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Odd Lots

  • Cisco has sold their Linksys home-router business to Belkin. I’ve used Linksys gear for ten years now, know it well, and like it as much as I like any given brand. Getting it out of Cisco’s hands, where it had languished, is a good thing.
  • From a long-time Contra commenter I know only as bcl, here’s a very detailed technical review of USB chargers, which are not all the same based on equal output specs.
  • I’m trying to figure out what Ten Gentle Opportunities is “like” (a comp, I think they call it) and have asked those who’ve read the first draft. Someone recommended Piers Anthony’s Apprentice Adept series, which I’ve never seen nor heard of. Will begin looking for copies in local used bookstores.
  • IBM is perfecting an anti-microbial gel that they claim bacteria cannot develop resistance to. IBM. God love ’em–because the way things are going, we are gonna need this, and need it bad.
  • Then again, IBM also says that Steampunk will be the next big thing. Wait a minute. I thought Steampunk was the last big thing. (Thanks to Bill Cherepy for the link.)
  • I’m getting recommendations on surplus dealers I’ve never heard of from all corners. Here’s Twin Cities retailer Ax-Man Surplus, courtesy Lee Hart.
  • Lee also passed along the sad news that Glenwood Sales in Rochester NY, where I spent a great deal of money 1979-1984, is no more.
  • Pete Albrecht sent word of C&H Surplus in Duarte California. I used to have a print catalog from them and it vanished somewhere along the way, but the firm exists and sells mostly industrial surplus (motors, fans, compressors, etc.)
  • I stumbled on a nice free wallpaper site while looking for wood texture images, and there’s a lot of very good stuff there. That said, the single picture they have of a bichon is awful.
  • Bill Cherepy sent a link to a Steampunk workspace. Looks cool. As with most Steampunk keyboards, it looks uncomfortable. Love the tube amp, though it’s not really Steampunk. He needs a new (old?) mouse.
  • Sex with Neanderthals may have ram-charged our immune system and in other ways made us stronger. Genetic diversity is always good. And I’ll reiterate here that I have serious doubts about Homo Sap wiping out the Neanderthals. I think the Neanderthals wiped themselves out. Tribalism is fatal. Make sure your loyalties are diverse. Never throw poop at other tribes. Throw it at your own tribal leaders. If you can’t do that, well, you’re pwned.
  • Cats with jet packs…in 1584. Except I don’t think it’s really a jetpack. Given the bird’s unnecessary jet pack, I suspect that they are acting as living firebombs. The past sucked. I’m glad I’m here.
  • We’ve had a so-so winter so far; could use more water coming out of the sky. However, it’s about to get cold again. Perhaps I could use one of these. (Does anybody else flash on H. R. Giger looking at that damned thing?)
  • There are certified zombie shotgun shells. Haven’t seen Bigfoot flip-flops yet, though.

Odd Lots

  • From the Words-I-Didn’t-Know-Until-Yesterday Department: Fixie, a fixed-gear bicycle; i.e., a bike in which the pedals always move with the rear wheel and coasting is impossible. Fixies are currently the rage among hipsters in stylish cities. It sounds deranged to me, but I lack the hipster gene and value my knees, so what do I know?
  • From Aki Peltonen comes a link to probably the best volcano blog I’ve ever seen. Great photos, interesting analysis, and reasonably courteous comments. (Boy, you don’t see that everywhere!)
  • While we’re talking volcanoes, how are the sunsets in the UK? Denmark? Any personal reports from readers here?
  • Many have sent me a link to the Panoramic Wi-Fi Camera, a fascinating gadget that consists of 20 cantennas arranged in a vertical line on a frame that spins 360 degrees horizontally. Spin the device, and a netbook builds a panoramic image of the 2.4 GHz field in the immediate vicinity. Watch the videos. Fascinating on its own merits, and pay attention to what happens when somebody throws a cup of coffee into a nearby microwave oven: The oven blinds the camera to everything else. For all the tooth-gnashing we hear over cellphone radiation, microwave oven RF leakage never seems to get a whisper.
  • This should surprise no one: Google’s Street View carcams have also been wardriving. There’s less to this than meets the eye (there was a project, now defunct, doing this in 2002) but it’s yet another reason I don’t power-up my Wi-Fi access point unless I need it for some reason. (My house has Cat5E in the walls, and I use PowerLine bricks for high-speed Net access in odd corners.)
  • Dave Schmarder N2DS has given his homebrew radio site a major upgrade and its own domain, so even if you saw it a few years ago, do take another look. Gorgeous work.
  • We blew through the range of SDHC Flash memory cards in record time: 32 GB cards are now in the supportable $60-$80 range…and 32GB is as big as they get. We did this in four years. Admittedly, SDHC was a cheap’n’easy hack, but hell, what kind of damfool memory standard only increases capacity by 16X? (Even SDXC, which takes us to 2 TB, should have gone much farther.) My guess: Standards authors don’t want to be wrong about future advances in hardware, and certainly don’t want to be a drag on future innovations by being too explicit about how hardware is supposed to work ten or twelve years on. I can see both sides. That doesn’t make it any less annoying.
  • From Michael Covington comes a pointer to a 1952 riff on beer and ham radio, and a glimpse of what cash-poor radio guys dreamed of the year I was born. I’ve never met anybody who ever had such a rack (the radios, the radios!) but beer was and remains very big in radio shacks to this day. K1NSS is the cartoonist behind the Dash books, about a dog who does ham radio. (I found him last year while researching names for our current puppy…)

A Viral SSID

First of all, you can stop worrying about me–Carol and I took an intense week-long trip to Chicago tending to family business, and I just couldn’t summon the energy to post while I was there.

But I was reminded of an interesting thing on the trip home, while we waited at the gate for our plane at O’Hare. I opened my new laptop to check for connectivity, and in addition to the airport’s Boingo network, I saw the oft-encountered but poorly understood “Free Public Wifi” SSID. I’ve seen that SSID in airports on almost every trip I’ve taken in the last three or four years, well-aware that it’s not anything like free connectivity. I’ve always assumed that it was a virus running on somebody else’s close-by laptop, because it’s not an infrastructure node like an access point, but an ad-hoc (peer-to-peer) node instead.

Well, it is a virus, but one of a truly fascinating sort. And that may be a little unfair. It’s not malware in the sense of adverse execution on the machine, but a consequence of some Windows foolishness in XP and (possibly) more recent versions. The “Free Public Wifi” SSID spreads virally without the help of anything except Windows itself. I never completely understood the mechanism until I looked it up yesterday. There’s a great writeup here, and I’ll summarize:

Wireless Zero Configuration (WZC) is the part of Windows that manages Wi-Fi connections. When enabled, it will do the following when the machine is booted:

  1. It looks to see if one of your preferred network SSIDs is present in the list of detected infrastructure networks, and will connect if present. Failing that,
  2. It attempts to connect “blind” to infrastructure networks on your preferred list that are not detected, to cover the possibility that your network’s SSID beacon is disabled. This is the Wi-Fi implementation of “security by obscurity,” and no one really uses it anymore. Having failed to connect to a hidden infrastructure node,
  3. WZC will look to see if one of your preferred network SSIDs is present in detected ad-hoc networks, and will connect if it finds one.
  4. Now the weirdness begins: If none of your preferred network SSIDs is present as an ad-hoc node, and if there is an ad-hoc SSID in your preferred networks list, WZC sets your system up as an ad-hoc network with the first ad-hoc SSID it finds in your preferred list.

Hoo-boy. Read that again: If you’ve ever connected to an ad-hoc node and no networks in your preferred list are available, your machine becomes an ad-hoc node. This may not be the worst wireless idea ever, but it’s right up there. Basically, you’ve opened a door to your machine, and (depending on your firewall situation) if somebody connects to your laptop through the ad-hoc node that WZC has created, they can browse your shares.

It didn’t take malware to make this happen. Windows did it all by its lonesome. Here’s a likely scenario explaining why this SSID is so commonly seen in airports:

  1. Somewhere, somewhen, there was a mesh (peer to peer) network named “Free Public WiFi.” It was probably legitimate. I don’t like mesh networks for various technical reasons, but they have their uses, and there’s nothing necessarily scurrilous about them.
  2. An XP user logs into this original “Free Public Wifi” network and connects to the Internet. The SSID is added to their preferred networks list as an ad-hoc node, where it remains. When finished using the mesh network, the XP user breaks the ad-hoc connection and life goes on.
  3. Later on, which could be months or even years, the same user (“User #1”) goes to an airport and while waiting for a plane, boots his or her laptop to do some local spreadsheet work. No connectivity is found, so Wireless Zero Configuration happily establishes an ad-hoc node called “Free Public WiFi.”
  4. A nearby XP user (“User #2”) boots a laptop, looking for connectivity. He or she sees “Free Public Wifi” as an available network, and (naively) clicks to connect. An ad-hoc connection is established to User #1’s laptop. Nothing happens, since neither user is connected to the Internet. However, the “Free Public Wifi” SSID is added to User #2’s preferred networks list. User #2’s plane eventually comes in, and he or she shuts down the laptop, disappointed that no free connection was found.
  5. Later on, User #2 is again at an airport and boots the laptop. WZC establishes an ad-hoc node, and this time, two users see the “Free Public WiFi” SSID and connect. Again, nothing either good or bad happens, but the “Free Public WiFi” ad-hoc SSID is added to the preferred networks list of both User #3 and User #4.
  6. User #3 and User #4 (neither of whom have any idea what’s going on) boot their laptops at other airports, or at conference centers, or some place where laptops tend to congregate. Similarly naive users connect, looking for a free Internet connection, and add “Free Public WiFi” to their preferred networks list.
  7. Contagion continues, as road warriors spread the SSID as explained above.

Although malware isn’t involved, this is far from harmless, since an ad-hoc connection is a door to your machine. Your firewall will probably stop any shenanigans…if you have it working and configured correctly. Some people won’t.

Note well that this only happens if your system has the WZC service running. If you have vendor-specific software installed to manage your wireless subsystem (as all newer Dell laptops do) this craziness won’t occur. Only if Windows and WZC are in charge of wireless are you vulnerable. The solution? Limit your connections to infrastructure networks. There’s a step-by-step at the end of this article.

Other such viral SSIDs exist; I’ve seen “hpsetup” and “default” myself, and others have been reported. Any ad-hoc network SSID can go viral with the help of Windows Wireless Zero Configuration. The “hpsetup” SSID was “contracted” from certain HP printers that connect to laptops via ad-hoc connections. I’ve only confirmed this on XP; the issue may have been resolved with Vista and 7. It’s a fascinating example of unintended consequences in system design, and should become a textbook case in CS coursework. (Why don’t I think that this will ever happen?)

Odd Lots

  • We take digital clocks for granted, but this project may give you some perspective on just how difficult a challenge a digital clock really is. Absent integrated circuits, it takes over 1200 discrete electronic components to make a 6-digit digital clock. And you can get a kit.
  • Maybe RCA’s engineers are having a little fun with us. It’s hard to tell sometimes, but I still don’t understand how this thing is not a hoax. I maybe know a little bit about both RF power physics (37 years in ham radio) and Wi-Fi. If there’s a place in the world with enough Wi-Fi hotspots to make that little box generate useful power, please tell me where, so I can be sure never to go anywhere near it.
  • Several people have noticed that my author bio photo on Amazon has been replaced by someone else’s. Most oddly, the photo is of my old friend Jon Shemitz of Santa Cruz, who’s done some very good books on Kylix and .NET 2.0. I’ve been trying to get Amazon’s attention for a couple of weeks now, no luck yet.
  • did it again: They sent me an email asking whether I’d like to reconnect with a girl from my high school class. As I’ve said before, Lane Tech High was all-male until several years after I graduated, so there was no Teresa Mazzerelli in my class–nor does she appear in the alumni directory. One I could call a database error. Two I call fraud. Don’t give these guys your money.
  • Malt is my favorite ice cream flavor, but it’s very hard to come by. Several companies have offered it in the last ten or twelve years, including Meadow Gold and Boulder, but the flavor has always vanished after a few months. I guess I may just have to make my own.
  • Sprint may be partnering with Wal-Mart to put WiMax nodes on top of every single Wal-Mart in the country. This is not the first time I’ve heard this, and have reported on it before, but having had some experience with something a little like WiMax, I think it could be a huge moneymaker for Wal-Mart if they don’t let the control freaks at Sprint ruin it.
  • From the Words-I-Hadn’t-Heard-In-Thirty-Years-Until-Yesterday Department: bildungsroman, a coming-of-age novel. Why, then, does it suggest erecting a shrine to the Emperor out of cow pies?