Great fun.

:)

Computer Book publisher's business plan

[cerebralsugar]

1.) Get a 'high-falootin' title (PHD, MSCE, etc).
2.) Paraphrase information freely available on the net.
3.) Blow college professors and get them to use it as a text book for their class!
5.) PROFIT!!

screw it, use driverloader

[np_bernstein]

So I had a belkin card which was supposed to be based on an orionco chipset; it wasn't and it didn't work. I got a netgear, because that's what they had at comp-usa and I didn't want to waste all my freetime driving around looking for a prism2 chipset where I could be sure it was a prism2.... I got the thing, tried it, didn't work, got a copy of driverloader : done.

I'm three days into the evaulation period and I'm giving them my $20 for the software. It's too easy this way to go the free/annoying route. 'Sides, at the amount of money I end up earning/hour, spending two hours of my life to get a wireless card working it costing me more that $20.

That example seemed deliberate

[SeaFox]

Why do I feel like that Best Buy Puppet example in the begining of this story was tacked on simply to stick in a Microsoft Bash.

Since the book was about Linux, there was no real practical reason for including it. Is the book going to tell how to get around the XP problem?

No.

That's a lot of type to say simply "some wireless cards aren't supported by Linux out of the box".

Absolutely

[NineNine]

Absolutely. Wi-Fi is no where as near as reliable as good ol' ethernet, and won't be for a while. Certain cordless phoens even disrupt wi-fi. It's cute for home use, but I would *never* rely on wireless for a business use. It's just not reliable enough. I *need* my network up 100%, or my rent doesn't get paid. Wi-fi is cute, but it doesn't cut it for me. On top of that, ethernet is cheap, and very, very easy to run. At my business, we have suspended ceilings with hundreds of feet of Cat 5, and a few $20 switches.

Ah, the bitter irony

[lorcha]

Not sure why your cards working in XP is ironic, but whatever. Anyhow, what distro/kernel are you using? I ask, because under Knoppix, my D-Link and Orinoco cards "just work", as you say. I didn't have to compile anything, tinker with anything, or ... well.. frankly even do anything except insert the card into the PCMCIA slot.

Since you are into security, perhaps you would be happy getting an STD? Security Tools Distribution, that is. That livecd will likely have any tools on it you need as well as detect your cards without any fuss.

Best of luck.