Ordinary people should want standardized WLANS
Wireless communications could be a lot better if they were standard. If a large market (practically: either US, Europe, or Japan, or China) would pass a law saying 'all consumer electronic devices must communicate with ieee802.11 WLAN protocol, by the year 2015.'
Sounds like gobbledygook, right? OK, need some de-geeking...
What's a WLAN? It stands for wireless lan, and the 802.11 standard described is why you can use a wireless base station from one company with a computer from any other company. A protocol the language that is used to trade information between two computers. Today, a remote control talks to a tv using a signalling system made by the manufacturer (or some sub-contractor) to communicate with their own controller (or that made by a sub-contractor.) No other device can trade information with your TV.
A cordless phone talks to it's base station using another private signalling system, wireless weather stations, and many other thingums use their own private systems. There are government bureaucracies in most countries (FCC in the US, CRTC in Canada) which say to manufacturers: you can only transmit at such and such a frequency, at such and such a power level. The frequencies are treated as a kind of real-estate. There was a very good reason for this sort of management in most of the twentieth century. People were making radios that talked over each other, and interfered with each other. RADAR works on the same principle as broadcasting. If there was no management then you would have snow on your tv screen everytime the local airport's RADAR swept in your direction. If you think these sorts of problems are imaginary, read this brief account of keyless car locks going nuts near military bases. These sorts of problems result from folks thinking that low power short range communications should not interfere with anything. What nobody counted on was that RADARS and jamming equipment are, by their very nature, very powerful transmitters, and can over power low power transmitters that are very far away.
This sort of problem happens because the devices in question are very simple.
when computers communicate, there is a famous (ok.. famous among geeks) seven layer model ( http://www.freesoft.org/CIE/Topics/15.htm ) There is a physical link layer, which could be over radio waves, over wires, glass fibre, or whatever. Standard electronics for the medium takes care of actually sending and receiving signals. Another basic concept that shows up at this level is 'packets'. Packets are messages limited in size by the medium being used to send them. Packets are usually quite small, they have a clear radio signature at the beginning, a clear radio signature at the end, and the middle has some rules, about how you store information in them: say the first part of the packet should say how long it is, and at the end you will often have a check sum, which is a simply check to see if the packet got clobbered in transit. If any of the rules (start tag, end tag, size should make sense in reference to the start and end, the check sum should match what we received.) are broken, then the physical link layer will normally discard the packet as invalid.
Sorry... what? ... It means that if someone points a RADAR at your car, then with early keyless entry systems, the car just reacts to a fairly simple signal. It will 'see' almost all the traffic, and eventually, just through dumb luck, random noise will be 'decoded' by the receiver, and the trunk will open because of the RADAR. Now theses things are slowly getting smarter, but they are really just re-inventing the wheel that already exist: wireless LANS. A wireless lan, on the other hand, will try to put any signal it receives through the packetization engine, and throw out almost all the random stuff as garbage.
The stuff that makes it through the packet engine, will then have to go through security mechanisms of a wireless lan. There are lots of mechanisms, but basically, the idea is that the base both the remote control, and the reception unit in the car 'know' a 'password.' They use the password to make the message unreadable. Someone who knows the password can make it readable again. So once you get a packet, wireless LAN hardware will try to make the message readable again, based on the shared secret. If it doesn't work, again, the packet is thrown out. The resistance to interference comes, not from having a really good radio, but from how the signal is structured, to make it nearly impossible for random interference to be understood as real commands from a remote that a device should listen to. The shared secret makes it reasonably hard for your neighbour to change your tv's station.
OK, but what about interference? Early cordless phones would buzz when you used them near appliances. They used a single frequency, like a radio or a television, and if an appliance made noise on the frequency, you would get buzz. After a while higher frequencies, like 900 MHz came along, and they moved to 'digital signals' (which means they make it into packets... but each maker does it their own way.) which made things a little better, but there were still problems with interference and crosstalk. So then 'Digital Spread Spectrum' came out. What's that? Well, it means that instead of using one frequency, the cordless phone and base station listen for other radios on a bunch of frequencies, and avoids interference by using (aka "hopping" to) the ones with the least noise.
So when a military RADAR scans at your car, if the car were using wireless LAN technology, the car starts discarding 99% of the packets coming on the frequency it was using, assumes there are others using it, and the remote and car switch to a less crowded one instead.
A radio that has things like frequency hopping, packets and security is what you need when there are a lot of devices sharing the same radio space, without causing gaps in conversations, or trunks of cars to open at random intervals. Common devices can share less radio space, and we can reclaim the frequencies allocated to other uses. Another benefit of this technology is that wlan radios adjust their power levels to only send at the minimum power required to communicate. Those who worry, rightly or wrongly about long term exposure to radio waves, can take comfort that smart radios will use less power, and the total amount of radio transmissions will be reduced by all devices being able to share a single base station.
Today, the hardware for a wlan interface costs on the order of 20$. This is a lot for some forms of consumer electronics (think DVD remote control), but standardization will also drive down costs, since the market for them will be vast, and no-one will have to develop company specific radio hardware, and all devices will be able to listen and talk to eachother.
So it won't cost much, it will allow us to use radio frequencies for other purposes, but what is the win for the consumer? Well, using the same system as computers means you have a gateway to computers. Anything you can send over this short range radio, can be sent to a common base station, and then sent anywhere over the internet.
OK... instead of a cordless phone with a base station for that brand of phone, all the cordless phones ( like this one... http://www.qiiq.com/products/productsQWiFiFONEXUV.htm ) will work with any wireless base station. They use Voice over Internet Protocols, and soft PBX's (like this one: http://www.asterisk.org) implemented on computers to give any home a complete industrial strength phone system. No such thing as a busy tone. Someone phones your home to talk to your teenager. Your spouse is conversing with his/her mother and you can still receive calls at the same time. There would be a few tests to pass before the phone actually rings in the house. Phone numbers of people you know would be let directly through, others would have to answer some questions first. Gone are the days of heat pump salesmen interrupting your dinner. Cell phones are basically history. People will have bandwidth available everywhere, and calls will be free.
If the car and the house speak to each other, you tell your home entertainment system to send the new disney movie to the car, so that the kids can watch it on the way to grandma's, don't have to carry anything. You can use the tv remote to start the car so it is warm when you get there, and find out if you need to get gas, and if the tire pressure is low.
It is hard to come up with good examples of how this will change everything, but it will do it, in some way that we cannot forsee right now. It would be a multi-billion dollar win for society, but it needs a network effect to get started.
This is all easy stuff to do at a technical level. It isn't hard, it just needs people who are in different industries to talk to each other. If you take existing wireless lan technologies, layer web servers on top of it, and XML for communications, then all of these things are just a matter of agreeing on things. proposing a law or a regulatory requirement might give just the push we need.
Sounds like gobbledygook, right? OK, need some de-geeking...
What's a WLAN? It stands for wireless lan, and the 802.11 standard described is why you can use a wireless base station from one company with a computer from any other company. A protocol the language that is used to trade information between two computers. Today, a remote control talks to a tv using a signalling system made by the manufacturer (or some sub-contractor) to communicate with their own controller (or that made by a sub-contractor.) No other device can trade information with your TV.
A cordless phone talks to it's base station using another private signalling system, wireless weather stations, and many other thingums use their own private systems. There are government bureaucracies in most countries (FCC in the US, CRTC in Canada) which say to manufacturers: you can only transmit at such and such a frequency, at such and such a power level. The frequencies are treated as a kind of real-estate. There was a very good reason for this sort of management in most of the twentieth century. People were making radios that talked over each other, and interfered with each other. RADAR works on the same principle as broadcasting. If there was no management then you would have snow on your tv screen everytime the local airport's RADAR swept in your direction. If you think these sorts of problems are imaginary, read this brief account of keyless car locks going nuts near military bases. These sorts of problems result from folks thinking that low power short range communications should not interfere with anything. What nobody counted on was that RADARS and jamming equipment are, by their very nature, very powerful transmitters, and can over power low power transmitters that are very far away.
This sort of problem happens because the devices in question are very simple.
when computers communicate, there is a famous (ok.. famous among geeks) seven layer model ( http://www.freesoft.org/CIE/Topics/15.htm ) There is a physical link layer, which could be over radio waves, over wires, glass fibre, or whatever. Standard electronics for the medium takes care of actually sending and receiving signals. Another basic concept that shows up at this level is 'packets'. Packets are messages limited in size by the medium being used to send them. Packets are usually quite small, they have a clear radio signature at the beginning, a clear radio signature at the end, and the middle has some rules, about how you store information in them: say the first part of the packet should say how long it is, and at the end you will often have a check sum, which is a simply check to see if the packet got clobbered in transit. If any of the rules (start tag, end tag, size should make sense in reference to the start and end, the check sum should match what we received.) are broken, then the physical link layer will normally discard the packet as invalid.
Sorry... what? ... It means that if someone points a RADAR at your car, then with early keyless entry systems, the car just reacts to a fairly simple signal. It will 'see' almost all the traffic, and eventually, just through dumb luck, random noise will be 'decoded' by the receiver, and the trunk will open because of the RADAR. Now theses things are slowly getting smarter, but they are really just re-inventing the wheel that already exist: wireless LANS. A wireless lan, on the other hand, will try to put any signal it receives through the packetization engine, and throw out almost all the random stuff as garbage.
The stuff that makes it through the packet engine, will then have to go through security mechanisms of a wireless lan. There are lots of mechanisms, but basically, the idea is that the base both the remote control, and the reception unit in the car 'know' a 'password.' They use the password to make the message unreadable. Someone who knows the password can make it readable again. So once you get a packet, wireless LAN hardware will try to make the message readable again, based on the shared secret. If it doesn't work, again, the packet is thrown out. The resistance to interference comes, not from having a really good radio, but from how the signal is structured, to make it nearly impossible for random interference to be understood as real commands from a remote that a device should listen to. The shared secret makes it reasonably hard for your neighbour to change your tv's station.
OK, but what about interference? Early cordless phones would buzz when you used them near appliances. They used a single frequency, like a radio or a television, and if an appliance made noise on the frequency, you would get buzz. After a while higher frequencies, like 900 MHz came along, and they moved to 'digital signals' (which means they make it into packets... but each maker does it their own way.) which made things a little better, but there were still problems with interference and crosstalk. So then 'Digital Spread Spectrum' came out. What's that? Well, it means that instead of using one frequency, the cordless phone and base station listen for other radios on a bunch of frequencies, and avoids interference by using (aka "hopping" to) the ones with the least noise.
So when a military RADAR scans at your car, if the car were using wireless LAN technology, the car starts discarding 99% of the packets coming on the frequency it was using, assumes there are others using it, and the remote and car switch to a less crowded one instead.
A radio that has things like frequency hopping, packets and security is what you need when there are a lot of devices sharing the same radio space, without causing gaps in conversations, or trunks of cars to open at random intervals. Common devices can share less radio space, and we can reclaim the frequencies allocated to other uses. Another benefit of this technology is that wlan radios adjust their power levels to only send at the minimum power required to communicate. Those who worry, rightly or wrongly about long term exposure to radio waves, can take comfort that smart radios will use less power, and the total amount of radio transmissions will be reduced by all devices being able to share a single base station.
Today, the hardware for a wlan interface costs on the order of 20$. This is a lot for some forms of consumer electronics (think DVD remote control), but standardization will also drive down costs, since the market for them will be vast, and no-one will have to develop company specific radio hardware, and all devices will be able to listen and talk to eachother.
So it won't cost much, it will allow us to use radio frequencies for other purposes, but what is the win for the consumer? Well, using the same system as computers means you have a gateway to computers. Anything you can send over this short range radio, can be sent to a common base station, and then sent anywhere over the internet.
OK... instead of a cordless phone with a base station for that brand of phone, all the cordless phones ( like this one... http://www.qiiq.com/products/productsQWiFiFONEXUV.htm ) will work with any wireless base station. They use Voice over Internet Protocols, and soft PBX's (like this one: http://www.asterisk.org) implemented on computers to give any home a complete industrial strength phone system. No such thing as a busy tone. Someone phones your home to talk to your teenager. Your spouse is conversing with his/her mother and you can still receive calls at the same time. There would be a few tests to pass before the phone actually rings in the house. Phone numbers of people you know would be let directly through, others would have to answer some questions first. Gone are the days of heat pump salesmen interrupting your dinner. Cell phones are basically history. People will have bandwidth available everywhere, and calls will be free.
If the car and the house speak to each other, you tell your home entertainment system to send the new disney movie to the car, so that the kids can watch it on the way to grandma's, don't have to carry anything. You can use the tv remote to start the car so it is warm when you get there, and find out if you need to get gas, and if the tire pressure is low.
It is hard to come up with good examples of how this will change everything, but it will do it, in some way that we cannot forsee right now. It would be a multi-billion dollar win for society, but it needs a network effect to get started.
This is all easy stuff to do at a technical level. It isn't hard, it just needs people who are in different industries to talk to each other. If you take existing wireless lan technologies, layer web servers on top of it, and XML for communications, then all of these things are just a matter of agreeing on things. proposing a law or a regulatory requirement might give just the push we need.
posted by philobyte at
07:25
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