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This is a good point, and probably worth clarifying by linking to one of the many projects that's dual licensed under the GPL and a BSD license. An example is the wpa_supplicant project.

no ad-hoc connections were allowed for safety reasons

More likely they just don't want anybody reselling the service. Pop a second Wi-Fi card into your laptop, get a merchant account to verify CC numbers and you're ready to make a killing undercutting their price by 50%. At least you'd recoup your own WiFi cost, with only 2 sales. Come to think of it, it wouldn't require ad-hoc anyways.

A simple example would be deciding on your e-mail system. Sounds easy, right? And it is. If you know - in advance - what sort of e-mail system it is you actually want. Just saying "e-mail" doesn't tell you very much. If you need a great deal of power in the mail processing engine, you're probably going to want Sendmail. If you need to blast through vast quantities of e-mail very quickly, Postfix is a better bet. If your company is relying on Exchange services, then you're looking at something like Open Groupware. If you aren't using Exchange clients, but do need similar services, then OpenXchange might do what you want.

That's just for e-mail! Then you have to think about all other intranet services, which have a similar level of flexibility. Internal web services with static web pages will be better off driven by Tux. Java servlets, these days, really mean Apache, as they're the ones mostly working on that capability. Basic scripting with reasonable power and reasonably dynamic content would probably mean Roxen.

If you want virtualization, you've three entire tiers - total machine simulation (vmware), heavyweight containers (xen) and lightweight encapsulation (vservers). If you want to admin the box, do you edit the config files, use Red Hat's scripts, use Linuxconf, or use webmin? And the list of options goes on and on and on.

On the one hand, the choices give an aware user a fantastic level of power and almost superhuman control over their system. On the other hand, it means that you cannot approach this with a turnkey attitude. This should be no great surprise. You can drive a roadcar with a turnkey attitude and expect to get from A to B in one piece. This isn't going to work in a Formula 1 racing car or an X-15 experimental aircraft. Why should it? If you act as though these are all one and the same, your efforts to transfer over WILL fail. This is not a limitation of these vehicles, it is a failure to recognize that simplifications that are true in one case won't hold for the general case.

Let's look at one of the big complaints I've heard for Linux - a lack of wireless card drivers. How many of those who are complaining have actually looked for additional drivers? My guess is that half the complainers have not, and that the majority of those would find that a project just as madwifi would provide the drivers they want. There are a few others listed on the Linux WPA Supplicant page. "But we don't want to install 3rd party drivers!" That wasn't the complaint - the complaint was that the drivers didn't exist. If I can find the drivers, and they DO exist, I will have zero sympathy for those who then come up with further excuses - because if the complaint has to change each time it's proven wrong, then all it is IS an excuse.

My guess is that almost every single case of a company "needing" to switch from Linux to Windows will - on closer examination - prove to be a case of nobody bothering to figure out what the company actually wanted, OR nobody bothering to figure out how to get Linux to provide it. There will be VERY few cases - although such cases will happen - where Linux really isn't a good fit, which is a limitation of Linux, but I seriously doubt that more than one in a thousand migrations from Linux to Windows fits into that category.

My apologies for replying to myself, but...

It appears that the wpa_supplicant guys are putting together a GUI. There doesn't appear to be much information on their website regarding it (such as what versions it's included in), but something's better than nothing.

My apologies for replying to myself, but...

It appears that the wpa_supplicant guys are putting together a GUI. There doesn't appear to be much information on their website regarding it (such as what versions it's included in), but something's better than nothing.

• NUMA - Non-Uniform Memory Access, a step beyond symmetric multiprocessing allowing for more processors and memory local to each processor
• HostAP - appears to be a driver for certain wireless chipsets that allows your computer to act as an access point
• FUSE - Filesystem in User Space, rather than kernel space
• relayfs - a common mechanism for getting large chunks of data out of the kernel safely, apparently for thing like tracing
• securityfs - apparently another pseudo-filesystem that is meant to unify things that are being handled in different ways now.
• DCCP - Datagram Congestion Control Protocol, apparently part-way between TCP and UDP, DCCP provides congestion control without TCP's reliability guarantees. Meant for streaming media, MMORPGs, and other apps that need UDPs timeliness but don't want to blindly flood links

Or setting up their own AP (wonder if this thing can do HostAP...)

What if you pay the $30 and get the signal, and then rebroadcast in the plane using HostAP?

You could even run your own DNS caching etc.

• Important Stuff

If you're using a Prism-type chipset, you can either use hostap (for 802.11b) or the Prism54 drivers (for 802.11g) to run your card in "Master" (AP) mode. Instant linux-based AP.

I play with this off and on with my laptop and the high-powered SMC-2532W-B card, which can take an external antenna. Crank up Apache, set up BIND to return the laptop's wifi IP address to every query, and away I go (hey, wifi isn't JUST for The Internet(tm) after all). Or if I feel the need I can bridge to a wired connection, but that's boring - ANYONE can do that...

Anybody know if any of the 802.11g Prism-chipset-based PCMCIA/Cardbus cards exist that can take and external antenna?

Now I'm not supposing most people would want to set up linux with the hostap driver, and configure their routing, etc. But with some slick Windows-based software, you could do the same thing in a more user-friendly way. Hey, they could even charge double the normal price for the pcmcia WIFI card, and call it a "special access point" card or something.

I fail to see how this is any different (from a linux geek's point of view) from using any prism2-based WLAN card with the Host AP drivers.

Might appeal to PHBs without the necessary 'mad skillz', though, but these are hardly Slashdot's target audience.

The HostAP driver does encryption in software.

My home server is (among other things) a wireless access point. The card I have is a few years old and doesn't support WEP at all, but thanks to this driver it does! In fact it also supports a bunch of other security features for encryption and authentication, which I have not delved into.

That said, it sounds like this new encryption may be at a lower level, which for all I know may necessitate new firmware.

It's based on the prism chipset, for which a variety of excellent Free Software drivers are available. Heck, you can even run an access point or WDS repeater with this dongle... See http://hostap.epitest.fi/ for more information.

My understanding is that an access point tells associated devices to transmit one at a time, in an ad-hoc network devices can transmitt over each other.

As far as I'm aware, you can only do host mode with a linux box using hostAP and a prism card. Is there support for any other cards?

I can run a DHCP server on the router to automate the network layer, but there is no way to set the PCI card in the router so that the laptop automagically picks up the channel and establishes a link.

I have the opposite problem, my linux router box in ad-hoc mode somtimes jumps to whatever channel my windows laptop has descided to use, paticularly if the laptop is turned on first. I want it to stay on a fixed channel. The windows laptop has no option to set a channel in ad-hoc mode (orinoco card) and finds the router on any channel.

With my work, I have hostapd set up with a radius server for authentication. I specifically use x.509 certs, but you could probably use leap, or some other 802.1x.

You might want to try out HostAP.

Their drivers seem to me very stable, and they support 2.6 aswell (N.B. just building one driver with e.g. "make pccard" didn't work for me for 2.6, but building ALL drivers with a simple "make" worked.)

I'm not talking about using the card in HostAP mode (ie. using your wireless network card as a access point). You can do that of course, but I just wanted to recommend these drivers because I've tried all other drivers for prism2/2.5 cards, and none worked for the various non-ix86 architectures I'm using.
The HostAP drivers however work on all of them!

I've been toying with a related idea - but instead of setting up a 'client' system, I was considering trying to set up a portable "access point" and internal "network" in a vehicle.

I find it odd that even today nobody blinks if someone says they're building a LAN and doesn't mention internet access, but if someone says "wifi" it's automatically assumed it's only for The Internet(tm)...

I'm thinking of taking a "scrounged" ancient laptop, Prism 2/2.5/3-based 802.11b card, hostap (is there a hostap-type linux driver for prism GT chipsets yet?), and a trimmed down linux distro running dhcp, dns, and web servers (maybe even Samba) to provide 'local network only' connections to passers by as I travel, just as an experiment. Maybe even some sort of 'chat' facility. (Mainly just because I'm curious how many people would notice, how many people would immediately disconnect when they got the "this doesn't provide internet access" page, and how many would browse the [legally] free downloads, "sign" the guestbook, and so on...)

On the other hand, I'd also like to figure out how to interface with Kismet so as to "pause" it when a potentially-open network is detected and have a script check to see if it's REALLY open (a lot of "open" networks seem to still restrict by MAC address, or aren't running DHCP servers, or otherwise are not designed to be connected to by just anyone) and perhaps "burst" a quick email send/recieve as I drive by before having Kismet resume scanning...

• 
  bttv/v4l patch
  
  bluez kernel patch (bluetooth)
  
  matrox frame buffer patch
  
  alsa 1.0.1 kernel patch
  
  hostap (accesspoint sw for prism hardware)
  
  qc-usb (quickcam express driver)

We've done something similar here in austria, called q/spot. It's a free and anonymous hotspot. We used a Soekris net 14xx Box as a hardware basis (embedded 486) and equiped it with a prism2 capable card. Software that runs on it is a quite homebrew linux it offers us a httpd, iptables, ssh. The Accesspoint setup is done via hostap. With iptables you have full control of your users, even able to limit ip connections and set quotas (good against file sharing neighbours). In our setup the user gets a 30 Minute session. The first http request he sends is redirected to the local httpd showing him the Terms of Useage of this service. There is a log in button on this page, clicked it calls a simple cgi, wich ads the ip to a list of valid ips.
This setup is quite simple and inexpensive. Of course you pay the box and you pay the card, we got the box for free, and paid about $150 for the card. (it's an uncommon prism2 pcmcia card with the possibility to plug in an antenna).
I'd use 802.11b cause i think last meters ain't the bottleneck.

Just apply the Host AP patch and your Prism cards will work just fine.

well, if you're using HostAP, you could theoretically build up a dynamic defense that would mac filter and force disassociation (if an association was attempted) of any station detected to be scanning. you could do similar things with embedded devices and licensed firmware, i'm sure.

Given that they used the linux-wlan drivers, I suspect that this isn't a true AP (running in BSS mode), unless support for this is now in linux-wlan (they do say they use bleeding edge drivers).

Given they use Prism II hardware, I don't understand why they don't use the hostap drivers.

BSS mode has scalability advantages, because it solves the 'hidden sender' problem. ie even though 802.11 nodes always listen to check that the channel is clear before sending, there is a danger that two nodes at opposite extremes won't be able to hear each other, and will try to send at the same time, resulting in collisions. A true AP, running in BSS mode, helps aleviate this problem.)

The wireless group in Houston is building even smaller boxes that are capable of doing everything that this box does. A HOWTO is being assembled here. They are using the Soekris Net4501 in combination with the DWL-520 802.11b PCI card to run Linux and push HostAP and NoCatAuth. The Soekris comes with 3 NICs and no moving parts!