Pervasive computing is the trend towards increasingly ubiquitous (another name for the movement is ubiquitous computing), connected computing devices in the environment, a trend being brought about by a convergence of advanced electronic - and particularly, wireless - technologies and the Internet. Pervasive computing devices are not personal computers as we tend to think of them, but very tiny - even invisible - devices, either mobile or embedded in almost any type of object imaginable, including cars, tools, appliances, clothing and various consumer goods - all communicating through increasingly interconnected networks.
Modern devices that may serve the ubiquitous computing model include mobile phones, digital audio players, radio-frequency identification tags and interactive whiteboards. Other terms for ubiquitous computing include pervasive computing, calm technology, things that think, everyware, and more recently, pervasive Internet.
Ubiquitous computing encompasses a wide range of research topics, including distributed computing, mobile computing, sensor networks, human-computer interaction, and artificial intelligence.
HISTORY
Pervasive computing is the third wave of computing technologies to emerge since computers first appeared:
o First Wave - Mainframe computing era: one computer shared by many people, via
workstations.
o Second Wave - Personal computing era: one computer used by one person, requiring a
conscious interaction. Users largely bound to desktop.
o Third Wave - Pervasive (initially called ubiquitous) computing era: one person, many
computers. Millions of computers embedded in the environment, allowing technology
to recede into the background.
BACKGROUND
Eight billion embedded microprocessors are produced each year. This number is expected to rise dramatically over the next decade, making electronic devices ever more pervasive. These devices will range from a few millimeters in size (small sensors) to several meters (displays and surfaces). They may be interconnected via wired and wireless technologies into broader, more capable, networks. Pervasive computing systems and services may lead to a greater degree of user knowledge of, or control over, the surrounding environment, whether at home, or in an office or car.There have been calls for more widespread debate on the implications of pervasive computing while it is still at an early stage of development.
PERVASIVE COMPUTING TECHNOLOGIES
Pervasive computing technologies classified in to four converging areas
- Mobile Computing
- Embedded and Applied computing
- RFID and Sensors
- Mobile and sensor networking
Mobile Computing
The widespread use of mobile computing devices has changed the way people compute and vastly expanded research areas in distributed computing and networking. In fact, traditional distributed computing is actually a subset of the broad area of mobile computing. Many topics in "mature" areas like distributed databases, distributed fault tolerance, and resource management now require much additional study, because many traditional assumptions are challenged. Mobile computers operate in more hostile environments, are resource-constrained (limited power, frequent disconnection), and are peripheral-poor.
Mobile computing is changing the way we live and work, as profoundly as the introduction of the automobile did almost a century ago. Key advances in mobile networking, wireless connectivity, mobile information access, content adaptation, data synchronization, technology for notebook and wearable computers, and innovative mobile e-business solutions have come from worldwide research laboratories..
Some of the recent research in mobile computing includes:
WEARABLE DISPLAY OF ATHLETES' STATISTICS
TeamAwear is a basketball jersey that displays real-time information about its wearer's statistics such as their fouls, points, and scores and alerts players when the game is nearly over or when time is running out to shoot. Mitchell Page and Andrew Vande Moere at the Centre of Design Computing and Cognition of the University of Sydney developed the system, which consists of numerous colored electroluminescent panels. A small computer attached to the player's body controls the panels and communicates wirelessly with a server that tracks relevant game statistics. For example, panels on the jersey's side light up to show how many goals the wearer has scored, with each panel representing 10 goals Although the inventors developed the TeamAwear jersey originally for basketball, they claim that it could also work in other fast-paced sports in which player-specific data changes rapidly, such as soccer, volleyball, cricket, and baseball. It could also support emergency teams working in noisy environments where verbal communication is inefficient.
SKYSCOUT
If you've ever looked at the night sky and wondered what stars you were observing, Celestron's SkyScout might be for you. Especially useful for novice astronomers, this handheld device combines GPS technology with a map of the sky to identify, locate, and provide information about celestial bodies. To identify an object of interest, you simply view it through the SkyScout and press the Identify button. SkyScout's technology identifies the object and tells you what it is. To locate a celestial body, you select it from a reasonably easy-touse menu of objects and press the Locate button. SkyScout uses red directional arrows around the eyepiece to guide you to the object in the sky. A nice feature is that the menu shows only objects that should be visible. (Unfortunately, Sky- Scout has no way to know which of those objects are blocked by trees). Finally, the device can educate you about many of the more popular celestial bodies. The information is available both through audio and text and includes facts about the object and its history and mythology. SkyScout's release was delayed in 2006 because of manufacturing problems in one of the components.
NOKIA NSERIES PHONES
Nokia has announced three new mobile phones in its multimedia Nseries, each targeting a different market segment. The N71, N80, and N92 offer a long list of features. The N71, from the Nokia XpressMusic family, offers an FM stereo tuner, a five-band equalizer, and support for audio and video formats including MP3, AAC, eAAC+, WMA, JPEG, and MPEG-4. It offers a 240 _ 320-pixel display and two cameras, one 2-megapixel (1600 _ 1200 pixel) and the other VGA (640 _ 480 pixel). It operates on dual-mode wideband code division multiple access (WCDMA)/GSM and triband GSM. The N80 offers a 352 _ 416-pixel display and a 3-megapixel camera with features including four flash modes, 10 scene modes, manual exposure correction, and four color tones.
Embedded and Applied Computing
Embedded and ubiquitous computing is an exciting new paradigm that provides computing and communication services all the time and everywhere. Its systems are now affecting every aspect of our life to the point that they are hidden inside various appliances. This emergence is a natural outcome of research and technological advances in embedded systems. An Embedded Pervasive Computing Environment is equipped with hardware and software components that autonomously respond to the needs of its occupants. Embedded system is the core part of pervasive computing and it deals with various applications like wearable computer architecture and applications, sensor networks, real-time embedded operating systems, embedded servers, embedded system networking, address-free routing, smart spaces, dynamic service discovery, mobility and case studies. Some of the on-going researches in embedded systems include:
ROLLABLE DISPLAY
Who hasn't dreamt of a display that rolls up when not in use? Phillips took one step toward this dream on a commercial scale when it formed venture company Polymer Vision in January 2004. Polymer Vision recently reported that it can make a flexible display with a 2 cm bending radius. The display is an organics-based, QVGA (320 240 pixels) active-matrix display, 5 in. on the diagonal and 85 dpi. The display layers a 200-micron thick, reflective Electronic-Ink display from E Ink Corporation (www.eink.com) on top of a 25-micron thick, active-matrix plane.
USING LANDLINES FOR CELLULAR CALLS
Xcelis (www.xcelis.com) has developed an innovative product for coupling cell phones and landline handsets. The Pantheon (see Figure 3) plugs into a landline phone line and, using a Bluetooth connection, routes incoming and outgoing voice calls and data from users' cell phones to their landline handsets. The Pantheon indicates incoming mobile calls with a distinctive ring. While the mobile call is in progress, it doesn't tie up the landline, meaning you can still receive landline calls through your other telephones.
You need one device for each landline telephone that you want to multiplex. When making calls from your landline, you can choose whether to use your cell phone or landline account. The Pantheon provides additional features, including conferencing a landline call and a mobile call, accessing a user's mobile phonebook from a landline phone, and switching mid-call from a landline phone to a mobile phone. The Pantheon is also compatible with voice over IP handsets.
BIONIC ARM
Todd Kuiken at the Rehabilitation Institute of Chicago at the Northwestern Feinberg School of Medicine has developed a thought-powered bionic arm. The arm is based on a pioneering muscle reinnervation procedure that takes an amputee's nerves and connects them to a healthy muscle. Doctors take nerves that used to go to the arm and connect them to chest muscles. The nerves grow into the chest muscles and can contract the muscle when the patient thinks, for example, "Close hand." Electrical signals from the chest muscles drive the arm. Surface electrodes sense these impulses from the pectoral muscle and carry them through to the arm, causing it to move. Jesse Sullivan, a high-power lineman who had both of his arms amputated after being severely electrocuted, is the first patient to be outfitted with bionic arms. The arms have enabled him to do daily activities such as put on socks, shave, eat dinner, take out the garbage, carry groceries, and vacuum. Future generations of the arm will incorporate the sense of touch and feeling.
Mobile and Sensor networking
Sensor mobility allows better coverage in areas where events occur frequently in many sensor networks, considerably more units are available than necessary for simple coverage of the space. Augmenting sensor networks with motion can exploit this surplus to enhance sensing while also improving the network's lifetime and reliability. When a major incident such as a fire or chemical spill occurs, several sensors can cluster around that incident. This ensures good coverage of the event and provides immediate redundancy in case of failure another use of mobility comes about if the specific area of interest (within a larger area) is unknown during deployment. For example, if a network is deployed to monitor the migration of a herd of animals, the herd's exact path through an area will be unknown beforehand. But as the herd moves, the sensors could converge on it to get the maximum amount of data. In addition, the sensors could move such that they also maintain complete coverage of their environment while reacting to the events in that environment. In this way, at least one sensor still detects any events that occur in isolation, while several sensors more carefully observe dense clusters of events. On going researches in sensor networking includes:
WORLDWIDE BROADBAND WIRELESS ACCESS
Option is offering a PC data card that can access wireless broadband worldwide. You can use the GlobeTrotter GT Max on the 850, 1900, or 2100 MHz HSDPA/UMTS (High-Speed Downlink Packet Access/Universal Mobile Telecommunications System) networks and the 850, 900, 1800, or 1900 MHz EDGE/ GPRS (General Packet Radio Service) bands. The card can support data speeds up to 1.8 megabits per second on HSDPA networks, 384 kilobits per second on UMTS networks, 247 Kbps on EDGE networks, and 85 Kbps on GPRS networks. It's a Type II PCMCIA (Personal Computer Memory Card International Association)-compliant 3.3-V PC card and includes a novel "Butterfly" retractable antenna that doesn't require users to remove the card when it's not in use. Numerous wireless carriers offer the card, including Cingular, which recently announced that it would offer it under two plans. One plan will cost users 0 per month and includes unlimited data use in the US and 100 Mbytes of downloads in Canada and Mexico. The other plan will cost 0 and will include unlimited use in the US and 100 Mbytes of downloads in 24 countries including Australia, China, France, Italy, and Germany.
THE SELF-CLEANING HOUSE OF THE FUTURE
The house of the future won't need cleaning. Not by humans, leastways. Every surface will be dirt-repellent and antibacterial; and on the floors the vacuum cleaner is buzzing around - all on its own. The outer walls are all glass which can be screened off entirely and the interior surface used as TV screen. The scenario of the self-cleaning house belongs in the distant future, maybe 20 years from now. With the rapidly increasing development of nanotechnology we have seen for the past few years, it is not easy to predict a specific time span and it will be not only self-cleaning but also self-sufficient, energy wise. Today, the Australians are already experimenting with nanoglass-houses where the glass can be treated with a pigmented coating rendering the entire house non-transparent - the roof included.
WALL SENSORS
The house of the future will be capable of alerting its owner if it's in need of repair. The building materials will, of course, be susceptible to wear and tear due to wind and weather, and they will therefore have built-in sensors. When these sensors appear, the house computer will receive a message that this particular section needs repair. A variety of conditions are similarly monitored. This way, house owners can cheaply repair worn materials and avoid major, expensive repairs after the damage has been done.
THE INTELLIGENT HOUSE
The intelligent house of the future will alert the fire brigade in case of fire when you're at work. Or, if you've got a leaky water pipe, it will get hold of the plumber. Multifunctional sensors throughout the house will keep an eye on heating, lights, indoor climate etc. The house of the future will comprise two major digital gateways. One gateway will be the media server which comprises the complete collection of the family's music, films, photos etc. Another feature will be the highly secure homegateway - a server communicating with the many sensors distributed all over the house to monitor heating, indoor climate etc. The two gateways are separate entities, as the security on the homegateway needs to be exceedingly tight. This gateway should not be exposed to hacking, which could have fatal consequences with respect to security. If, for instance, the motion detectors are tampered with, the burglar alarm might be disabled. Likewise, it would be an unpleasant experience to come home to a room temperature of 40 degrees Celcisus, because someone is mad at you and has hacked into your system to change the temperature settings Thus, each room in the house of the future will be equipped with small sensors. - Larger rooms may have several. They will measure the physical conditions in the room and communicate with the homegateway which will then take care of the Internet-based communication out of the house.
RFID and Sensors
Radio frequency identification (RFID) technology uses radiofrequency waves to transfer data between readers and movable tagged objects without line of sight. RFID holds the promise of real-time identifying, locating, tracking and monitoring physical objects, and can be used for a wide range of pervasive computing applications. To achieve these goals, RFID data have to be collected, transformed and expressively modeled as their virtual counterparts in the virtual world. RFID data, however, have their own unique characteristics - including aggregation, location, temporal and history-oriented - which have to be fully considered and integrated into the data model. The diversity of RFID applications pose further challenges to a generalized framework for RFID data modeling. Today, Radio Frequency Identification enjoys an enormous interest as the first widely deployed pervasive technology as not only from the standpoint of research
but also from Corporate practices future. Some of the recent researches in RFID technologies include:
TAGS EVERYWHERE
The Ubiquitous ID Center provides the infrastructure for managing electronic tags embedded in or attached to objects in a ubiquitous environment. The center developed the ucode, a multicode tag that automatically identifies information stored in bar codes, RFID chips, smart cards, and electronic tags embedded in virtual entities such as software and electronic money. Comparable to the ISBN (International Standard Book Numbering) code used in the publishing industry, the UID Center assigns unique numbers to each tag and stores data relating to the object in database servers. The ucode tags use a 128-bit code that can be extended in 128-bit units, creating a virtually limitless string of numbers. To navigate this tagged environment, the UID Center developed the Ubiquitous Communicator, a PDA-like device that reads ucode tags and retrieves the relevant data from the UID Center's server database. The standard UC has a host of features, including wireless LAN, Voice over Internet Protocol, infrared data communication, and a biometric reader. Apart from the PDA-like version, the UID Center developed a cell phone model and a watch style. At home, it will serve as the remote control for home entertainment systems and appliances. In the office, it will read a printer's tag and order a replacement cartridge as needed
FROM UPC TO RFID
Smart packaging became a possibility with the introduction of small battery-free microprocessors called RFID (Radio Frequency Identification Device) tags. Though these have been commercially available for a number of years, they have been too clunky and too expensive for use in packaging. This situation is changing rapidly: industry experts predict that the price per tag will fall to under 10 cents each in the course of five years or so. The new generation of RFID tags can take the form of a sticker like the classic bar codes, or they can be directly integrated into the packaging material itself. They consist of a silicon microprocessor and some form of radio antenna--conductive carbon ink is replacing the more expensive metal coil of earlier tag types. This radio antenna functions as both input/output channel and power source. Electricity is generated in the antenna by either a magnetic field or a radio signal; the tag responds by sending out a radio signal in turn. This reply signal contains metadata stored on the chip, typically an ID number .With the help of RFID readers--in our cell phones, in supermarket freezers and check-outs, in our private fridges--we will be able to retrieve information about a particular item based on its ID number. In fact, the first cell phones with built-in readers, based on NFC (Near Field Communication) technology, are already on the market.
NEXT-GENERATION TAGS
The smart tags which will soon begin replacing bar codes in our supermarkets are actually pretty dumb: their only ability is reciting their ID code on command. With the next generation of MEMS tags, the epithet 'smart' will be more fitting. MEMS (Micro Electro Mechanical Systems) tags are able to perform measurements and calculations. MEMS tags are especially interesting in connection with extremely perishable goods like milk and meat. Studies have shown that the 'sell by' date on such products is dubious at best: milk only stays fresh until the given date as long as it is stored at the right temperature. Storage is the key term here; for example, that the temperature in around one-fifth of the meat and dairy cases in American supermarkets is three or four degrees too high. And what happens when we leave the milk out on the kitchen counter all morning? MEMS tags in smart packages will be able to take the milk's temperature every fifteen minutes. The measurements are then sent to a small microprocessor which calculates the milk's estimated freshness.
FOOD SAFETY
The fridge of the future will have a door with a built-in scanner for reading the digital tags on food packages. This way the refrigerator will always keep abreast of what is put into it; and the screen on the door can supply an overview of what's behind the door. By scanning all foodstuffs, you will always have an updated listing of your current supplies - canned and frozen food included. In other words: the refrigerator comes to play the part of digital administrator of the kitchen. Should you e.g. keep food approaching its expiry date, the fridge will alert you. The product can then be used at once, and you avoid having to throw away food. The screen is connected to the Internet, and each and every chip tagged to the packaging will represent a Web site which can be visited by the fridge as the food products are stowed away. Thus it can check for any warnings issued for this particular product. We all remember instances of contaminated food which, undetected by producers, have ended up in supermarkets and, consequently, household fridge or freezer. In such cases, an alert from the refrigerator could reduce the risks considerably. Since the fridge frequently runs automatic checks on the net, users are no longer dependent on radio and TV alerts.
Editor:
Mr.S.Vijayakumar
Research Associate - TIFAC-CORE
Velammal Engineering College
Chennai - 600 066
Email: Vijayece2002@yahoo.co.in
