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Forget GPS, Hello WPS
No France writes "A company known as skyhook wireless has announced the commercial availability of its Wi-Fi Positioning System, or WPS. The company has compiled a database of every wireless access point it can find in a given city. When a mobile user running th Skyhook client is in a recorded area, their position is calculated by selecting the surrounding signals and comparing them to the reference database. Currently there are 25 US cities mapped, including New York City, Boston, Chicago, Los Angeles and San Francisco. Apparently this device is accurate to within 20-40 meters, though one has to wonder how well it deals with people moving their wireless access points."
All this effort to develop technology to determine your location is great if the reason for finding your location is because you're lost. But, otherwise, it seems like another case of the technology industry developing a new market for devices of questionable usage. Throw legitimate privacy issues into the mix - generally in the US at least and certainly elsewhere - the thought of some anonymous entity determining my location is positively horrifying. I can't help but think that this is one of those situations wherein the instrument precedes any of the truly challenging work of determining sensible, useful applications. (If one more dull-headed marketing guru uses the example of Starbucks ringing a phone as I walk by..) Why is it so difficult to simply self-identify my location rather than relying on the sketchy availability of GPS satellites or databases of WiFi APs and doing all that trigonometry. Here I am standing at 44th and Broadway, based on my profile and previous activities, give me some insights into other activities in the area? Or, are any of my friends within 6 blocks of me? PDPal was a project that provided a map and allowed you to target your location - easy-peasy. Dodgeball goes a light year beyond this, using technology that nearly everyone has in their pocket - a cell phone. No GPS, no WiFi positioning hacks, just a cell phone SMS. Is it because discovering application proves so difficult that the cart, burdened with gizmos, leads the applications cart?
Only three remote holes in the default install, in more than 10 years! OpenBSD
They might as well give everybody a peice of paper with a huge X on it that says 'You are here'.
...and you can geocache with this how?
PORN
PORN
PORN
PORN
20 - 40 meters? Who will be forgetting GPS with that kind of crappy accuracy?
I work for this company, collecting positioning data. Let me tell you, it's a slick setup, and they have a very novel idea for positioning.
Assuming people don't get swap-happy and trade access points all over the place, the reliability should be very high, too.
PlaceLab has been doing this for a while, and it's free.
Martin May
Apparently this device is accurate to within 20-40 meters
Hell, I can guess where I am to that accuracy. I thought GPSs where accurate within 5-8 meters nowadays. And this sounds really useful out in the open ocean, you know, where all those rouge wireless access points hang out.
Measure once, cut twice
20 to 40 meters of accuracy? I work with various grades of GPS and even with low accuracy gps I can get within 10 feet no problem. I mapped wireless access points before and they really turn out to be VERY inaccurate overall.
Oh well maybe some fun could be had, like PHYSICAL address spoofing.
If you're in a major city, you seriously don't need GPS or any positioning system. Look out the window of your car, ask someone, etc. GPS is needed and useful when you're NOT in the city, when you're out in the middle of nowhere or on a highway getting lost. Cities are the one place a positioning system is useless, so why develop it there?
Rather than trying to maintain a static database of AP locations and signal strengths, they should just put some live wifi nodes out there with real GPS on them and track the AP map in realtime as it shifts. Or they could give free service to a select small percentage of customers in return for attaching a GPS device and helping recalibrate the map with some background software once a month or something.
11*43+456^2
looks like this is already being discussed over at wigle.net
Only accurate within 30-40 metres... pffft! Why not use JASYKPS (Just Ask Someone You Kultz Positioning System) - it's free and very accurate. (Note this system fails dismally when no-one else is around)
It's no wonder the technology is only accurate to 20 to 40 metres. GPS uses multiple satellites that are hundreds or thousands of kilometres apart, plus very high timing accuracy (provided by atomic clocks on the satellites), to produce accurate measurements of position. Whereas WiFi can only get baselines of tens of kilometres at best, and I don't know what kind of timing accuracy they can get, but it's surely no better than what the GPS satellites can provide.
Forget GPS
Weeeeeee! This mean we can nuke the GPS stationary satellites now? ''Shut 'em down guys!''
Who said that they, in fact, knew the exact position of every access point to begin with? Who cares if the known APs get moved, they most have accounted for that anyway.
Cue karma-whoring privacy concerns in 3...2...
"Derp de derp."
I honestly would expect it to be even worse.
If this determines position by signal strength wouldn't it then be dependent on the type of antenna you were using with your WiFi card? Sometimes my signal moves around even in the same position or drops significantly lower in "dead spots". What if I'm using one of those crazy Pringles can antennas?
"Hey! 100% signal here, I'm here, over there and...yep, that a ways too!"
Anyhow, what an awesome idea, I mean, it's not like we have anything like this in existence, you know, that millions and millions of dollars were put in to launch satellites into orbit. No, nothing like that, nothing that has 10 feet or less accuracy. Guess we should all start usin this POS. No thanks.
though one has to wonder how well it deals with people moving their wireless access points.
And thats exactly what it will not catch on. No company in their right mind would make products that counted on devices that aren't guarenteed to not be moved. Although it might work if the WiFi APs received GPS data and then acted as base stations to enhance the resolution of your GPS device. What I'd really like to see if GPS that worked in buildings and underground.
Road naming is non-existant outside major thouroughfares; it works more by an irregular grid numbering system of blocks, not the roads in between them. House numbering is similarly vague, with no guarantee that house number 2 will be beside number 3 or 4. Block nameplates are usually pretty small and not in easy-to-predict places very often; GPS, even for pedestrians, is very useful in Japan. Even the taxi drivers haven't a clue where most places are!
. . . but I suspect ultimately of little practical value. Having done quite a bit of RF scanning on the WiFi bands in one of their listed cities (San Francisco) I've seen first hand how signals behave in that dense urban environment.
GPS and WAAS operate on time signals and highly accurate positioning. Cell towers would be inherently more accurate since thier positions are accurately known and don't change (except under very unusual circumstances.
WiFi nodes come up and down constantly, and their position is rarely going to be accurately known by anyone but the person who installed it - and chances are they're not telling "you" exactly where the node is.
Given "walk around surveying" to map the nodes, it's not really a surprise they have accuracy that's no better than an early 2 channel GPS receiver.
And, as others have pointed out, if I'm in downtown San Francisco (or any other city) I don't need my GPS to tell me I'm at 5th and Townsend. For directions there's Mapquest, Google, Yahoo Maps, etc...
Interesting technology. But it sounds more like something a hobbiest would come up with than business.
Never attribute to malice what can as easily be the result of incompetence...
Basically, the military figured out how to easily jam GPS in an area. But before then, there were GPS field units available that averaged out the error and got better than 2-3 meters so that it didn't really matter that much...
Don't these people realize how accurate GPS positioning has become?
MGIS-grade equipment can now give positions with sub-foot ( 30cm) postprocessed accuracy. Survey-grade equipment can get within 5-10 cm.
As neat as WPS sounds, I don't think that anyone will be giving up GPS soon if WPS can't get any more accurate than 20-40 meters.
"Equal bytes for women!"
Sometimes a new technology comes along, and you just have to say WOW! THAT IS COMPLETELY UNNECESSARY!
I'm currently surrounded by the SSIDs, "linksys" and "default". Can someone tell me where I am?
Doesn't it make more sense to use the signals off of Cell towers? They are much more powerful, and fixed point.
Read more at this site...
Sometimes reality is better than you know... ;^)
Could you do something like this in your house? I know this sounds a bit crazy but I am trying to figure something out so I figure out where my roomba is inside my house. That way I could send it to rooms that get more traffic. This would require more hacks for Roomba but I got a good idea how to do that what I need is a way to figure out where Roomba is in my house.
just because your a schizophrenic doesn't mean people arn't really out to get you
20-40 meters? try to navigate on that.
Not to mention the tons of other problems such as access points moving and disappearing and the inharently weak signal makes wps less reliable under minor amounts of interference.
it's a neat trick for someone who has nothing better to do but with as advanced as gps is and the ability to track via cellphone I don't see this having any real market.
Dedicated Cthulhu Cultist since 4523 BC.
I can use this technology to find my keys because I use RFID keys to open my front door and start my car. RFID is more secure then most people think, because it can be used in combination with keying in a short security code. RFID can be used in combination with biometrics for an unpresidented level of security. For example, to open my front door my RFID keychain has to be within 10 feet of the door awhile I shit in a special box.
Stop invalid scientific research. Ask your local scientists to feed their lab rats with a phytoestrogen-free chow.
"I'm with stupid ^"
Most people don't even bother to name their networks. "Linksys" "default" "netgear" are what I typically see.
> one has to wonder how well it deals with people moving their wireless access points
This is especially true with ad-hoc networks.
I wish there were an open source DGPS project out there.
The premise seems simple enough: Have one GPS at a fixed position, and the other receives corrections via radio.
But I haven't been able to find anything.
My house sits on a large lot (over an acre) and I've wanted to survey it fairly accurately (within a foot at least) to recreate it digitally and be able to plan shops, gardens, landscaping, etc.
Lose Weight and Feel Great with Isagenix
20-40 ft? This is totally useless for street navigation, surveying, etc.
What this is useful for is grander scale positioning without the need for a GPS device built into a portable device.
For example, timezones are far larger than 20-40ft. Laptops could be configured to automatically adjust the timezone setting to match the closest access points, no GPS device needed. A weather monitor utility could always automatically show the local weather. A star map could be configured to show the local sky. I'm sure many people can think of others.
http://brandonbloom.name
Let's see. According to this ling http://www.linksys.com/products/wirelessstandards. asp WIFI range is 100-150 feet for an indoors AP. In other words... Given a map of San Francisco and a list of APs, I can get roughly 30-50 meter location accuracy as soon as I can spot an AP.
I failed to see the practicality of this.
First the resolution; 20 meters? The common GPS receivers have around 3 meters resolution. Which one do I prefer? Well GPS of course.
Number two on the list, range and availability. WiFi signals are everywhere in large cities, but once you move away a bit then it is gone. What is the point of having a positioning system that only work in the city center?
Then there is the convenience. It depends on a database of APs, but APs are not things that you can use as landmarks. The rate of changes is much too quick. With the GPS? It works globally without me worrying about anything. Which one would I choose?
Comment removed based on user account deletion
WAAS is not "stationary satellites". There is such a thing, called a pseudolite, but that's not WAAS.
The ground stations generate the corrections, but these are sent to stationary satellites in geosynchronous orbit. A WAAS capable GPS receiver can receive those signals in addition to the GPS signals with a compatible GPS receiver. This information is in the linked article.
It's actually pretty useless for car navigation systems, but good for marketing. Since SA was turned down, the WAAS signals only are correcting for atmospheric or small timing errors in the GPS signals. These errors are fairly small. In a car doing down a highway the error is very tiny when compared to the "error" you get when a vehicle has moved 25 meters in the time between position updates. Additionally, WAAS corrected positions do not correct for errors that are local to the moving receiver, that is relections or multipath errors seen by the receiver but not by the reference stations. Those errors can easily be an order of magnitude larger than the errors WAAS might have corrected.
So for walking around a field looking for a rubbermaid containter filled with chotchkes, it might be handy, but for car navigation it's just so marketing can list it as another feature.
That (In addition to the ability to receive GPS signals) is what E911 is.
The fact that cell towers are in fixed positions and broadcast with strict timing requirements is why E911 works even when signals from less than 3 GPS satellites are available - the towers themselves are essentially used as "pseudolites" in the position calculations.
retrorocket.o not found, launch anyway?
I remember using it hiking, and found it quite useful. I hope that this technology spreads to other devices!
Hi, I'm working with GPS tracking and have just finished one of the worlds largest online tracking of a sail reagatta using GPS/GPRS devices. (watski.watland.net). Earlier I have worked with various other systems for tracking, one of them using the distance from a GSM antenna as the measurement. Every base station(antenna) keeps a log of wich GSM phones are in the area and the strength of the signal, if you cross reference this with other base stations you get a pretty accurate measure of the position, but still there is a huge difference between this and GPS. It is pretty hard to get the accurancy lower than 50 meters (you probably wouldn't navigate your car after this...)
So, what I try to say, is after several years of working with various technologies, it is hard to match GPS on accuracy, then there is reliability and different service providers and so on...
I wonder how long after WiMax is released that the same type of method can be used. It could really be a better technology than GPS if done correctly. I really don't like waiting for my GPS handheld to determine where every satellite is and connect to each... Just my two dollars -P-
Are there any access point in the jungle? It will not be practicle for outdoor usage.
If you are a senior Java developer with GIS experience these guys may be interetsed in You http://www.skyhookwireless.com/company/careers.htm l
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Is that unique identifier such as SSID or access point MAC address (is that even accessible to a client)? Since a large number of people would check "Do not broadcast the SSID" following their manufacturer's manual on security, while the other would leave, as people before mentioned, some default setting.
Microsoft is using this technology in the coming Virtual Earth to automatically locate your position on the map.
Read about this technology in technical journal, not some info-regurgitating tabloid like C|Net!
This service is cool and all of that, but an accuracy of 20-40 meters???
Modern civilian GPS (been using the OmniStar HP service recently.. granted, its subscription-based) has a (real, tested, this-is-not-a-fucking ad) optimal-condition accuracy of 10cm. Even good old vanilla-plain non-SA GPS is at least 10m accurate (horiz position (lat/lon), 95% conf). Src: http://users.erols.com/dlwilson/gpsacc.htm
Anywayz, definitely don't forget GPS... yet?
WHOOSH... is that the sound of my sense of humo(u)r flying off? Blah.
why would anyone give away all the info and a ssn# (for tax reasons) on a web site that is new (to most)? hb.
As for the accuracy - I am sure it's ising a more sophisticated approach than GPS - they may not even take the signal strength into account (or just use it as a minor factor).
They probably do a match between the discovered set of APs (I guess you can get MAC addresses or something) and figure out the most likely point where you would see such a set. There some interesting math behind it and it probably has nothing to do with triangulation.
Besides, their client is probably constantly updating the database, so new APs are added to it.
better target their ICBMs at starbucks or not? Arash
Arash Partow's Philosophy: Be a person who knows what they don't know, and not a person who doesn't know.
From the article:
Morgan adds that GPS typically only locates things within a few hundred meters
Huh? I can get down to 6 meters and in AUS we don't have WAAS. This is just FUD.
And what happens if they move a wireless access point?
There are lots of applications that could do with indoors coverage, but this isn't a GPS killer.
I could see something like this being a complementary addition to a GPS. GPS+WPS or somethink like that. But the power of GPS is the ability to locate yourself anywhere on the planet that you can have line of site to enough sky. The WIFI coverage of the earth doesn't compare to the satelite coverage you get.
What I'd like to see is technology that could give position down to the centimeter (or at least down to the size of the unit). They you'd get some fantastic applications in the building industry for example.
These posts express my own personal views, not those of my employer
yes, 20-40m sounds really bad compared to GPS, but different applications need different accuracy. Imagine how many applications can do well with 1 mile accuracy location system, e.g. http://local.google.com/ uses your zip code and it works well. Currently our computers/laptops have almost no sense of location at all, and if Wi-Fi provides a cheap way to do location and enables cool applications, why not?a b.pdf
I co-authored a paper discussing various issues in such a WPS system. One of our conclusion is that AP moves/turnovers have slight impact on accuracy http://ramp.ucsd.edu/~ycheng/pubs/mobisys05placel
This is painted up and down with security concerns. Does it use any sort of security when contacting the servers? Maybe SSL?
What's more, how can it stop people from poisoning the well by deliberately sending out false SSID's or MAC addresses, or whatever it goes on to determine uniqueness?
Biggest problem, hands down, is that access points do move and change SSID's and even change MAC addresses (well, mine do when I tell them to). A more workable system would be to endow access points with GPS and let them inform the host of their locations. Some modicum of accuracy can be assumed this way and the signal strength and triangulation can still be used to determine the host's location. But this still has security concerns.
As a frequent wardriver i havhe noticed that considerable amount of acces points are with identical MAC. I reall dont know why this is, but this makes dependable position detection impossible.
1) The recent press release by Atmel and u-blox announcing indoor capable GPS http://www.u-blox.com/news/SuperCS.html
2) Better coverage area
3) Not reliant on the masses to provide APs and keep them in a consistent spot
4) GPS probably functions better in a blackout
5) Don't need a laptop (Not sure if WPS requires one)
And to finish off the list, I'm sure if you just scan the rest of the comments you will find 5 more.
Interesting idea, but it doesn't seem like a good bet when there is already a good solution out there.
I did a lot of research on this topic for my sensor networks class and we came to the conclusion that it would be highly inaccurate.
I feel sorry for the poor techs who had to drive around and write down the addresses of all those access points. Too bad they couldn't use that inaccurate GPS system to make it easier.
Pity for the guilty
is treason to the innocent.
On a more serious note, this sounds suspiciously like a project I worked on years ago, only this one is not as deep. Or nearly as accurate.
KoA
Alaska men should hit the trail for breasts
Now I think we can compile a WiFi hotspot map and lookup the nearest one rather than rely on those stupid faded chalk marks. If only they'd carry the SSID as well ..
:)
Btw, we've already been there and done positioning using local RF stuff.
I had this app that used a MIDP form to draw the way you moved. It used to go crazy when I was in the lift - but on the horizontal it used to work nicely. I couldn't release it because it uses a few undocumented Ericsson OPA APIs. It used to obtain timing advances of all nearby towers by forcing a network search. Triangulate and measure displacement. The more towers you have the better your placement will be - but this only measures displacement. It used to chug battery like anything - and my screen used to flicker everytime it hit network search (I think I must be sterile from using all those unshielded mobiles).
Sadly, I've lost the code and that job
Quidquid latine dictum sit, altum videtur
Put a GPS and a laptop in the boot of a taxi. It collects updates, and every time it finds an unprotected AP, it uploads the data to a central database. Client computers could do the same thing for downloading. Parasitic navigation! Wonder if this would be legal?
10 ?"Hello World" life was simple then
This was done decades ago in Aviation as LORAN. It used radio stations to pinpoint an aircraft's location. LORAN has been pretty much abondoned for - you guessed it - *GPS*.
something I'm wondering is, if it doesn't have the capability to uplink via satellite to receive the location information itself (i.e. it cannot pinpoint you through the same link its sending the database's location data), then does it actually have a global uplink like that or does it make use of open wifi hotspots?
I didn't visit the companies website but I read the article and that makes me wonder.
The client software running on the tracked device measures the signal strength of the access points, forwards the data to the server which calculates the position. The big-brother scenario is avoided as long as you still have to install the client yourself.
The major drawback of the system is that it needs extensive calibration, since they are using not only the available access points, but also the signal strength of these. Normally they suggest calibration in a 5x5m (15x15ft) grid. More calibration points yield a more accurate result.
And now the piece of information you have all been waiting for: accuracy. With a good calibration this can yield accuracies of arround 1m. In my tests (indoor) the accuracies fluctuate a bit, but is at least better than 3m 95% of the time.
Just as the system described in the original post, Ekahau requires no extra hardware (we already have 2-300 APs on campus).
I did my masters thesis on this a year ago. I used Java on an iPAQ 5555 (with a little bit of native C++ through JNI) and a Java server using a MySQL database.
Using 6 access points covering a fairly large building, I managed to get an accuracy of about 4-8 meters. The trick it seemed was how you filtered the raw signal strength data, a better (slower) filter gave better accuracy but much longer response times. The 4-8 meter accuracy with around 7 seconds response time proved the best tradeoff for my application.
I am not at home for the next few days, but if anybody is interested in recieving a copy of the thesis or the code for the system, please write a comment in my journal.
Freespirit
I've developed a quit similar algorithm while I was studying, 5 years ago. We used it here for Indoor navigation purposes (thus GPS won't work anyway) and we've been able to get accuracy down to 2-3 meters (using some kalman filtering and an environment model). Sadly I cannot provide an link to this works because they are all property of the company I work for (Fraunhofer IIS). :(
This makes no sense, WPS cant even be compared to GPS! Do you have Wi-Fi hotspots in remote Amazon forests?
"A mind is a terrible thing to waste
Please notice the G in GPS ! The system is global and really works everywhere outside the buildings. And "everywhere" actually means outside your city and even outside USA!
Can u imagine?!
Since a large number of people would check "Do not broadcast the SSID" following their manufacturer's manual on security,
What manual says to do this? Turning off SSID broadcast is *not* a security measure in any sense, at all.
For one thing, the SSID is included in every single packet that the access point sends out. Period. So getting it is easy with or without the SSID broadcast.
For another thing, turning off SSID doesn't prevent anybody from connecting to the network. It will prevent stupider displays like Windows's wireless page from showing that access point as available, assuming no other AP has the same SSID being broadcast, but if they select that SSID from another AP or if they put it in manually, then they'll connect to your network just fine.
If you want security, enable WPA. Turning off SSID, filtering by MAC address, these are not security related adjustments, and add precisely nothing to your overall security strategy. They might be a way to keep your idiot neighbor from connecting to your network by accident, but they won't keep anybody from connecting to your network on purpose.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
How would one get lost in a dense city? Street signs are everywhere and dense fog won't make orienting much more difficult. There are always people whom you can ask. GPS is useful in areas without population: open sea, deserts, Lappland, Alaska. The use case for such a device is pretty much zero.
Yeah, GSM CellID is a great way for getting a quick-and-dirty position. Since most people always have their phones with them, some kewk stuff can be done:
http://www.zone-mr.net/?act=CellTrack
The downside is that accuracy sucks. Even the 50m you gave is wishful thinking, and probably assumes a city with a high density of cells, and nice linear relation between signal strength and distance.
The US is getting more and more paranoid. I wouldn't be surprised if it is routinely shutdown every time we are in a homeland security declared red alert.
Nice to have a alternative.
Also, most new laptops have WiFi these days - not GPS.
That alone make this useful.
Right now this "technology" may not seem so useful, but I can see the possibility of it being more ubiquitous in the future. GPS can't locate anything when line of sight is blocked. This WPS would alleviate that. Improve the position accuracy, global coverage, and this may be quite usable.
although it may sound just as useless as he parent I think there could be some merit to helping the non experianced vacation scuba diver find his way back to where the boat is. If the Open Water movie has tought us anything let it be that (A) we should have waited for the dvd release and not saw it in the theater. and (B) it sucks to come to the surface only to find that the boat is not there. At the very least the UNS (Underwater Navigation System) could have at least made them surface where the boat was supposed to be. That would have made for less arguing before they were rescued by the Dolph.... I mean sharks.
This service is interesting, but not very useful. How often are you using a wireless connection but you dont know where you are?
It reminds me of a project a friend of mine was working on earlier in the year. The college of computer science here at my university in Boston has a brand-spanking new building with cisco wireless routers built in (through all 15 or so floors). My friend was working on using these routers to triangulate the position of all of the wireless users.
This was accomplished by maticulously mapping the average signal strength of each router at various distances (1 foot, 2 feet, etc...). Since all the routers overlap a bit (as they should), extrapolating the position is not that hard. You just need a minimum of 3 routers to see any user. The more routers seeing the user, the more accurate the location. Its strikingly similiar to how the epicenter of an earthquakes is determined.
The authentication server behind the wireless network could then deny access to connections outside the building. The aim was to stop leechers from the nearby dorms and apartments, while still providing free authentication-less access (http only without authenticating) to the inside of the building.
Anyway I need to check up and see how that project is going. It was progressing well last time I checked. I think network security is a far better application for WPS.
There are 10 types of people in the world. Those who understand binary and those who do not.
I just moved my linksys router to the other side of the house. Neener, neener, neener!
The nice thing about GPS is it works ina very large area of the world, and even better the more remote you are, which is the inverse of the WPS analogy.
GPS doesn't handshake or anything, it is like a radio device (literally) interpretting signals.
GPS(n) with some kind of third party WAAS type configuration can pinpoint you to a meter.
GPS swarming is a way of GPS devices helping each other out over GSM networks, when one/two in the swarm drop a satellite signal.
I think it is a fairly good solution for localised services, if you have a map, turn on your PDA, list networks, and you will see:
Marios Pizza WiFi
StarBucks Wifi
XYZ Wifi
With a little more info, wifi boxes themselves could help you find them, and the wifi could be a geobeacon for local services.
(or use a GPS style geotag)
#hostfile 0.0.0.0 primidi.com 0.0.0.0 www.primidi.com 0.0.0.0 radio.weblogs.com
So how does it factor in if I use a tool like FakeAP or something else to generate 50,000 fake access points in a city?
News Reporters Make Tasty Polar Bear Treats!
I'm assuming this is being done for profit, so when can I expect my first check? After all if my access point is being used for something like this then I expect to be paid for it. As I'm sure many other people will also want to be paid for allowing their access points be used for a project by a private enterprise who will be charging money for using their service.
Carnegie Mellon already did this, but our engineers don't talk to our business majors...
http://cmusky.net.cmu.edu/about.html
Wouldn't mesh routing and signal strength analysis at least help to keep the positioning data more accurate?
Just a thought...
I don't know the meaning of the word 'don't' - J
Hi, guys, remember me? 'Course you do! Funny to see you guys lambasted in a public forum. Thanks for the lesson!
Zhrodague.net - I do projects and stuff too.
Even though WIFI is a broadcast network, even when it is secured, it is a signal from a private device. For these people to use my access point beacon to provide their subscriber with any kind of service is criminal tresspass and can be prosecuted as such. Remeber, I own it and I pay to power it.
Of course, if they want to work out a compensation agreement either fee and/or free service, then I bet we can grant permission to use...
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
Can't you triangulate from FM radio station signal strength?
It woud have the following advangates:
Way smaller database
Way more coverage
It should be easy to do with the adevnt of software radio.
The only down side, is that you wouldn't need this company anymore!
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
Can't wait to have this system in France. We would love it!
No thanks! I'll keep my Differential GPS that gets me to within 8 feet.
Best Buy can have you arrested
What happens when an AP or a bunch of AP's move? Maybe a large company upgrades to an office across town, or the local Starbucks shuts down and relocates to the east side.
Wouldn't that screw up the positioning?
"Forget GPS" my ass... i certainly HOPE they don't speak of this as a replacement for GPS.. but definitely a cheap, and compatible way for PDAs and Laptops to obtain GPS-type information.. I could see it now.. WPS networks getting hacked and you end up having people driving their cars in the ocean because thats where it said to go..
*plays the Apogee theme song music*
"Morgan adds that GPS typically only locates things within a few hundred meters" Trhat's not true. A typical handheld GPS that sells for under $200 will tell you your location to within about 6 to 10 meters. The wi-fi system if it can only give you 20 to 40 meters is not as good. But wi-fi does have a large advantage in that you may already own a reciever so rather then costing "less then $200" it is truely free, as long as yo are inside the mapped area.
but do you really trust that this current fear mongering Bush administration won't screw with SA somehow?
I'm in Mountain View, CA. My usually very reliable Garmin eTrex was giving *wildly* inaccurate readings, putting me nearly 1/4 mile off and saying that I was at 2,400 feet. The GPS said that it had excellent signal strength from no less than 5 satellites, yet it was completely off.
Defective unit? No. I took the same unit camping the following weekend and it was accurate down to 5 feet.
Maybe the fact that Moffett Field/Onizuka AFB/NASA Ames Research Center is close by?
Since the military can (and has) jammed GPS in a limited area, how are we to know whether or not it's happening to us *right now?*
I suppose we could wait months for a FOIA request to come back, but otherwise.. we wouldn't know.
When I lived in Yokohama, the prefectures would all have very detailed map books, literally listing the name of the house resident. (We were renting a house, and our family name was right there in the book on the right house.. I was able to find all of my friends there on the maps too)
;)
Japan does a great job at mapping their urban areas. Although, Dominos Pizza was always late delivering my pizzas because the maps didn't account for a large apartment building blocking any view of my house or the tiny ass alleyway (driveway, if you even want to call it that) leading to it.
They used WAPs to triangluate position. How interesting.
What would happen if you and your neighbors decided you didn't want your radio signals being piggybacked by these folks? You could do fun things like install directional antennas and rotate on a regular basis, or line the walls of your house with grounded copper grid.
Or you could change the ID of your WAP. Or not broadcast it at all. Why particiapte in their little moneymaking scheme.
Since I regularly pick up stations from a large part of the world on the 20 meter wavelength band on my ham radio, I don't think it is too useful for position information. However, a statistical analysis of the proportion of callsigns I hear leads me to believe I am somewhere in the western half of the continental United States. Could someone please give me directions to the nearest gas station?
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But yeah, people should learn that "rouge" is French for red, and "rogue" is English for unexpected/abnormal/destructive.
And while we're at it:
No-one with a basic education should mix up their homonyms. They're wrong if they think nobody notices. Mistakes here, there and everwhere make the post lose credibility. Check your posts before posting or you're going to be ignored.
Well let me flesh that out before the corrections come in.
FCC has jurisdiction in DC and territores. They also have jurisduction in matters of interstate signals for commerce.
Read Title 47 of the statutes.
See: here and
here
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
A twisty little maze of APs, all alike?
I think the original poster was slightly conflating WAAS and DGPS. Yes, WAAS is based on data from a network of land stations that is compiled and then relayed via geostationary sats. DGPS is a different system that uses a local low or medium frequency (?) station to transmit a correction signal, and supposedly isn't quite as accurate.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Wonder how many private homes with unsecured wi-fi nets will be picked up in this dragnet. Now here is a subscription service for every slimy data thief with a laptop and a bicycle to find innocent victims to target. But then again why steal it. Say a bookie has some hot data that he does'nt want a rival mob boss to have. Why he stashes it on YOUR home computer and rides on. Next day he comes back when it's all clear and gets it back. You probably never know the difference 'cuz he will hide it under a long trail of 'hidden' attribute directories with inscrutable names in your lovely windows system that you bought from whereever and left in its default suckerbait settings. But you the common dumb windows user don't know, because most windows users know little more about their machines than to turn them on and stick in the next game disk or click the browser button on the bottom for their daily ration of spyware, cookies, directX controls, remote admin programs...etc. The bad part comes when the mob guys catch up to our bookie and lean on him hard for where he stashed the data. That's when they break down that innocent user's door and beat the hell out of him. Nobody believes anyone is innocent in this world any more, so the wiseguys will think this poor Joe or Mary Lunchmeat is part of the bum's action.