The Deliverator – Wannabee

So open minded, my thoughts fell out…

Archive for the 'SWN Hacknight' Category

The (almost) $100 computer

Posted by Deliverator on 22nd May 2007

At recent SWN Hacknights, the NorhTec Microclient Jr. has come up quite frequently in conversation. The Microclient Jr is an extremely small PC with a 200mhz x86 processor, 128 MB of ram, sound, usb, vga, ps2 and all the typical ports one would expect on a PC and is capable of booting from a variety of devices including CF, USB devices, hard disk and even PXE network boot. The small size of this device (it can even attach directly to a VESA standard mounting bracket like…the back of a monitor), good connectivity options and rock bottom price make it a very attractive platform for embedded projects, thin clients and other assorted hijinx.

Norhtec Microclient JR Interior

The Microclient Jr is available in a couple different configurations, including one with a wifi card and/or two serial ports. The Microclient in its most basic version sells for $120 in small quantities, but supposedly this shrinks to $90-100 in sufficiently large quantities. Given that NorhTec ships their units from Thailand, the $40-50 shipping cost for small orders really eats into the platform’s attractiveness. Thankfully, I found out that the Microclient JR is also sold rebranded as the eBox 2300 and is available via a couple US distributors. Not only does this cut the shipping cost and time down significantly, but most of the distributors are selling it even cheaper than Norhtec. I ordered mine from WDL Systems with two serial ports and an open mini-pci slot (for self installed wifi) for $150 with two day shipping. Both Northtec and WDL Systems sell the Norhtec in a configuration with WiFi preinstalled, but their solution is based on a VT6655 chipset, which has poor compatibility with Linux 2.6 series kernels, so I chose to leave the slot open and add something with better support.

I look forward to receiving my Microclient JR soon. I have a number of projects in mind for which I believe it should prove suitable. If so, I will probably be purchasing a few more.

Addendum – Ordered a Ubiquiti XR2 mini-pci card and pigtail from Matt’s company, Metrix.

600mw Ubiquiti XR2

Amusingly, these two items cost more than the computer itself. The card is rather expensive at $130, but it has a lot of novel and even unique features including:

-600mw transmit power. Most previous generation “best of breed” cards like those from Senao maxed out at about 200mw. By contrast a lot of the solutions integrated by OEM’s into laptops are in the 30-80mw range. This card is the current reigning Border Blaster of 802.11.
-Excellent receive sensitivity…just because you are blasting 600mw out to the AP doesn’t mean it is blasting 600mw at you :)
-Uses a more robust mmcx connector. Most mini pci wireless cards use a much smaller Hirose/U.FL connector which isn’t as mechanically robust. In fact, the manufacturer only rates U.FL as good for 30 couplings, and that is assuming you don’t break the connector by tweaking the cable to which it is connected. I would prefer cards used something even more mechanically secure, like some variant of SMA. I saw this option advertised for the Ubiquiti cards at Linux Devices, but Matt has never seen it actually sold that way.
-The card is supported by the excellent MadWifi driver under Linux. This driver lets one do some pretty spiffy things with this card, such as creating multiple virtual access points and adjusting channel size (allowing one to have more non-interfering channels or alternatively use up more of the band for more throughput potential).

I look forward to playing with the eBox 2300/Microclient JR and the Ubiquiti XR2 card next week at hacknight. I hope they play well with each other. My main concern is whether the eBox will supply the card with adequate power for its 600mw transmitter.

Posted in Portable Computing/Gadgets, SWN Hacknight, Tech Stuff, Wireless | 7 Comments »

OLSR now available for DD-WRT!

Posted by Deliverator on 2nd May 2007

Brainslayer, the one man band behind DD-WRT, an alternative firmware project for wireless router, recently announced some pretty cool news. As of today, he is integrating OLSR into DD-WRT and making it available for all devices capable of running it. OLSR is a mesh routing protocol that allows one to easily deploy large wireless networks with a minimum of fuss. A (greatly) simplified explanation is that you can throw out a bunch of wireless access points and they find each other and figure out how to route traffic on their own so that everyone can talk to each other and the internet, regardless of whether a particular node has its own individual DSL connection. OLSR has been used successfully to build some very large networks, perhaps most notably the Freifunk community wireless network in Leipzig, Germany. This network currently has over 500 nodes connected to the internet and each other using a standardized platform of inexpensive Linksys WiFi routers (available for $50-60) running OLSR using their own custom firmware, based on OpenWRT. The node map for their network is REALLY impressive and I so want to have it as a poster!

Freifunk Node Map

I greatly prefer DD-WRT to OpenWRT, so it is nice to see that OLSR is being integrated into DD-WRT as a standard option and made easy to configure with its own configuration page in the web page based admin tool. DD-WRT is available for a wide number of inexpensive and even FREE devices and I can’t help but think that this is going to make it much easier for neighborhood and community wireless network to succeed.

Posted in SWN Hacknight, Wireless | No Comments »

More Fun with Fon

Posted by Deliverator on 22nd March 2007

I had some more fun with my La Fonera this week. As in my last post, from hence forth the La Fonera shall be simply known as the lwb. The week started off with my lwb in a bricked condition thanks to an attempt to flash a new daily build of dd-wrt onto the device using the web interface over a wireless connection. Thankfully, I was able to still access Redboot after bricking my lwb and was able to flash to the version of dd-wrt from 0319. I heartily recommend that once you get your lwb up and running with dd-wrt, that you use ssh to flash to future version and not the web interface.

You can flash to the latest version via ssh by doing the following:

cd /tmp
wget <newest version of root.fs>
wget <newest version of vmlinux.bin.l7>
mtd write vmlinux.bin.l7 vmlinux.bin.l7
mtd write root.fs rootfs
reboot

Anyways, once I had my lwb unbricked, I was eager to try a rather neat feature present in 0319, the ability for the lwb to act as both a client to a wireless network as well as act as a wireless router….at the same time. Pretty neat trick for a device that only has one radio, eh? The lwb is capable of doing this juggling act thanks to its Atheros radio. I recommend upgrading to 0319, as this feature has been broken in many of the recent daily builds. Supposedly, the build from 0310 will work as well.

So, why would one want to do this? For one, it allows one to create a “repeater” for an arbitrary wireless network which may not quite reach to where you want its signal. It does it in a way which is compatible with security systems like WPA, unlike WDS repeating, which requires special set up and has a number of undesirable technical limitations. With the lwb, it is possible to create multiple virtual ap’s and create different rule sets for each.

I tested this single radio repeating at Hacknight this week, connecting as a client to the the internet cafe’s wireless network with the lwb acting as a wireless access point with routing as well. In this mode, the wired port on the lwb which is ordinarily used for wan connectivity acts as routed port, enabling wired devices to join in the fun. One can also put the lwb into a bridging-client mode, where the lwb acts as a wireless client and transparently passes traffic to the wired interface, but I haven’t tested this yet. This can be useful for connecting NAS appliances, network printers and other conventionally wired devices to your network, without any real limitation as to where you can place them. Don’t have enough room in your office? Put the printer in the linen closet! Wireless bridges really let one unclutter one’s environment.

I did one little last bit of hacking on my lwb this week. Erik Butler commented on a video he’d seen on YouTube in which the plastic casing of the lwb had melted due to the heat. The lwb is a *little* white box and doesn’t have almost any ventilation. A number of users on Fon’s own forums have commented that their units seem to be overheating and spontaneously rebooting as a result. At least two people have explored this issue in a pseudo-scientific like manner. The general conclusion seems to be that the ventilation in the lwb is woefully inadequate and that the high temperatures are likely to result in a drastically decreased operating lifetime, with the likely cause of death being capacitor failure. I have definitely noticed that my lwb runs quite hot, so decided to protect my investment of 0$ by adding a fan to the unit. I managed to scrounge a fan from an old motherboard chipset cooler which was of an appropriate size and voltage rating and with the help of my soldering iron and dremel tool, was able to add it to the lwb. My lwb now runs MUCH cooler, with no appreciable heat build up.

Posted in Linux, Rants and Raves, SWN Hacknight, Tech Stuff, Wireless | 2 Comments »

Seattle Wireless Hacknight – 11/22/06

Posted by Deliverator on 24th November 2006

Most of the guys at Hacknight spent the evening working on a bunch of Arlan 900mhz radios purchased from Ebay. These are wireless devices that predate the 802.11 standard and date from about 1994. The devices all came in access point mode, but some clever use of the Internet Archive revealed a method to convert them to bridges by applying a particular sequence of firmware upgrades and downgrades. A few of the devices were bricked in figuring out the proper process, but it seems like most of the kinks have been worked out now. The Arlan devices only cost about $20 each (compared to modern 900 mhz devices which cost 400+), so nobody is too discouraged about a few bricked ones. The intention is to use these to test the feasibility of linking nodes which for whatever reason can’t be linked with 2.4 ghz radios, such as near line of sight scenarios where dense foliage or a building might separate two isolated nodes. If a link can be established using these old, slow (.5mbit) 900mhz devices, then it should be possible to simply swap in newer (read – expensive), high speed 900mhz gear. At $20, it is a cheap way to test the viability of a link and hey .5mbit is useful in its own right.

A nice guy named Joseph stopped by our table and asked us about what we were doing. Turns out he does a lot of low level system designer/engineer and has a lot of experience with the Motorola 68k family of processors which the Arlan devices use. He is going to try and stop by next week to disassemble some code and provide some more details on the boot process. Hopefully, he might be able to find a way to debrick a few devices, or find an easier way to convert them over to bridging mode. He used to work for Psion and we talked for a while about my Psion Netbook Pro, Nokia 770 and the upcoming 870 (presumed name). He was very disappointed over what has happened to the company over the years, in particular the switch from the EPOC OS (arguably the most stable, robust OS ever featured on a palmtop) to Windows CE.

Ken tested some high power, 400mw mini-pci 802.11g radios from Ubiquiti Networks using a Soekris board. This is a particularly neat radio as it is high power, has excellent receive sensitivity, uses an Atheros chipset supported by the MadWifi driver under Linux and has both MMCX (yay!) and u.FL connector. MMCX is considerably more robust connector, mechanically than u.FL. It also appears that this card is available with an optional SMA connector, which would be better yet. Ken has some doubts as to whether two of these very high power cards will run happily in a low-power Soekris boards, but I expect these cards will find a lot of useful niches.


Matt Westervelt
and I both purchased new lenses for our respective Nikon DSLRs, but have yet to receive them. I purchased a Sigma 30mm F/1.4 and Matt purchased an MC Zenitar 16mm F/2.8 fish-eye lens on eBay from Kiev Camera. This Zenitar fish-eye is one of the cheapest wide-angle lenses currently available at around $150. The lens is made by KMZ which has been making all sorts of optical products since WWII. This lens is strictly manual and the build quality is probably about what you would expect, but for $150 it is probably the cheapest way to experiment with a fish-eye lens. People seem to have a lot of fun with this lens and Flickr has some interesting examples of what can be done with it. I might pick one up once my budget has recovered somewhat from all my recent camera related purchases.

More pics from Hacknight available in the gallery.

Posted in General, SWN Hacknight, Wireless | No Comments »

Seattle Wireless Field Day 2006

Posted by Deliverator on 28th October 2006

EDIT Other participants have started writing up their Field Day experiences here, here, here and here. I especially liked Casey’s Field Day Video.END OF EDIT

Spent the day at Don Armeni Park at Alki Beach as part of Seattle Wireless Field Day 06.

SWN Field Day is an emergency preparedness exercise (and all around good time) conceived of by Casey Halverson. Field Day evolved from the observation that quite often natural disasters cause severe, long term interruptions/disruptions in city scale infrastructure, particularly communications infrastructure. This was very evident in the case of Hurricane Katrina. The basic idea of field day is to get a bunch of people and their gear together and establish wireless network (and internet) connectivity spanning physically disparate areas of the city. The idea of leveraging wireless technologies for disaster relief isn’t exactly new. Amateur radio operators have a decades old annual preparedness event of the same name. What is new is the ability to leverage commodity hardware, open source software to provide high speed data connectivity. Volunteers from several community wireless groups descended on Louisiana after Katrina and quickly established a routed, wireless network, providing Internet connectivity to many schools, public buildings and shelters. You can see some pictures of Katrina related wireless efforts here. Even second hand, it was amazing to see valuable services like VOIP and user created “family member location” databases emerge; not out of governmental forethought or rapid (ha) mobilization, but from intelligent people in need using the tools available to them.

Antennas Field Day 06

I arrived a little after noon to Alki and found Ken, Erik, Galan and Casey already set up with a tent, laptops, antennas, cabling, batteries, inverters and other assorted equipment. Erik used my car-puter’s EDGE internet connectivity to download some important bits, including the OLSR mesh routing protocol onto his laptop. Soon after, we returned to the tent and Ken and Erik were able to establish wireless links across Elliot Bay to downtown Seattle and Magnolia. The Gasworks site was a bit of a bust due to late arrivals from several key people, as well as a lack of adequate power provisioning. Most of the people at Gasworks moved over to a marina on Elliot Bay where connectivity to Alki was eventually established. Coordination of activities occured using FRS/GRMS radios and proved adequate (and only just adequate) to the task. Once all the sites were up an running, people chatted on IRC, spoke using various standalone and software based VOIP phones, streamed radio and watched the latest silly videos on YouTube. Aside from random hardware related hijinx, I would say that establishing and connecting the sites proved easier than in past years, in no small part due to OLSR handling many of the routing details. Ken took a number of screenshots of network maps during the day and they were quite impressive to behold.

OLSR Field Day 06

The only low points for me were:

-It was a beautiful day, but too damn cold (I am still cold after several hours bundled up in my bedroom with the space heater turned on high)
-Not enough chairs
-No on site food

All three of these complaints could be solved if only I had:

-Dressed in more layers, worn a hat and gloves
-brought my own damn chair
-brought a thermos and some snacks.

In short, the only negative aspects of field day for me were my own fault. Field Day is most certainly a participation oriented event and I will just have to be more “prepared” for it next year. I do hope we are able to get better organized ahead of time and hold it when the weather is both warm and clear. August would be nice, because as you know, disasters only happen in August in Seattle :)

I am uploading pictures of today’s events now and they will be available at my SWN Field Day 06 Gallery shortly.

Posted in General, SWN Hacknight, Wireless | No Comments »

SWN Hacknight – 101106

Posted by Deliverator on 11th October 2006

Fought my way through traffic to get to Capitol Hill this evening for SWN Hacknight and was glad I made the trip.

-Rob brought the first print copies of his new book How To Accelerate Your Internet, which cover many aspects of bandwidth management. You should be able to buy a print copy shortly. The full book is available for download under a Creative Commons license.
-Got to play around with a Sony Reader. The Sony Reader is Sony’s second stab at creating an ebook reader which uses an electrophoretic (aka eink) display. The first was the Librie, which was only released in Japan. I found the device interesting, but not suitable for my uses. I think I am going to get the Irex Iliad instead.

What Sony got right –

  • High contrast display with amazing off axis visibility. As one person said “It looks fake”
  • Excellent hand-held ergonomics. Easy to flip pages/navigate menus using one hand in either portrait or landscape orientation
  • Easily navigable interface
  • Integrated leather(ish) screen cover, which snaps to the back. Unit feels very “solid”

What they got wrong –

  • This is really designed as a “closed” device, so what Sony wants is what you get. GPL covered code has been released, but many aspects of the device and accompanying software are still very buttoned up.
  • Limited internal storage without relying on a SD card or *surprise* Sony Memory Stick
  • Limited format support and reliance on closed source PC only conversion software for most document formats. Unsure of quality of conversion. We were able to read a PDF file from a SD card, but there was no evidence of read-ahead rendering of pages. Page flips were quite slow as a result
  • Screen resolution is fairly low and is only 4 shades of grey. Trying to read text in PDFs was awefully squinty due to this in combination with the paperback sized screen. I think a device like this will have its greatest initial appeal to engineers, lawyers and other people who work in documentation heavy professions. I don’t think a lot of people will buy a $350 ebook reader to read the latest Danielle Steel bodice ripper.
  • Screen exhibited a distracting degree of ghosting left over from the previous page. Rob described it well as “like seeing the letters written on the opposite side of a sheet of paper.”
  • Sealed, proprietary, internal rechargeable battery. Devices with non user serviceable/replaceable batteries have become a major turn-off for me.
  • Screen orientation can be switched, but it is burried several menus deep in the interface. I constantly shift around while reading and being able to change screen orientation quickly is a big deal to me. My Rocket Ebook has a dedicated button to change orientation. Addendum – Looks like one of the buttons if held down for five seconds will flip the orientation. Still not as nice as a dedicated instant switch button.
  • No touchscreen, so no ability to sketch or annotate or documents.

-Matt brought a Chumby. It is cute, soft and designed to be hacked. Whats not to like? Strangely, my first and ongoing reaction is that I want to pick it up and throw it through a window.
-Rob, Casey and Erik hacked away at getting UAE to play nice with some Amiga ROMS in order to get a unique program called Algomusic to run. Algomusic generates Techno music algorithmicly. It is extremely configureable and it sounds like nothing has ever been created since that quite does the job as well. Rob wants use it as background music for an audio stream featuring text-to-speech renditions of random LiveJournal blog entries.
-Casey did a few announcements relating to the rapidly approaching SWN Field Day. There will be a practice link set up this Saturday across Elliot Bay to get out as many kinks as possible prior to the actual event.
-I got OLSR installed on my Nokia 770.

Posted in General, Portable Computing/Gadgets, SWN Hacknight, Wireless | No Comments »

Curbside Computers

Posted by Deliverator on 19th May 2006

This past Wednesday, I attended SWN Hacknight for the first time since the changeover from Redline to Caffe Vita. Along for the ride was Theo, who has spent the last few years in Iraq and Korea, where Uncle Sam has put his intellect to work pumping gas and pounding fenceposts into the ground. He is kinda/sorta out of the military for the moment (unless they Shanghai him back in using “Stop Loss,” a despicable policy that flys in the face of our all “volunteer” military). He is considering going back to school for a CS degree, or trying to find employement in the IT industry. For the moment, he has a few months to consider his options, and is taking a much deserved breather.

We met up at Cafe Vita, but didn’t stay there long. The weather was beautiful and Matt suggested we move to the park. On the way out the door, someone spotted a pile of odd looking, cracked open computer cases sitting on the sidewalk. Most had been stripped of hard drives, ram and other useful parts, but there were a fair number that were more or less complete. Several of us rummaged through the pile for a few minutes to discover what they might be. The case said “AXIS Digital Media Manager” on the front and Matt recognized that they had stickers from a company called DMX, whose offices are a few blocks from the cafe. DMX is a Muzak type company. The devices we found seemed to have originally been used to stream elevator music over the internet to retail establishments. The device seemed to be more or less a normal pc, with 2 eide ports, a floppy port, sodimm slot, low profile NIC, modem, and a Cyrix 5×86 class processor all crammed inside a black “shelf” case with some front mounted control buttons and a 4-5 line LCD. I figured if nothing else, I would find use for the low profile NIC, tiny power supply and LCD at some point. About half of us headed to the park carrying our found treasures. While on the way to the park, we passed the DMX offices and discovered that their dumsters were half full of similar devices.

Once home, I plugged in a keyboard, mouse and monitor, added some ram, floppy, hard drive, etc. and fired it up. The devices use a bios from General Software, a company which specializes in custom bios software for embedded computers. I was able to get it to recognize the hard drive and floppy disk, but not the cd-rom. I didn’t try to hard. I tried getting Debian and FreeBSD running using network boot floppies, but both experienced some sort of kernel error relating to bios rom caching. I tried turning off caching of the referenced memory segments in the bios, but to no positive effect. Anyone have any clues? I haven’t been able to dig much up about these devices online, and if I am not able to figure it out in a short ammount of time I am going to canabalize mine for parts and throw the rest to the curb…

Click the image below (taken by Matt) to be taken to a small gallery of images related to this funky little device.

Axis Digital Media Manager

Posted in General, Linux, SWN Hacknight, Tech Stuff, Wireless | 4 Comments »

SWN Hacknight – 020106

Posted by Deliverator on 1st February 2006

Eric Butler and I showed up to Hacknight a bit early and were waiting close to an hour before anyone showed up. Hacknight has been canceled at the last minute a number of times in the past, but this usually results in a flurry of emails to the listserv. Between the two of us, we found Casey’s phone number and found out the story.

Turns out the new tower node, Node Atoys had gone down for some unknown reason. Matt, Rob and Casey did troubleshooting for most of the day, swapping radios, settings and testing various theories. In the end, a spectrum analyzer hooked into a directional antenna revealed a high power source of interference coming from the tower. It looks like it may have been a harmonic from some TV gear on the tower. The main transmitter on the tower outputs something like 16KW. That is huge when compared to the 400 mw output by Node Atoy’s Senao card. With the right antennas, sensitive receivers and favorable atmospheric conditions, Hams have been going hundreds or even thousands of miles on similar power. There is even a subculture devoted to the art of long distance RF communications on ultra low power, known as QRP. Of course, some people take different approaches.

Rob had a print copy of his new book, Wireless Networking in the Developing World. The earlier problems with Lulu’s interpretation of the PDF format have been corrected, so get your copies now! The book comes just in time for Rob’s trek to Trieste, Italy for a conference at which he has presented the last couple of years. It looks like he will be gone for about a month. Trieste sounds like a fun place to kill some time. Rob loves good coffee and his favorite brand is grown there. Last weekend at the ROV conference, I saw the submarine Trieste that went some 35,798 feet deep in the Atlantic and came back to tell the tale. By contrast, most military submarines can go something like 800-1000 feet deep, I believe. Don Walsh, one of the two men to make the record setting dive is going to be speaking at the Naval Undersea Maritime Museum in Keyport in a few weeks.

Eric and I are going to grab a 24 db parabolic dish from Casey and do some site surveys from the Eastside to see if we can connect to the tower. If anyone has a house that can see the towers on Capitol Hill and would like their home/biz to be a node on the Network, put yourself on the node map. We are happy to drop on by and see what we can see.

Posted in Mobile Blogging, SWN Hacknight, Tech Stuff, Wireless | No Comments »

Seattle Wireless Hacknight – 012506

Posted by Deliverator on 25th January 2006

Headed to Seattle a bit early today. I was originally going to bring along Larry Barello to talk with Matt and Rob about various OEM wifi modules suitable for use in some very hush-hush embedded systems, but he was feeling rather tired after spending the last few weeks in his cold garage working on this year’s FIRST robot. I will have to drag Larry along next week. I arrived almost an hour early, so I spent some time talking to my brother Scott while waiting for others to arrive, which they soon did – and in large numbers. Tonight’s hacknight ended up being the most populous I can remember in recent history.

Rob showed up with copies of his new book, Wireless Networking in the Developing World, hot off the presses from Lulu. Lulu is one of the first companies to do “Just In Time” publishing. Got something you want printed? Send em a PDF and $10 and a week or so later a nicely bound dead tree edition magically shows up at your doorstep. That is the theory, anyways. Unfortunately, Lulu wasn’t too happy with one of the chain of free tools Rob used to create his PDF, in particular the embedded fonts. Rob ended up with a beautifully formatted book filled with gibberish text that bore a distinct resemblance to Kanji. Rob spent a good chunk of the evening using Lulu’s “live chat” technical support to get the problem fixed before anyone did something rash – like order 150 of the things :)

Rob also showed off his $100 Wi-Spy 2.4ghz frequency analyzer. It is now supported by Kismet in text mode, and graphical support for OS X is otw. Rob tried to get an early version of the graphical version going, but it kept exiting after running for a second or so. We ended up borrowing Casey’s laptop and played around with the official Windows software. It was pretty cool to “see” bluetooth and get a sense for just how much noise is floating around the 2.4 ghz band. At $100 it is a fun toy, although it would be much more useful with an external antenna port.

Matt has announced that the new node on the UPN (now UPN/WB?) tower will be put up this Friday at 8am. I am very enthused about this new node, as it is the first with real potential to link the Eastside into the network. I may even consider climbing the huge tree in the front yard to get line-of-site. Nothing is going to drag me out of bed at 8 am, though…

Casey showed up and showed off his paper wireless sliderule and spent most of the night hunched over his laptop working on a Excel spreadsheet inputting specs on various pieces of wireless gear. He seemed a little withdrawn. I hope he is doing alright.

Matt Wilson showed up in his brightly colored motorcycle garb and brought along some interesting retro hardware which consumed most of his attention for the evening. The chief focus of his attentions was an Apple eMate 300, a large clamshell computer designed for use at the gradeschool level.In concept it is somewhat similar to the Branium Wibook that I brought to Hacknight some weeks back. Matt Wilson brought the eMate in because it late model version of the OS powering the Apple Newton PDA. Matt Wilson is a big fan of his Zaurus PDA, for which a newton emulator is available. Matt spent most of the evening searching poorly organized Newton related archives in search of a debugger. He eventually found a suitable debugger, although it needed to be run from OS 9. Not to be outdone, Matt wipped out an old powerbook (upgrade to a g3 running at ~200mhz on a 33mhz bus). By the end of the evening he had managed to download the rom image to the old OS 9 running Powerbook, transfer it over to his much nicer OS X Powerbook and get it running in an emulator. Although he carried a very sizeable kit of tools on his motorcycle to pry the OS image off the eMate, he forgot his very pocketable Zaurus at home, so that part of the project will have to wait till later. I have collected quite a few obsolete…, make that “retro” pieces of hardware over the years, so I definitely can sympathise.

Spent some time conversing with Schuyler Erle, one of the co-authors of O’reilly’s Mapping Hacks and co-coder of the Nocat captive portal system. Schuyler is visiting Seattle for a week from Boston, courtesy of MSN. MSN has been trying to bolster its map related offerings, after taking a beating from Google Map/Google Local/Google Earth, etc. I should have taken the opportunity to pick his brain about cartography, a subject on which he is quite an expert, but had some interesting conversations with him about a variety of other topics instead. I enjoyed talking with him about an abortive project of his, a p2p filesharing system designed with the network limitations of wireless networks in mind. One of the chief goals of his project was to avoid the huge drop in bandwidth associated with many clients attempting to transfer large files simultaneously, resulting in frequency contention/packet collisions. His system was somewhat similar to Token Ring, implemented at the application layer. I introduced him to Eric Butler, who has been working on a WASTE like private p2p network called Meshwork. The rest of the evening was spent discussing MONO development and the virtues of various programming languages. Oh, btw, in case you haven’t heard, Microsoft Sucks :)

Pics here.

Posted in General, SWN Hacknight | No Comments »

Super Cheap 802.11a Access Points

Posted by Deliverator on 24th January 2006

802.11a is a wireless standard that hasn’t made as much of a splash as 802.11b & g gear. The 5 ghz band that the 11a standard uses has much less penetrating power than the 2.4 ghz that b/g equipment uses. Buildings love to eat .11a signals, requiring great number of access points to be deployed to cover a given area than with b/g gear. As such, 11a gear hasn’t caught on to as great an extent and is now available cheap through many surplus outlets. Given 11a’s inability to break out of a paper bag, why would you want it, even if it is available cheap?

There are a couple of good reasons, in my mind. For one, 11a gear is just as fast as g gear. Two, 11a gear uses frequencies that are not as heavily used as the 2.4 ghz band that is used by cordless phones, security cams and wifi gear. It is getting awefully hard to find free unlicensed spectrum in urban environments. I have personally been in places where my carputer has been able to see 30+ wireless networks simultaneously. That is a hell of a noise floor! Thirdly, because 11a gear uses such high frequencies, the wavelengths used are correspondingly shorter than b gear. That means you can create much smaller, high gain directional antennas. 11a gear might not be such a bad idea when you need to establish a high bandwidth connection in an noisy urban environment.

At last week’s Hacknight, Joe Towner brought in some corporate quality 802.11a access points made by Intel. He bought them for $4 each from surpluscomputers.com. I purchased three to play around with using my Jornada and internet access courtesy of t-mobile. Half the guys there were running packet sniffers and Ken was feeling particularly hacktastic after just getting back from Shmoocon (of which he is an organizer), so I wasn’t about to trust my credit card number to the unsecured wireless network at RedLine. Of course Ken just went to work for t-mobile (doing network security), where he will hopefully help close a few of their gapping security holes, so he could probably sniff my data anyways.

The access points arrived today, which was rather quick for such cheap shipping. I have been playing with it this evening. Initial thoughts:

  • Cool = software selectable antenna pattern (omni or 180 degree sector)
  • Not soo hot = need tftp server to flash the firmware. I used a free one from the aptly named weird solutions.
  • Cool = Has two mini-pci slots inside. One is filled by an Atheros mini-pci 802.11a card. The other can optionally be filled with an 11b card to turn the access point into dual mode ap.
  • Cool = Early reports show a high potential for hackability. The device has 16 MB ram and 8 MB of flash and a Motorola processor of some sort.
  • Not so much = kinda funny shape for an AP. Indicator lights unlabeled.

Posted in General, SWN Hacknight, Wireless | 1 Comment »