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Secure Wireless Through Infrared Antennas
oogamrm writes "Everyone knows the main problem with Wi-Fi: Security. It's relatively easy for intruders to sniff packets out of the air and even connect to the wireless net. While most wireless companies have responded by trying to beef up the encryption, the University of Warwick's engineering department has developed an optical antenna that operates in the infrared band. This means almost no energy leaking through walls, and simple filters to block it from exiting through windows. The antennas can be so well tuned that several networks can be co-located in the same physical space. The whole story is available at news.com.com."
So, yes, it may indeed be more secure, but is the enormous leap backward in available bandwidth really worth it? I for one would much rather use stronger encryption than weaker signals.
Hey, anyone remember the IR wireless that JVC had years ago. I actually have one at my company that works, it's range is rather limited, but it's nothing that new. http://www.jvc-victor.co.jp/english/pro/lan-e/
This article is very vague about what exactly has been developed. I'm curious to know more, perhaps when it's unveiled at comdex.
They refer to it as an optical antenna. That is probably a misnomer. It sounds like what they have actually developed is a new type of optical sensor, perhaps with some special lensing. Lenses are much like antennas for light.
Current technology uses phototransistors which are pretty good at what they do. But they have a fairly wide bandwidth, that is they respond to a wide range of wavelengths. The article claims that their new sensor has a very narrow bandwidth. To limit the wavelength response of a phototransistor, filters must be used which reduces the signal strength.
They also claim that the device is 100 times more sensitive than current technology. A new type of filter which was very low loss could increase the effective sensitivity of a filtered phototransistor, so I wonder if this is what they have really developed.
Either way light travels in straight lines and I doubt if they're counting on cloud reflection or something, so this device would require a line of sight. That said, try aiming your remote control at a window sometime and see how the light bounces off and then to your TV. A device 100 times more sensitive may be able to take advantage of reflected paths that are currently unuseable.
Current outdoor point to point IR links using laser technology can be reliable up to several miles, even in rain. The units I've seen are over speced, so that without weather they are actually capable of working over much longer distances, but they aren't market as such.
-73, de n1ywb
www.n1ywb.com
It's funny that you mention that. I remember trying to transfer files at school from an IrDA capable laptop to an IrDA capable printer. It took 3 hours and in the end we had to build a cardboard tunnel to cut the interfereance out. (the funniest part was at about hour 2 when we realised that the manufacturer's plastic protecting sticky tape was still on the electronic eye of the printer. We peeled it off and got a much better signal)
Anyway, from the picture of the optical antenna, I would guess that it would be oriented upwards so that it looks like a big fisheye lense pointing at the ceiling. Since IR bounces off walls (I know because I've sometimes changed the channel on my TV while pointing my remote in the opposite direction) then I guess that the whole point of the optical antenna is that it is able to see the ceiling and not be blocked because if the direct LOS is blocked, than this omnidirectional antenna should get usable signal from the reflections coming in the opposite direction.
I was a member of the 802.11 comittee and sat on the IR PHY as well as the MAC subcomittee. The IR PHY was actually the first to get passed into the draft, ahead of the radio guys.
At the time, we approved a 1 and 2Mbps phy, and I was aware of other companies/universities working on 4, 10 and 16Mbps higher rate IR PHY. The company I was at, Photonics (now gone) was working on a 10Mbps product. IBM and Photonics both had 1Mbps IR LAN product in the market at that time (roughly 1994 or so).
OK - so we have had several stories in the past several weeks talking about WiFi this and that - and I have posted a few comments asking about wifi security. I would like some help from you guys - as it seems that there are several out there who really understand securing wifi networks. (I have written to both the sputnik (linuxcare) guys - and the locustworld.com guys - but have gotten no responses from either about security)
OOK - here is the scenario:
Imagine an ISP that is *only* wireless. They want to be a "community" ISP, want to offer only wireless wifi internet access, and want to charge for it a flat rate of 20/month. They have wireless APs covering several city blocks - or a whole city. with a physical tie at some city based colo. How do they protect the network - so that only paying customers can be authenticated and use the system?
What i have been thinking so far is that for signing up - you have to purchase/get/rent/whatever - the wireless card from the ISP. This cards MAC is in an ISP DB and its get authenticated. In addition - that MAC is tied back to a username password (or biometric) auth which then validates the user and opens up the port. Is it possible to have an ISP with such a system - that is not too overly paranoid secure - but not just a leech-net?
I think there are three very important things that should be considered when thinking about WiFi ISPs in general:
1. they should be put in place ASAP - even if they arent that secure yet.
2. we (the tech community at large) should fully support them, and pay 20/month for access.
3. wifi ISPs should offer free access to the system for city government - municipal services like fire depts, police, city engineering etc..
WHY? well because we have seen already how the big ass companies handle our bandwidth, our information, our trust and our money.
We should get a community monopoly on these systems as soon as possible. I nkow that I am *done* having any sort of qwest, global crossing, worldcom corrumpany in charge of my access.....
seriously - this is an important issue - and one where we ahve the advantage because these companies are A) almost bankrupt B) dont understand the technology C) typically slow to move on stuff like this. The only problem is that they traditionally have very deep pockets to buy things out.
But with Level 3 trying to buy up all the fiber runs it can - and absorb as many of the IP-traffic-assets as possible - they are looking to run 90% of the data routing market... but the WiFi last mile can and should be a community owned system.
Imagine if the model was changed so that a carrier would have to *pay the community* to be the access provider. If there were several million people in a city - and that city had its own WiFi network - and it was putting out bids for connections to the outside internet - you'd better believe the carriers would be putting down some fat bandwidth at reduced price for that level of market share.
We need to stop thinking so small, have some vision and take over the market and make it the way we want it.
Im not sure if its the same technology, but theres an ISP in my city that offer infrared links up to 10gbps (what they call 'Infra Red Wireless Fiber' -- wireless fiber.. wtf?). On the good side, you can have SOME bandwith using this technology (nothing like the few mbps on wi-fi), on the other side, the beam is very limited, what makes it useless for some aplications. /.'ed .
;o)
The technology is from MRV, in case you wonder.
Indeed, its very secure and have a 99.999% uptime garantee (yeah right).
Now im wondering about using some mirrors to steal.. erm.. borrow some bandwith and never have to worry about getting