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The Future Of Wireless Sensor Networks
Frisky070802 writes "In the 12/03 Wired, Intel's Tiny Hope for the Future describes a fundamental transformation as Intel's Research director David Tennenhouse realized the importance of sensor networks. He saw a Berkeley project on 'motes,' little sensors that communicate on ad-hoc wireless networks. 'The company now foresees networks consisting of thousands of motes, located wherever there's a need for data collection, streaming real-time data to one another and to central servers. Intel imagines the day when every assembly line, soybean field, and nursing home on the planet will be peppered with motes, prodding factory foremen to replace faulty machines, farmers to water fields, and nurses to check on something unusual in room E214.' Intel was impressed enough with the technology to fund a whole 'lablet' to develop it. Intel sees a huge potential market in developing both the sensors and the computation to process the huge amounts of sensor information. If this rings any bells, note that the Intel lablets are also behind the Planetlab Internet emulator, previously discussed in Slashdot."
Having said that, it's not quite as cut-and-dried as you mention. The primary differences from conventional wireless networks like 802.11 are (1) miniaturization, (2) strict power constraints, (3) disposable nature (i.e. ultra-low cost components req'd), and (4) self-organizing. AFAIK it's still an area of active and open research.
I saw Berkeley and Intel also present on this technology at O'Reilly's Emerging Technology Conference in 2003. The presentation synopsis is here, although the presentation sadly is not:
e _sess/3797
o rks.htm
:)
http://conferences.oreillynet.com/cs/et2003/view/
They are doing amazing sci-fi type stuff with their Motes already, it was a pretty amazing presentation, touching on swarm behavior, conspiracy theories, technical deployment issues, and just plain good-old fun hackery. The wired article really should have mentioned that serious hobbyists can purchase a mote starter kit and other stuff here:
http://www.xbow.com/Products/Wireless_Sensor_Netw
Note that there is a classroom starter kit. I would think this sort of stuff would get high-schoolers really excited about science. A great stocking stuffer for your local high-school (although at $1,000 or more maybe a little out of my budget).
Imagine a Beowulf cluster of..... never mind.
- "When you want something with all your heart, the entire universe conspires to give it to you" -Paulo Coelho
Security will definitely be an issue, since with all the transmitting, anyone close enough will be able to pick up the frequencies (though probably not your average joe script kiddie).
Esoteric reference.
Vinge wrote about localizers in the very good A Deepness in the Sky after talking to the people at Ather Wire and Location.
I went to a presentation by the principals of Aether Wire about eight years ago, at that point they had working localizers that were about the size of a stack of two or three quarters. These devices use Ultra-Wide-Band signalling for extremely low-power low-probability-of-intercept communication. The UWB pulse-trains they were using were remarkably able to penetrate thin metal walls (e.g. a refrigerator.)
UWB technology has a long and sordid history of patent fights, and fights with the FCC over how much interference it would cause. For the conspiracy theorists out there, some suspect that the gov't would like to squash UWB because it's so easy to build almost undetectable (not just undecipherable) radios.
thad
I love Mondays. On a Monday, anything is possible.
It is actually quite opposite. UWB is very difficult to build, that's why it does not work outside of a lab. Any RF engineer will give you ten most obvious reasons why it is difficult, starting from the antenna's inability to operate in such a wide band.
the Planetlab Internet emulator
Planet-Lab is not an emulator. It is a group of computers distributed across the globe that use the real internet. People write distributed apps and run them on different vantage points spread out on the net to measure real internet performance, test their app etc.
You could build an interesting mesh out of all those WiFi boxes. Hopefully for better uses than this idiot.
One line blog. I hear that they're called Twitters now.
Some researchers from UC Berkeley's Smart Dust project have founded a startup in Berkeley called Dust, Inc.
cpeterso
ATMega128 7.3 MHz microcontroller
4 KB RAM, 128 KB PROGRAM EEPROM,
512 KB flash memory for measurements
433 MHz wireless radio, CC1000 transciver,
30 messages per second, 29 bytes in each message
radio range is about 100-300 feet
runs on two AA batteries for 3 days continuously
various pluggable sensor boards
The motes run the TinyOS, freely available from sourceforge
The Berkeley guys are working on the dust mote, 1 mm2 target size including the radio chip. The biggest limitation now is the battery power and the radio range. Even if they can get the size down to "dust", the antenna HAS TO BE 1/4 of the radio wave length. For the 433 MHz version this is around 8-10 inches! So these dust motes will have "tails". Eventually, these could painted on the wall, or dumped from the air for millitary applications. Lot's of unsolved problems. For sensor networks, how do you obtain large amount of data through a few base stations? Smart aggregation and routing protocols need to be employed, and the network must process the data by itself.
Just my 2c.
Being a graduate student at MIT working on sensor networks, I have to mention our project. : )
A MPShome.html
http://www-mtl.mit.edu/research/icsystems/uamps/u
The uAMPS project will involve designing integrated circuits that realize wireless sensor networks. There are students researching low power integrated circuits - both analog and digital. I'm doing the wireless stuff.
You have to be careful to separate the hype from reality regarding sensor networks, but there are definitely some cool applications. One thing that I think will definitely help things progress is the new 802.15.4 standard (Zigbee).
doodles
Wireless sensor networks are not new; there is even a textbook published recently on them (Wireless Sensor Networks: Architectures and Protocols). Many corporations have active WSN programs, including:
Motorola
Ember and
Figure 8 Wireless.
University research programs, in addition to Berkeley, include:
UCLA WINS
MIT uAMPS
plus those sposored by DARPA.
The IEEE 802.15.4 standard, available here, was designed to support such networks. The ZigBee Alliance, an industrial consortium of over 60 companies, is the marketing and compliance arm of the 802.15.4 standard, as the Wi-Fi Alliance is to 802.11. The vitality of the ZigBee Alliance, which had over 350 attendees at its recent open house in Silicon Valley, is an indication that this technology is moving from research into commercialization; the commercialization of wireless sensor networks is the real significance of the Wired article.
Exactly right. Security, in wireless sensor networks, means more than just encryption (for privacy), however. In many applications it's more important to have message integrity and sender authentication, meaning that the recipient is guaranteed that the message hasn't been altered, and that it was from who it says it was from. For example, having an encrypted message from a short-range wireless light switch is often of little utility; people around can see the light come on (perhaps through a window), so you're not really protecting anything. However, as the parent poster says, you really don't want some car of script kiddies driving through your neighborhood randomly turning lights on and off at 2 AM. The wireless lights need to know that the messages they receive are from their associated switches, not from some 3l33t d00dz; that's the function of message integrity and source authentication checking.
Recognizing the importance of these types of security, the IEEE 802.15.4 standard, available here, employs the Advanced Encryption Standard for encryption, message integrity, and sender authentication. The ZigBee Alliance specifies key transport protocols, key management, and other higher layer security functions.