High-Speed Wireless LANs Move Forward 115
GrokSoup writes: "Neat article from the WSJ (free site) about European hackers using 802.11 technology to create limited-range, high-speed outdoor networks. As you might expect, people are messing with directed antennas to send signals up to a kilometer. While I've tried this to get from the house to the pool, the idea of banding together in open-source fashion had never really occurred to me. Nifty!" We've mentioned consume.net before, but this piece mentions some interesting possibilities, like how the same idea may result in an approved-by-the-Man wireless network in Sweden, and the golden hope that multiple connection methods will let us switch handily among several wireless protocols as the occasion merits.
wireless wan in australia (Score:1)
excellent (Score:1)
mov ax, 13h
int 10h
I want a wireless decentralized Internet (Score:2)
Re:excellent (Score:1)
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In just a few months.... (Score:1)
Who pays for the wireless-to-wired part? (Score:2)
I have a always-on connection, but my ISP would crucify me on the telephone pole outside my house if I started routing random wireless user's packets through their network.
For an experimental setup, there are plenty of universities and the like willing to donate bandwidth. I don't see this scaling, though.
Eavesdropping (Score:2)
The case I remember was where some computer-magazine was testing wlans and they saw the entire domains of the hospital (or some other medical facility) on the other side of the street..
I'm staying aways from these things...
Plus I think there's enough waves going thru my head already..
Re:Who pays for the wireless-to-wired part? (Score:1)
That is right on par with high-school-dropout-sysadminning-for-pot-money comment I read earlier to-day. Thank you, good sir, for your most enter-taining witicisms. Right-O.
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London? (Score:1)
Re:In just a few months.... (Score:1)
Re:In just a few months.... (Score:1)
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Re:Eavesdropping (Score:2)
Finland has wavelan ISP's (Score:5)
In practice you need a line of sight and radio frequency is used by many other devices. A common joke is to call it instead of a "wireless Network" a "connectionless network". Still those few who have managed to get a subscription seem to be more than happy.
Re:London? (Score:1)
Re:Who pays for the wireless-to-wired part? (Score:2)
Uh Oh (Score:3)
Julian Priest is walking east down Clink Street away from his office. He's holding his laptop in both hands and surfing the Web as he goes through an enviable five-megabits-per-second link to his desktop computer.
I can see the headlines....
LONDON - Chalk two more victims for Clink Street. In a continuing display of brutal idiocy, two men were killed earlier today when they inadvertently stumbled onto the busy thoroughfare. Ralph Foster, of York, was "surfing the web" on his new laptop while out for his lunch time stroll. Witness say he had just logged on to Hotmail.com and was happily deleting spam when he tripped near the curb and tumbled out headfirst into traffic. Police say he was killed almost instantly - managing, however, to log out before logging off.
Simon Edwin, of Chester, had a slightly different fate. With two Palm V's in each hand, Simon was actually playing a modified version of pong online - against himself! The police cannot confirm his exact cause of death, saying only that they have yet to find the 2nd PalmPilot.
These unfortunate events come just days after the loss of the entire development team from WebSolutions.com, who met untimely deaths when their Internet-connected coach flipped four times after the driver veered to avoid packet loss...
Die capitalist peegs! (Score:1)
the alternative is to setup programmable "antennaebots" that are on a predtermined schedule to re aim the antennae(s) from one computer to the next either in a cycle or to send a "yoo hoo over here" signal through narrowband dialup to tell the other computer you need to connect.
I had considered this as a possible way to share mp3s that might be better than napster/gnutella in highly populated and geographically flat areas.
Problem: part of the routing data would probably need to include geographical location making it EASIER to track you to your location. one answer may be crypto/steganography, but even then for it to work people would need to be able to identify files on your computer.
even with the potential privacy snags the prospects of a network who's infrastructure is owned by the public not by megalithic corporations.
only with a completely unownable system available can we hold on to what freedom we have on the currently propriatary network infrastructure.
Need more security... (Score:1)
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Re:Eavesdropping (Score:1)
Yeah, bad planning for placement of the base station, but I'm betting that they put the telco closet by the elevators for easy access to wiring all the floors together.
-Nev
1km?? (Score:3)
Currently we have a 802.11 based system which can do up to 30km on a p-t-p link and 5 km in radius!!
We're using a selfmade module for enhancing the signal on the receivers end and 1,8m parabol antennas.
;jjjjj;;;;;;;j;fsf;;;orking ve;y well! (Score:3)
Re:wireless wan in australia (Score:1)
Daisy Chaining... (Score:2)
My guess is that the easiest way would be to build in some sort of GPS ability (so you know where you are in relation to your nearest land-node). Your packets hop from wireless node to wireless node until they hit the land-node. Same technique for receiving packets.
Re:Eavesdropping (Score:3)
Nobody thinks about abuse of the system... (Score:1)
Seattlewireless.net (Score:3)
Re:Eavesdropping WLANS (Score:1)
i gotta agree with these guys. what your saying is just scaremongering. at the moment i am working on a wireless lan project and i know that the hardware offers 128b encryption.
i *think* the story you are talking about is some "techN0 journalist" drove past Apple HQ with an iMac and a Airport connection, and "sniffed" the insecure net inside Apple.
As the guy previous said, if you are scared use a VPN.
Would you put a Windows box as a server?
rgrds
b-B-t
Re:Seattlewireless.net (Score:1)
Oh well, it should be funny to see how badly their site gets jacked up. I hope they made a backup.
Directory needed (Score:1)
Limited (air) bandwith hurts (Score:2)
With a wired Ethernet, if the load gets too heavy we just split the subnet. With my DSL line, if my neighbor gets DSL I don't suffer. But I really don't want my neighbors to get 802.11 installations, because then my performance will drop -- both in-home and (once the rooftop arrives and I drop DSL) to the Internet in general.
This a fundamental problem with wireless. Highly directional antennas help, but it's expensive to narrow the beam to 1 house from a km away, and so our current installation has an omnidirectional antenna at the base.
Re:Seattlewireless.net (Score:1)
Re:Limited (air) bandwith hurts (Score:1)
Wireless LAN as a service to customers today? (Score:1)
We have (Score:1)
http://www.iinet.net.au/products/broadband/city
expensive though.
What are the implications of this for wap ? (Score:1)
Ethernet started wireless (Score:2)
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Re:What are the implications of this for wap ? (Score:1)
Re:Need more security... (Score:1)
Re:Wireless LAN as a service to customers today? (Score:1)
Line-Of-Sight lookup? (Score:1)
Re:Eavesdropping (Score:1)
And oh yeah, you can encrypt this stuff.
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Low Cost Wireless How-To (Score:2)
Re:Daisy Chaining... (Score:1)
Of course, packet radio is only 9600 bps
Wouldn't it be cool if you could do this with broadband wireless though?
Re:Line-Of-Sight lookup? (Score:1)
Re:What are the implications of this for wap ? (Score:1)
Besides, in Holland we have two networks: 900mhz and 1800mhz. Since 1800 isn't much less from 2400 I don't think it would make a difference.
Mark [zwienenberg.com]
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
Re:1km?? (Score:1)
If so, pls post a link to technical docs
nicholas
http://squat.net/ascii [squat.net]
Re:Directory needed (Score:1)
Re:What are the implications of this for wap ? (Score:1)
L0pht have been trying to do this for years.. (Score:1)
Not sure how far they've got, but the've got lots of technical info for anyone really interested.
Re:Directory needed (Score:1)
Re:1km?? (Score:2)
But you can find further information under http://www.funklantechnik.de (in german).
SSH (Score:2)
Re:Need more security... (Score:1)
As opposed to winning a tape drive that isn't free? Why would I want to do that? Surely I can just
Someone explain to me.. (Score:1)
802.11 in Environmental Research Re:Daisy Chaining (Score:1)
More information about this can be found here http://www.botany.hawaii.edu/pods/ [hawaii.edu].
Hacking the 802.11 protocol for peer-to-peer passing of packets is very useful in this situation because this alleviates the need for extremely powerful antennae to be setup and pointed to many sensor stations scattered across a forest. Instead the pods are all within reach of another and packets are passed back towards the home station. Nifty.
Check out the pictures of these pods on the site. Each station is custom made to blend in to the surroundings, looking like a dead log, or a lava rock or something.
Re:Who pays for the wireless-to-wired part? (Score:2)
The nodes which have a wired connection to the Internet should advertise a default route with a suitably low metric - as these routes float through the RIP network, the one that 'wins' at any node is the route that represents the fewest hops to the wired Internet connection.
There are probably much slicker ways of doing this but they'd also be more complex to set up.
Probably all the wired-to-wireless gateways will need to do NAT. They should also do IPSec for those nodes that don't have WEP type encryption.
Re:802.11 in Environmental Research Re:Daisy Chain (Score:1)
Some kids living near these areas in Hawaii are in remote areas without high speed internet connections. (Almost the rest of the Hawaiian state has both cable modem and DSL available.) This network may also allow those students to finally have high speed Internet access.
Re:Need more security... (Score:2)
I do the same.. (Score:1)
I happen to work at an ISP, which does exactly the same (InWay [inway.cz]), i.e. building a wireless network from BreezeNet's with external antennas, which were designed for office-wide wireless LAN originally..
It's pretty common alternative to expensive land leased lines from monopolistic Telcos here in Eastern Europe, these ISPs have 1000s of customers.
BTW, it's not very wise to build such a network based on DSS (direct spread spectrum) devices (like WaveLan) where FHSS (frequency hopping spread spectrum) devices are also allowed in the same band -- FHSS always wins the interference duel with DSS, because DSS sends the same data still at the same frequency, while FHSS hops over all the band randomly.
There's also a very cheap (some $250 for both ends) device from Siemens called Gigaset M-1000 Data or something like that. It's a serial port version of a wireless phone It just extends a serial port (V.24, 115200 bps) over cca 500m distance, with external antennas maybe even more.
Good for broadband access... (Score:1)
And yes - it's 802.11b.
And yes - we are all operating at different subnets.
And yes - I will have a Linux firewall to protect my LAN at home.
This reminds me... (Score:1)
Now, instead of explaining why I had to get a second line to someone: "Well, I'm running a BBS." (other person) "What's that? Is that something like AA?"... Now I get to explain an antenna: (o.p.) "Why do you have that big thing on your roof? Is that a Satalite?" (me) "No, it's for the community based underground LAN." (o.p.) "If it's underground, why the antenna on your roof? What's a LAN anyway, is that like a satalite TV?"
Oh well, some things seem to change but essentially stay the same.
I wish this would get popular in US (Score:2)
Clearing House (Score:2)
Would anyone from Windsor, Ontario, Canada be interested in building such a network?
Re:Eavesdropping (Score:1)
Re:Eavesdropping (Score:1)
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Radiolan in Älvsbyn aswell (Score:1)
At the present, I am satisfied with it, but time will show whether the latency will increase drastically with the number of users.
However, it is still the most cost-effective way to connect all the stand-alone houses to the internet with some amount of speed.
Considering that the available alternatives still are ISDN and modem, the radio-lan is a very nice solution. The only backside to it seems to be the cost of the hardware.
B.t.w... is the 802.11b cards able to speak with other 802.11b cards from other manufacturers?
Lucent/Nokia/Symbol/etc...
Re:Who pays for the wireless-to-wired part? (Score:1)
That reminds me of a part in A Case of Need by Micheal Crichton where one character is describing another (ill-tempered) character. He says something along the lines of... "I hear that he carries around a bag of nails and a hammer in case he ever gets the chance to crucify someone"
Re:Clearing House (Score:1)
Re:Radiolan in Älvsbyn aswell (Score:2)
Re:excellent (Score:2)
So? I've done it here for months (Score:1)
Re:London? (Score:1)
You really need to check out consume.net [consume.net]
haven't we seen this before? (Score:1)
Re:Clearing House (Score:1)
Eavesdropping 802.11b is child's play (Score:3)
There is 64/128 bit crypto, in each case 24 bits are taken for the node address, leaving 40/104 bits for encryption keys.
Crypto is done using RC4, a system with known, exploitable weaknesses.
No Wires Needed [nwn.com] offers cards with factory-installed public key encryption and Diffie-Hellman support, but they do not offer their cars in the USA.
Good overview in Network Magazine (11/6/2000) (Score:3)
Available at http://www.networkmagazi ne. com/article/NMG20001106S0004 [networkmagazine.com].
Transmission power regulations? (Score:1)
The maximum power level is counted as equivalent of an ideal isotropic antenna, so if you transmit at say, 4 dBm, and add a 24 dBm antenna you are at 4+24 dBm, exceeding the maximum by almost 50% ! With 1.8m parabolle, you could be well over few Watts.
Big deal. (Score:2)
Many people, for several years, have been using wireless LAN cards and doing links of up to 15 kilometers. Several companies even originally based their wireless bridge products on wireless lan cards + some kind of RTOS on a small board.
I have 802.11 links working over 15Km........ it's *easy*. This is barely even a hack these days, and it's nothing new. I mean, oh my god! You put a different antennae on it, and the radiation pattern turns directional, increasing range! WOW! It's not like every hammie in the WORLD doesn't already know that...
That's incorrect. (Score:2)
Encryption is the key, though..
*OLD* wlans people, had no other layering to provide security. New stuf most DEFINATLEY does.
Why do you assume it's IP? (Score:2)
Who said anything about IP? Many things in windows networkign are discovered by *broadcast*, and use *other* protocols... like ipx or netbeui.
And by 'log-on' he probably meant he could simply see all their public shares; lots of older networks, especially windows ones, did not use any kind of client authentication.
Re:1km?? (Score:1)
I dunno about that. (Score:2)
I can say from experience, these are *just fine* for gaming. I don't know where you get your 'the latency is high' figures... but if the appropriate radio mac layer is used, latency is basically no different than a wired network of equivalent throughput. Why would it be slower?
The *tend* to be slightly higher in latency (measurable, but not noticeable), due to overhead in dealing with the rf medium.
Get real. (Score:2)
You have to a) obey regulatoroy radiation requirements (dictates power and shape of radiation pattern allowed) and b) use the appropriate antennae.
For instance: the yagi's we use to do some 10km links radiate a 30 degree wide pattern. This covers *quite a bit* of ground at 10km That means, yes, that a bunch of end users can share a single radio channel, and you only need one antennae each.
This problem is fundamentally no different than cellular problems: it's all about frequency re-use. You use alternating polarizations, proper channel separation, and can quickly built a tower that has, say, yagis every 15 degrees around the outside, covering an entire circle, giving you some nice coverage.
Privacy snages? The Internet is alreayd a public medium.. you can't control your packets once they leave your network.
wireless network cards almost all have built in encryption now.
Routing data does *not* need to hold your geographic location; it's very similar to ethernet.
Regulations? (Score:2)
Do you know whether or not this violates the regulations?
I know that we have easily done large links like this before, but never within the bounds of the regulations on the ISM bands... I'm sure Germany follows such regulations as well..
Re:Ethernet started wireless (Score:2)
You can't do collision detection, and you can't do carrier sense. Only one central node is guaranteed to see everybody. So they have a system of requesting a slot, etc...
Wireless Internet Access. (Score:1)
If you get this post, it worked again.
Correction (Score:2)
I think the answer has more to do with power levels confusing the dsss receivers.
You are right about which one wins the war though...
Check if this is legal in your Country First (Score:2)
The idea of adding a directive antenna to a system to get most gain and thus a longer transmit distance is sound. The problem is that you can also interfer with anyone else system who happens to fall along the axis of the directive antenna. This is why most countries regulate these systems on their EIRP, or effective radiated power and not their actual power. The difference between EIRP and power is that EIRP inlcudes the effect of the gain of the antenna. Thus if you use a more directive antenna than the manufacturer installed, you are almost certain to be illegal.
D.
Bay Area wireless projects (Score:2)
Shamelessly lifted from BAWUG [bawug.org]'s links [playanet.org] page, where there is lots of information about wireless hardware and software:
Re:What are the implications of this for wap ? (Score:1)
Re:Transmission power regulations? (Score:1)
Re:Limited (air) bandwith hurts (Score:1)
in the speed. Besides you need no licence for any bandwidth as long as its directional, for which 900Mhz + is. You will have to have a hub somewhere, where the writeless turns into internet.
Re:Limited (air) bandwith hurts (Score:1)
Possibly you're on channel 1 and your neighbor is on channel 2? That right there would explain it - the channels overlap. Move yours to channel 10 (the more seperation the better but anything over 3 should work.) Note: this only applies if using a point-to-point connection or if there are several unrelated access-points available. (The frequency overlap is designed to allow for "roaming". Not used it your situation.)
Do both you and your neighbor connect to the same access-point? If so that would also explain it. Remember this is a shared 11Mb (ok, really about 4-6) connection. Kind of like a cable modem - other people using it will slow you down.
One thing about access points is that everyone is supposed to be able to "see" each other - just like ethernet. If two clients connect to the same access point but can't see each other then they might both try to talk to the access point at the same time - not going to work. The solution here it to put your access point into a special mode ("ad-hoc" or something that sounds like that.) When in this mode, the access point will boroadcast a message telling all nodes to be quiet so the one node can send the message without being interupted. If this isn't done everything will appear to work great - even if under heavy load from one node. But under a heavy load from several nodes it will come grinding to a halt. A very hard problem to troubleshoot!!
Now if this doesn't describe your situation then there are things you can do to solve the problem. For example, try rotating the polarity of both antennas (transmit/receive). This shoud issolate your system from the other allowing both to work, even if using the same frequency.
Much of this depends on who designed and setup the wireless network. If they're new to it they'll have made some mistakes (speaking from experience.) Most techs thinks it's sooo easy to setup and use but neglect to consider some small, but important points. It's kind of like a web server. While it's not that hard to install Linux + Apache, it takes a little more to configure it as a production web server - just like there is more to setting up a wireless network then plugging in an access point.
I'm going to cut this message short but rest assured, there are plenty of other ways to potentially solve your problem. If you give a more detailed description I might even be able to help out. My last employer really allowed me to really push the limits of 802.11. Now doesn't a 55km link to a mountain top sound like a cool project? Hmm, I liked that job.
Willy
Re:Eavesdropping (Score:2)
When a wireless network is properly planned, there are 3, sometimes 4 or 5 layers of network security:
1. In freqency hopping systems, there are 78 hopping patterns. Only one will "sniff" the packets in the correct order.
2. ESSID. This is the network security password. Access Points will only respond to radios with correct ESSIDs.
3. WEP. Wireless Equivelency Protocol. This is 40, 56 or 128 bit encryption that encrypts all communication on the radio.
4. Direct AP connection to router/firewall. This stops any extraneous traffic from flowing over the WLAN.
5. VPN Encryption. Many ISPs are using VPN from customer premise gear to the router, which makes sniffing wireless more difficult than wireline, since there are 4 extra layers of security.
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No security will ever be perfect, but then again, most people using wireless lans are using them for internet access which is inherently PUBLIC anyways.
Re:Nobody thinks about abuse of the system... (Score:1)
It is possible to plan a network to maximize bandwidth to the customer without getting into cable-modem style problems.
Look at the cellular carriers - they usually have less than 10MHz of bandwidth in any given area, but use time division and code division to make sure every phone has enough bandwidth for the call..... they aren't perfect, but their call drop rate is less than 1/1000 on average now.
Re:Daisy Chaining... (Score:1)
Up in northern Canada, this was the _only_ way to connect some of the schools. Modems wouldn't work in several places due to the fact TELUS still uses some radio links. Hell, my parents can't get anything over 300baud on their 28.8 modem.
I should also mention that with the right amp and antenna, a 55km link is very reliable - even in a snow storm.
Willy
Re:Eavesdropping (Score:3)
To join the network you have to be a registered device on that network.
To eavesdrop you have to break the encryption key.
The alternative to wireless was to implement a fibre link, but it seems to me that it would be easier for someone to dig into the ground and plant a device on the fibre much easier than attempting to break the encryption keys on a wireless link.
Note this:
With our wireless link there are a fair few checksum errors on packets, resulting in the odd retry request from the other node. I presume that these errors would not be known unless you knew the encryption keys, making it almost impossible to crack the keys as you cannot tell where the errors are without first knowing the keys. Has anyone done any research in random (deliberate) corruption to encrypted traffic in order to prevent key-cracking? Obviously this would come at a performance cost (extra re-transmit packets), but I guess this is to be expected for higher security.
I'm sure anyone with enough spare time could probably break the keys, but probably not before we changed them.
Re:Eavesdropping (Score:3)
To obtain a lease from the DHCP servers you have to be a registered [cmu.edu] device on the network.
This approach seems to work well enough along with secured client applications (AFS, IMAP, etc via Kerberos [kclient]).
Re:1km?? - try 25+ miles (Score:2)
We are a coop for a reason - it was clear from the beginning that you can only build out *ONE* of these wireless networks in a region. We allow equal access to our network by all regional ISP's that want to particpate for a $3K startup (includes radio/routers which are coop owned/managed) and $300/mo. In short, a turnkey service far less costly than the 2 man years and $25K it would take to rebuild the nework form scratch. Coop members pay $60/mo for service - about the same as DSL and Cable service in this area - and lot's cheaper than ISDN. We are not a free open source like entitiy
Making it work more than a few miles without a 2500ft tower (aka mountain) is very difficult. Signal (wave front) diffraction is driven by pure physics
So flat landers with lots of buildings and trees, and no serious height, pretty much will have to live with short connections (under a mile or so), probably much less in typical city environments. This is much less a problem at 900mhz, is difficult at 2.4GHz, and a total killer at 5.7Ghz.
While some vendors say that 2.4GHz isn't affected by weather, that is only partially true, and only for links that have 15-25dB or more of link margin. Many of our 2.4GHz links have less than 10dB of link margin, and see slight rain fade, but serious signal loss due to snow which causes serious diffraction problems coupled with broadband noise refection problems at the repeater sites (noise floor goes way up during snow storms). We manage this by dropping the modulation rate to 5.5mbps (doubles the power per bit) and decreasing the packet size (enabling fragmentation) to significantly reduce the probability of CRC errors due to noise functions. At 5.7GHz rain drops just completely eat the signal, and rain fade is really rain-block.
Network performance with Hidden node operation, while managed by 802.11b, degrades rapidly underload. Aironet made a huge mistake when they failed to implement the Point Coordination Function called for in the 802.11 spec (PCF). In theory PCF can be used to stabilize the load curve, minimize load induced failures/overruns, which are a fact of life with hidden node architectures when using 802.11 devices in a wide area network.
There is a lot of RF magic in making 2.4GHz 802.11 wide area networks work - the stuff is worse than plug-and-pray. It pretty much takes a $2-20K spectrum analyzer investment to debug problems. Even with that expect side by side experiments to have radically different results.
Watchout for mixing FHSS and DSSS systems in the same area
Or operation isn't perfect
Network Magazine (Score:2)