Electronics World

NANO TECHNOLOGY

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DEFINITION:<br />
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The  computer  has  already  gone  through a  dynamic revolution.  Thirty years ago,  computers   were  the   size of  a    room    and incredibly slow.  Few people probably would have imagined supercomputers that  can do over  a  trillion  calculations per  second.  Today, the  average person's desktop computer is more powerful than the fastest computers were 30 years ago.  The only way this can continue is if a new type of computer is developed.  This computer is known as a nano computer.<br />
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NANOTECHNOLOGY:<br />
                                       <br />
Nanotechnology is an exciting emerging science and technological field that is making a splash in 2002. Nanotechnology involves man’s ability to create and manipulate molecules structures to create potentially new materials, devices, machines or objects. A nanometre is a billionth of a metre, that is, about 1/80,000 of the diameter of a human hair, or 10 times the diameter of a hydrogen atom.<br />
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If you blew up a baseball to the size of the earth, the atoms of the baseball would be about the size of grapes. If you could take a ruler and measure 10 atoms side by side, you would have a nanometer. The World is on the brink of a technological revolution beyond any human experience. It has the potential to bring wealth, health and education to every person on the planet. And it will be able to do this without consuming natural resources or spewing pollution into the environment. Nanotechnology is about building things atom by atom, molecule by molecule.<br />
The goal of nanotechnology is to build tiny devices called nanomachines. To build things on such a small scale, you have to be able to manipulate atoms individually.<br />
                                                                             (i)<br />
The challenge of nanotechnology is to place atoms precisely where you wish on a structure.<br />
Scientists can now construct natural proteins and even synthesize new ones with novel properties never seen in nature. With enough understanding, we may be able to turn proteins into microscopic tools to do the jobs we want.<br />
In the future, Nanotechnology will let us take off the boxing gloves. We'll be able to snap together the fundamental building blocks of nature easily, inexpensively and in most of the ways permitted by the laws of physics.<br />
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TYPES OF NANOCOMPUTERS  :<br />
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1. Nano electronic computers<br />
2. Nano mechanical computers<br />
3. Nano chemical and biochemical computers<br />
4. Nano Quantum computers                     <br />
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 DRAWBACKS  :<br />
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Proponents predict that nanotechnology will ignite the industrial revolution of the 21st century, the effects of which will have a greater impact on the world’s population than antibiotics, integrated circuits, and human-made polymers combined. Now that scientists have the tools and are developing the skills to manipulate nature’s building blocks, nanotech enthusiasts tout some mind-bending scenarios.<br />
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SOME APPLICATIONS OF NANOTECHNOLOGY WHICH ONE CAN’T IMAGINE IN THEIR DREAMS:<br />
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·       Self-assembling consumer goods<br />
·       Computers billions of times faster<br />
·       Extremely novel inventions (impossible today)<br />
·       Safe and affordable space travel<br />
·       Medical Nano... virtual end to illness, aging, death<br />
·       No more pollution and automatic cleanup of already existing pollution<br />
·       Molecular food syntheses... end of famine and starvation<br />
·       Access to a superior education for every child on Earth<br />
·       Reintroduction of many extinct plants and animals<br />
·       Terra forming here and the Solar System<br />
·       In a world of information, digital technologies have made copying fast, cheap , and perfect, quite independent of cost or complexity of the content. What if the same were to happen in the world of matter? The production cost of a ton of terabyte RAM chips would be about the same as the production cost of steel. Design costs would matter, production costs wouldn't.<br />
·    By treating atoms as discrete, bit-like objects, molecular manufacturing will bring a digital revolution to the production of material objects. Working at the resolution limit of matter, it will enable the ultimate in miniaturization and performance. By starting with cheap, abundant components--molecules-and processing them with small, high-frequency, high-productivity machines, it will make products inexpensive. Design computers that each execute more instructions per second than all of the semiconductor CPUs in the world combined.<br />
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· Taking all of this into account, it is clear that Nanotechnology should improve our lives in any area that would benefit from the development of better, faster, stronger, smaller, and cheaper systems.<br />
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NANO TECHNOLOGY

DEFINITION: The computer has already gone through a dynamic revolution. Thirty years ago, computers were the size of a room and incredibly slow. Few people probably would have imagined supercomputers that can do over a trillion calculations per second. Today, the average…

02Oct2015

Digital Alarm Clock

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What is a Digital Alarm Clock:<br />
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A digital clock is a one kind of clock used to display the time in the form of digital includes  symbols or numerals. These clocks are frequently connected with electronic drives, but the term digital  refers only to the LCD display, not to the drive mechanism. The digital clock circuit uses the 50-60hz oscillation of AC power.Most digital alarm clocks display the hour of the day in the form of 12 hours or 24 hours with an indication of AM or PM. Most digital alarm clocks use LCD display, seven segment display or VFD.<br />
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Digital clocks run with mains electricity and must be reset the time when the power is off. Most of the clocks don’t have a battery back up, so this will cause to fail to generate an alarm sound at the fixed time. To overcome this problem, many digital alarm clocks are available to operate with a battery during the power outage. Commercial digital clocks are generally more consistent than consumer clocks. Because, these clocks give backup to maintain the time using multi decade battery during power off.<br />
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Digital Alarm Clock

What is a Digital Alarm Clock: A digital clock is a one kind of clock used to display the time in the form of digital includes symbols or numerals. These clocks are frequently connected with electronic drives, but the term digital refers only to the LCD display, not to the drive mechanism. The di…

02Oct2015

DIGITAL WATER MARKING

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<b>Definition: </b><br />
A digital watermark is a digital signal or pattern inserted into a digital document such as text, graphics or multimedia, and carries information unique to the copyright owner, the creator of the document or the authorized consumer.<br />
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<b>Introduction:</b><br />
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Digital watermarking is a technique which allows an individual to add hidden copyright notices or other verification messages to digital audio, video, or image signals and documents. Such hidden message is a group of bits describing information pertaining to the signal or to the author of the signal (name, place, etc.).<br />
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The technique takes its name from watermarking of paper or money as a security measure. Digital watermarking is not a form of steganography, in which data is hidden in the message without the end user's knowledge, although some watermarking techniques have the steganographic feature of not being perceivable by the human eye.<br />
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The enormous popularity of the World Wide Web in the early 1990's demonstrated the commercial potential of offering multimedia resources through the digital networks. Since commercial interests seek to use the digital networks to offer digital media for profit, they have a strong interest in protecting their ownership rights. Digital watermarking has been proposed as one way to accomplish this.<br />
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A digital watermark is a digital signal or pattern inserted into a digital image. Since this signal or pattern is present in each unaltered copy of the original image, the digital watermark may also serve as a digital signature for the copies. A given watermark may be unique to each copy (e.g., to identify the intended recipient), or be common to multiple copies (e.g., to identify the document source).<br />
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In either case, the watermarking of the document involves the transformation of the original into another form. This distinguishes digital watermarking from digital fingerprinting where the original file remains intact, but another file is created that "describes" the original file's content. As a simple example, the checksum field for a disk sector would be a fingerprint of the preceding block of data. Similarly, hash algorithms produce fingerprint files.<br />
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<b>Difference between ``copy protection'' and ``copyright protection’’</b><br />
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Copy protection attempts to find ways, which limits the access to copyrighted material and/or inhibit the copy process itself. Examples of copy protection include encrypted digital TV broadcast, access controls to copyrighted software through the use of license servers and technical copy protection mechanisms on the media. A recent example is the copy protection mechanism on DVDs. However, copy protection is very difficult to achieve in open systems, as recent incidents (like the DVD hack - DeCss) show.<br />
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Copyright protection inserts copyright information into the digital object without the loss of quality. Whenever the copyright of a digital object is in question, this information is extracted to identify the rightful owner. It is also possible to encode the identity of the original buyer along with the identity of the copyright holder, which allows tracing of any unauthorized copies. The most prominent way of embedding information in multimedia data is the use of digital watermarking.<br />
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Whereas copy protection seems to be difficult to implement, copyright protection protocols based on watermarking and strong cryptography are likely to be feasible.<br />
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<b>History:</b><br />
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The term "digital watermark" was first coined in 1992 by Andrew Tirkel and Charles Osborne, in their paper: A.Z.Tirkel, G.A. Rankin, R.M. Van Schyndel, W.J.Ho, N.R.A.Mee, C.F.Osborne. “Electronic Water Mark”. DICTA 93, Macquarie University. p.666-673.<br />
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The term used by Tirkel and Osborne was originally used in Japan-- from the Japanese-- "denshi sukashi" -- literally, an "electronic watermark".<br />
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Paul LevinsonFuture of the Information Revolution (1997), where he called for the use "smart patent numbers" (p. 202), or the embedding of electronic chips in every piece of technology, which would give an updated listing of all of its inventors.<br />
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Whereas a digital watermark can be a form of steganography, e.g., the digital watermark is hidden in plain view. Functionally, the term "digital watermark" is used to describe that which enables differentiation between copies of the "same" content in an imperceptible manner. Many watermarking systems take this a step further, hiding the data so that attempts at erasure results in degradation of the quality of the content.<br />
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<b>The Purpose of Digital Water Marking:</b><br />
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Two types of digital watermarks may be distinguished, depending upon whether the watermark appears visible or invisible to the casual viewer. Visible watermarks are used in much the same way as their bond paper ancestors, where the opacity of paper is altered by physically stamping it with an identifying pattern. This is done to mark the paper manufacturer or paper type. One might view digitally watermarked documents and images as digitally "stamped"<br />
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Invisible watermarks, on the other hand, are potentially useful as a means of identifying the source, author, creator, owner, distributor or authorized consumer of a document or image. For this purpose, the objective is to permanently and unalterably mark the image so that the credit or assignment is beyond dispute. In the event of illicit usage, the watermark would facilitate the claim of ownership, the receipt of copyright revenues, or the success of prosecution.<br />
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Watermarking has also been proposed to trace images in the event of their illicit redistribution. Whereas past infringement with copyrighted documents was often limited by the unfeasibility of large-scale photocopying and distribution, modern digital networks make large-scale dissemination simple and inexpensive. Digital watermarking makes it possible to uniquely mark each image for every buyer. If that buyer then makes an illicit copy, the illicit duplication may be convincingly demonstrated.<br />
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<b>Techniques for Water Marking:</b><br />
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Watermarking techniques tend to divide into two categories, text and image, according to the type of document to be watermarked. Techniques for images: Several different methods enable watermarking in the spatial domain. The simplest (too simple for many applications) is to just flip the lowest-order bit of chosen pixels in a gray scale or color image. This will work well only if the image will not be subject to any human or noisy modification.<br />
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A more robust watermark can be embedded in an image in the same way that a watermark is added to paper. Such techniques may superimpose a watermark symbol over an area of the picture and then add some fixed intensity value for the watermark to the varied pixel values of the image.<br />
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The resulting watermark may be visible or invisible depending upon the value (large or small, respectively) of the watermark intensity. One disadvantage of spatial domain watermarks is that picture cropping (a common operation of image editors) can be used to eliminate the watermark.<br />
Spatial watermarking can also be applied using color separation. in this way, the watermark appears in only one of the color bands. This renders the watermark visibly subtle such that it is difficult to detect under regular viewing.<br />
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However, the watermark appears immediately when the colors are separated for printing or xerography. This renders the document useless to the printer unless the watermark can be removed from the color band. This approach is used commercially for journalists to inspect digital pictures from a photo-Stackhouse before buying un-watermarked versions.<br />
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Watermarking can be applied in the frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT). In a similar manner to spatial domain watermarking, the values of chosen frequencies can be altered from the original. Since high frequencies will be lost by compression or scaling, the watermark signal is applied to lower frequencies, or better yet, applied adaptively to frequencies that contain important information of the original picture (feature-based schemes).<br />
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Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation, this method is not as susceptible to defeat by cropping as the spatial technique. However, there is more of a tradeoff here between invisibility and decodability, since the watermark is in effect applied indiscriminately across the spatial image.<br />
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Watermarking can be applied to text images as well. Three proposed methods are: text line coding, word space coding, and character encoding. For text line coding, the text lines of a document page are shifted imperceptibly up or down. For a 40-line text page, for instance, this yields 2**40 possible codewords. For word-shift coding, the spacing between words in a line of justified text is altered<br />
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For character coding, a feature such as the endline at the top of a letter, "t" is imperceptibly extended. An advantage of these methods over those applied to picture images is that, by combining two or three of these to one document, two documents with different watermarks cannot be spatially registered to extract the watermark. Of course, the watermark can be defeated by retyping the text.<br />
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<b>Briefly following Technologies in particular type of water marking.</b><br />
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1) Techniques for Texts<br />
    1.1) Line Coding: Change the spacing between lines.<br />
    1.2) Word-shift Coding: Change the spacing between words.<br />
    1.3) Character Encoding: Alter the shapes of characters.<br />
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2) Techniques for Images<br />
   2.1)Spatial Watermarking: Just change some of the values of the pixels in       the lower bit plane;              e.g., Change some of the bits from 1 to 0 or 0 to 1.<br />
   2.2)Frequency Domain Watermarking: First convert the image to the frequency domain and then              apply the watermark in the low frequency regions.<br />
   3.3)Checksum Technique for images<br />
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•Watermark is formed from the 7 most significant bits of each pixel.<br />
•Eight 7-bit segments (from eight different pixels) are concatenated and the final checksum is thus 56-bit.<br />
•Locations of the pixels that are to contain one bit each of the checksum are randomly chosen.<br />
•These pixel locations along with the checksum form the watermark, W.<br />
•Last bit of each pixel is then changed to the corresponding checksum bit.<br />
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DIGITAL WATER MARKING

Definition: A digital watermark is a digital signal or pattern inserted into a digital document such as text, graphics or multimedia, and carries information unique to the copyright owner, the creator of the document or the authorized consumer. Introduction: Digital watermarking is a technique whi…

25Apr2015

DIGITAL SIGNATURE

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<b>INTRODUCTION:</b><br />
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In today's commercial environment, establishing a framework for the authentication  of computer-based information requires a familiarity with concepts and professional skills from both the legal and computer security fields. Combining these two disciplines is not an easy task. Concepts from the information security field often correspond only loosely to concepts from the legal field, even in situations where the terminology is similar. For example, from the information security point of view, "digital signature" means the result of applying to specific information certain specific technical processes described below. The historical legal concept of "signature" is broader. It recognizes any mark made with the intention of authenticating the marked document.<br />
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<b>HISTORY:</b><br />
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 It is probably not surprising that the inventors of writing, the Sumerians, were also the inventors of an authentication mechanism. The Sumerians used intricate seals, applied into their clay cuneiform tablets using rollers, to authenticate their writings. Seals continued to be used as the primary authentication mechanism until recent times.<br />
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Use of signatures is recorded in the Talmud (fourth century), complete with security procedures to prevent the alteration of documents after they are signed. The Talmud even describes use of a form of "signature card" by witnesses to deeds. The practice of authenticating documents by affixing handwritten signatures began to be used within the Roman Empire in the year AD 439, during the rule of Valentinian III. The subscripto - a short handwritten sentence at the end of a document stating that the signer "subscribed" to the document - was first used for authenticating wills.<br />
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The practice of affixing signatures to documents spread rapidly from this initial usage, and the form of signatures (a hand-written representation of one’s own name) remained essentially unchanged for over 1,400 years. It is from this Roman usage of signatures that the practice obtained its significance in Western legal tradition.<br />
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<b>When do you need to verify identity?</b><br />
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New ways of verification are being developed daily.  Biometrics and other methods keep getting formulated and incorporated into the information technology industry.   One interesting biometric authentication mechanism developed by a leading Japanese biometric company has found a way to get your DNA into a pen.  You sign a document and it is digitally scanned.  This document then can be scanned in the future to verify its authenticity. Identity should be verified when ever there is doubt of the 3rd party being whom they say they are or when there is personal information at risk.  Personal information like credit card details and banking information should be kept safe using digital certification as one of the security layers. <br />
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Some banking institutions require that a user verifies his/her identity by validating identification credentials using a digital certificate. Important e-mail can also use Digital signatures that verify that the e-mail is from the originating sender and that it has not been tampered with. <br />
<br />On many occasions users are unsure if they are dealing with reputable suppliers of institutions.  Digital certification gives the user a sense of legitimacy and formalizes the process.  It ensure that the company that the user is dealing with has a registration with a trusted authority and that the transaction is guaranteed to be done with the intended parties.<br />
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<b>DIGITAL SIGNATURE:</b><br />
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Digital signatures are a way to ensure the integrity of a message or other data using public key cryptography. Like traditional signatures written with ink on paper, they can be used to authenticate the identity of the signer of the data. However, digital signatures go beyond traditional signatures in that they can also ensure that the data itself has not been altered.<br />
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This is like signing a check in such a way that if someone changes the amount of the sum written on the check, an “Invalid” stamp becomes visible on the face of the check.Digital signatures take the concept of traditional paper-based signing and turn it into a digital "fingerprint". This "fingerprint", or coded message, is unique to both the document and the signer.<br />
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The digital signature ensures that the signatory is indeed the originator of the message.  Any changes made to the document after it was signed invalidate the signature, thereby protecting against forgery. Digital signatures help organizations sustain signer authenticity, accountability, data integrity and non-repudiation of documents and transactions.<br />
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<b>Reasons for using digital security.</b><br />
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•It insures by means of verification and validation that the user is whom he/she claims to be.  This is done by combine the users credential to the digital certificate and in turn this method uses one point of authentication. '<br />
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•Digital certificates insure data Integrity giving the user piece of mind that the message or transaction has not been accidentally or maliciously altered.  This is done cryptographically. <br />
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•Digital certificates ensure confidentiality and ensure that messages can only be read by authorized intended recipients.<br />
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•Digital certificates also verify date and time so that senders or recipients can not dispute if the message was actually sent or received.<br />
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<b>The components that a digital signature comprise of</b><br />
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1.Your public key: This is the part that any one can get a copy of and is part of the verification system.<br />
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2.Your name and e-mail address: This is necessary for contact information purposes and to enable the viewer to identify the details.<br />
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3.Expiration date of the public key: This part of the signature is used to set a shelf life and to ensure that in the event of prolonged abuse of a signature eventually the signature is reset.<br />
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4.Name of the company: This section identifies the company that the signature belongs too.<br />
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5.Serial number of the Digital ID: This part is a unique number that is bundled to the signature for tracking ad extra identification reasons.<br />
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6.Digital signature of the CA (certification Authority): This is a signature that is issued by the authority that issues the certificates.<br />
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<b>Signatures and the Law:</b><br />
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A signature is not part of the substance of a transaction, but rather of its representation or form.<br />
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<b>Signing writings serve the following general purposes: </b><br />
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•Evidence: A signature authenticates a writing by identifying the signer with the signed document. When the signer makes a mark in a distinctive manner, the writing becomes attributable to the signer.<br />
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•Ceremony: The act of signing a document calls to the signer's attention the legal significance of the signer's act, and thereby helps prevent "inconsiderate engagements.<br />
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•Approval: In certain contexts defined by law or custom, a signature expresses the signer's approval or authorization of the writing, or the signer's intention that it have legal effect.<br />
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•Efficiency and logistics: A signature on a written document often imparts a sense of clarity and finality to the transaction and may lessen the subsequent need to inquire beyond the face of a document. Negotiable instruments, for example, rely upon formal requirements, including a signature, for their ability to change hands with ease, rapidity, and minimal interruption.<br />
The formal requirements for legal transactions, including the need for signatures, vary in different legal systems, and also vary with the passage of time.<br />
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There is also variance in the legal consequences of failure to cast the transaction in a required form. The statute of frauds of the common law tradition, for example, does not render a transaction invalid for lack of a "writing signed by the party to be charged," but rather makes it unenforceable in court, a distinction which has caused the practical application of the statute to be greatly limited in case law.<br />
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<b>DIGITAL SIGNATURE WORKS ON THE FOLLOWING PROCESS:</b><br />
1)A Singing algorithm<br />
2)A key generation algorithm<br />
3)A verification algorithm<br />
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<b>METHODS TO CREATE DIGITAL SIGNATURE:</b><br />
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<b>MEHTOD 1:</b><br />
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Digital signatures are created and verified by cryptography, the branch of applied mathematics that concerns itself with transforming messages into seemingly unintelligible forms and back again. Digital signatures use what is known as "public key cryptography," which employs an algorithm using two different but mathematically related "keys;" one for creating a digital signature or transforming data into a seemingly unintelligible form, and another key for verifying a digital signature or returning the message to its original form. <br />
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Computer equipment and software utilizing two such keys are often collectively termed an "asymmetric cryptosystem."<br /><br />
The complementary keys of an asymmetric cryptosystem for digital signatures are arbitrarily termed the private key, which is known only to the signer and used to create the digital signature, and the public key, which is ordinarily more widely known and is used by a relying party to verify the digital signature. If many people need to verify the signer's digital signatures, the public key must be available or distributed to all of them, perhaps by publication in an on-line repository or directory where it is easily accessible.<br />
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Although the keys  of the pair are mathematically related, if the asymmetric cryptosystem has been designed and implemented securely it is "computationally infeasible  to derive the private key from knowledge of the public key. Thus, although many people may know the public key of a given signer and use it to verify that signer's signatures, they cannot discover that signer's private key and use it to forge digital signatures. This is sometimes referred to as the principle of "irreversibility."<br />
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<b>METHOD 2:</b><br />
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Another fundamental process, termed a "hash function," is used in both creating and verifying a digital signature. A hash function is an algorithm which creates a digital representation or "fingerprint" in the form of a "hash value" or "hash result" of a standard length which is usually much smaller than the message but nevertheless substantially unique to it. <br />
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Any change to the message invariably produces a different hash result when the same hash function is used. In the case of a secure hash function, sometimes termed a "one-way hash function," it is computationally infeasible  to derive the original message from knowledge of its hash value. Hash functions therefore enable the software for creating digital signatures to operate on smaller and predictable amounts of data, while still providing robust evidentiary correlation to the original message content, thereby efficiently providing assurance that there has been no modification of the message since it was digitally signed.<br />
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Thus, use of digital signatures usually involves two processes, one performed by the signer and the other by the receiver of the digital signature:<br />
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•Digital signature creation uses a hash result derived from and unique to both the signed message and a given private key. For the hash result to be secure, there must be only a negligible possibility that the same digital signature could be created by the combination of any other message or private key.<br />
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•Digital signature verification is the process of checking the digital signature by reference to the original message and a given public key, thereby determining whether the digital signature was created for that same message using the private key that corresponds to the referenced public key.<br />
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<b>The creation of a digital signature</b><br />
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In the simplest terms a digital signature is a stream of bits appended to a document. The purpose of a digital signature is to provide assurance about the origin of the message and the integrity of the message contents. When a message with a digital signature is transmitted and received, the following parties are involved:<br />
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•<span class="Apple-tab-span" style="white-space: pre;"> </span>the signer who signs the document;<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>the verifier who receives the signed document and verifies the signature ;<br />
•<span class="Apple-tab-span" style="white-space: pre;"> </span>the arbitrator who arbitrates any disputes between the signer and the verifier if there is a disagreement on the validity of the digital signature.<br />
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Digitally signing a document begins with producing a summary of the document using mathematical functions known as hash functions. Some examples are Message Digest-5 (MD5), Secure Hash Algorithm-1 (SHA-1) and Réseaux IP Européens (RIPE) Message Digest-160 (RIPMED-160). The output of a hash function, a document summary called the hash, always has the same number of bits<br />
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e.g. 128 for MD5 and 160 for SHA-1, regardless of the length of the input document. It is obvious that different documents will produce different hashes. It is considered virtually impossible to have an identical hash even from two similar documents.<br />
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The hash function is encrypted by the signer using his/her private key and forms the digital signature of the encrypted document.<br />
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The verifier receives both the document and the signature, calculates the summary of the document using the same hash function used by the signer. The signature is decrypted using the signer’s public key. The last step is to compare the decrypted summary with the one previously computed by the verifier from the document. If the two summaries are identical then the signature has been verified. The verifier is now sure of the identity of the signer and that the data was not been modified.<br />
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DIGITAL SIGNATURE

INTRODUCTION: In today's commercial environment, establishing a framework for the authentication of computer-based information requires a familiarity with concepts and professional skills from both the legal and computer security fields. Combining these two disciplines is not an easy task. Concept…

25Apr2015

DATA MINING

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<b>INTRODUCTION:</b><br />
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Data mining, the extraction of hidden predictive information from large databases, is a powerful new technology with great potential to help companies focus on the most important information in their data warehouses. Data mining tools predict future trends and behaviors, allowing businesses to make proactive, knowledge-driven decisions. The automated, prospective analyses offered by data mining move beyond the analyses of past events provided by retrospective tools typical of decision support systems. Data mining tools can answer business questions that traditionally were too time consuming to resolve. They scour databases for hidden patterns, finding predictive information that experts may miss because it lies outside their expectations.<br />
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Most companies already collect and refine massive quantities of data. Data mining techniques can be implemented rapidly on existing software and hardware platforms to enhance the value of existing information resources, and can be integrated with new products and systems as they are brought on-line. When implemented on high performance client/server or parallel processing computers, data mining tools can analyze massive databases to deliver answers to questions such as, "Which clients are most likely to respond to my next promotional mailing, and why?"<br />
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This white paper provides an introduction to the basic technologies of data mining. Examples of profitable applications illustrate its relevance to today’s business environment as well as a basic description of how data warehouse architectures can evolve to deliver the value of data mining to end users.<br />
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<b>The Foundations of Data Mining:</b></div>
<div>
<b><br /></b></div>
<div>
<div>
Data mining techniques are the result of a long process of research and product development. This evolution began when business data was first stored on computers, continued with improvements in data access, and more recently, generated technologies that allow users to navigate through their data in real time. Data mining takes this evolutionary process beyond retrospective data access and navigation to prospective and proactive information delivery. Data mining is ready for application in the business community because it is supported by three technologies that are now sufficiently mature: </div>
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<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Massive data collection </div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Powerful multiprocessor computers </div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Data mining algorithms </div>
<div>
<br /></div>
<div>
Commercial databases are growing at unprecedented rates. A recent META Group survey of data warehouse projects found that 19% of respondents are beyond the 50 gigabyte level, while 59% expect to be there by second quarter of 1996.1 In some industries, such as retail, these numbers can be much larger. The accompanying need for improved computational engines can now be met in a cost-effective manner with parallel multiprocessor computer technology. </div>
<div>
<br /></div>
<div>
Data mining algorithms embody techniques that have existed for at least 10 years, but have only recently been implemented as mature, reliable, understandable tools that consistently outperform older statistical methods.</div>
<div>
<br /></div>
<div>
In the evolution from business data to business information, each new step has built upon the previous one. For example, dynamic data access is critical for drill-through in data navigation applications, and the ability to store large databases is critical to data mining. From the user’s point of view, the four steps listed in Table 1 were revolutionary because </div>
<div>
they allowed new business questions to be answered accurately and quickly. </div>
<div>
<br /></div>
<div>
The core components of data mining technology have been under development for decades, in research areas such as statistics, artificial intelligence, and machine learning. </div>
<div>
<br /></div>
<div>
Today, the maturity of these techniques, coupled with high-performance relational database engines and broad data integration efforts, make these technologies practical for current data warehouse environments</div>
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<br /></div>
</div>
<div>
<b>The Scope of Data Mining:</b></div>
<div>
<br /></div>
<div>
<div>
Data mining derives its name from the similarities between searching for valuable business information in a large database — for example, finding linked products in gigabytes of store scanner data — and mining a mountain for a vein of valuable ore. Both processes require either sifting through an immense amount of material, or intelligently probing it to find exactly where the value resides. Given databases of sufficient size and quality, data mining technology can generate new business opportunities by providing these capabilities: </div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Automated prediction of trends and behaviors. Data mining automates the process of finding predictive information in large databases. Questions that traditionally required extensive hands-on analysis can now be answered directly from the data — quickly. A typical example of a predictive problem is targeted marketing. Data mining uses data on past promotional mailings to identify the targets most likely to maximize return on investment in future mailings. Other predictive problems include forecasting bankruptcy and other forms of default, and identifying segments of a population likely to respond similarly to given events. </div>
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<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Automated discovery of previously unknown patterns. Data mining tools sweep through databases and identify previously hidden patterns in one step. </div>
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<br /></div>
<div>
An example of pattern discovery is the analysis of retail sales data to identify seemingly unrelated products that are often purchased together. Other pattern discovery problems include detecting fraudulent credit card transactions and identifying anomalous data that could represent data entry keying errors. </div>
<div>
<br /></div>
<div>
Data mining techniques can yield the benefits of automation on existing software and hardware platforms, and can be implemented on new systems, as existing platforms are upgraded and new products developed. When data mining tools are implemented on high performance parallel processing systems, they can analyze massive databases in minutes. Faster processing means that users can automatically experiment with more models to understand complex data. High speed makes it practical for users to analyze huge quantities of data. Larger databases, in turn, yield improved predictions. </div>
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<br /></div>
<div>
<b>Databases can be larger in both depth and breadth: </b></div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>More columns. Analysts must often limit the number of variables they examine when doing hands-on analysis due to time constraints. Yet variables that are discarded because they seem unimportant may carry information about unknown patterns. High performance data mining allows users to explore the full depth of a database, without preselecting a subset of variables. </div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>More rows. Larger samples yield lower estimation errors and variance, and allow users to make inferences about small but important segments of a population. </div>
<div>
A recent Gartner Group Advanced Technology Research Note listed data mining and artificial intelligence at the top of the five key technology areas that "will clearly have a major impact across a wide range of industries within the next 3 to 5 years."2 Gartner also listed parallel architectures and data mining as two of the top 10 new technologies in which companies will invest during the next 5 years. According to a recent Gartner HPC Research Note, "With the rapid advance in data capture, transmission and storage, large-systems users will increasingly need to implement new and innovative ways to mine the after-market value of their vast stores of detail data, employing MPP [massively parallel processing] systems to create new sources of business advantage (0.9 probability)."3 </div>
<div>
<br /></div>
<div>
<b>The most commonly used techniques in data mining are: </b></div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Artificial neural networks: Non-linear predictive models that learn through training and resemble biological neural networks in structure. </div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Decision trees: Tree-shaped structures that represent sets of decisions. These decisions generate rules for the classification of a dataset. Specific decision tree methods include Classification and Regression Trees (CART) and Chi Square Automatic Interaction Detection (CHAID). </div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Genetic algorithms: Optimization techniques that use processes such as genetic combination, mutation, and natural selection in a design based on the concepts of evolution. </div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Nearest neighbor method: A technique that classifies each record in a dataset based on a combination of the classes of the k record(s) most similar to it in a historical dataset (where k ³ 1). Sometimes called the k-nearest neighbor technique. </div>
<div>
<br /></div>
<div>
<span class="Apple-tab-span" style="white-space: pre;"> </span>Rule induction: The extraction of useful if-then rules from data based on statistical significance. </div>
<div>
Many of these technologies have been in use for more than a decade in specialized analysis tools that work with relatively small volumes of data. These capabilities are now evolving to integrate directly with industry-standard data warehouse and OLAP platforms</div>
<div>
<br /></div>
<div>
<b>How Data Mining Works:</b></div>
<div>
<br /></div>
<div>
How exactly is data mining able to tell you important things that you didn't know or what is going to happen next? The technique that is used to perform these feats in data mining is called modeling. Modeling is simply the act of building a model in one situation where you know the answer and then applying it to another situation that you don't. </div>
<div>
<br /></div>
<div>
For instance, if you were looking for a sunken Spanish galleon on the high seas the first thing you might do is to research the times when Spanish treasure had been found by others in the past. You might note that these ships often tend to be found off the coast of Bermuda and that there are certain characteristics to the ocean currents, and certain routes that have likely been taken by the ship’s captains in that era. </div>
<div>
<br /></div>
<div>
You note these similarities and build a model that includes the characteristics that are common to the locations of these sunken treasures. With these models in hand you sail off looking for treasure where your model indicates it most likely might be given a similar situation in the past. Hopefully, if you've got a good model, you find your treasure.</div>
<div>
<br /></div>
<div>
This act of model building is thus something that people have been doing for a long time, certainly before the advent of computers or data mining technology. What happens on computers, however, is not much different than the way people build models. </div>
<div>
<br /></div>
<div>
Computers are loaded up with lots of information about a variety of situations where an answer is known and then the data mining software on the computer must run through that data and distill the characteristics of the data that should go into the model. Once the model is built it can then be used in similar situations where you don't know the answer. </div>
<div>
<br /></div>
<div>
For example, say that you are the director of marketing for a telecommunications company and you'd like to acquire some new long distance phone customers. You could just randomly go out and mail coupons to the general population - just as you could randomly sail the seas looking for sunken treasure. In neither case would you achieve the results you desired and of course you have the opportunity to do much better than random - you could use your business experience stored in your database to build a model.</div>
<div>
<br /></div>
<div>
As the marketing director you have access to a lot of information about all of your customers: their age, sex, credit history and long distance calling usage. The good news is that you also have a lot of information about your prospective customers: their age, sex, credit history etc. Your problem is that you don't know the long distance calling usage of these prospects (since they are most likely now customers of your competition). </div>
<div>
<br /></div>
<div>
You'd like to concentrate on those prospects who have large amounts of long distance usage. You can accomplish this by building a model. Table 2 illustrates the data used for building a model for new customer prospecting in a data warehouse.</div>
<div>
<br /></div>
</div>
</div>

DATA MINING

INTRODUCTION: Data mining, the extraction of hidden predictive information from large databases, is a powerful new technology with great potential to help companies focus on the most important information in their data warehouses. Data mining tools predict future trends and behaviors, allowing busi…

25Apr2015

Cyborg

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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">In the years ahead we
will witness machines with intelligence more powerful than that of humans. This
will mean that robots, not humans, make all the important decisions. It will be
a robot-dominated world with dire consequences for humankind. Is there an alternative
way ahead?<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;"><br />
Humans have limited capabilities. Humans sense the world in a restricted way,
vision being the best of the senses. Humans understand the world in only 3
dimensions and communicate in a very slow, serial fashion called speech. But
can this be improved on? Can we use technology to upgrade humans?<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;"><br />
The possibility exists to enhance human capabilities. To harness the
ever-increasing abilities of machine intelligence, to enable extra sensory
input and to communicate in a much richer way, using thought alone. Kevin
Warwick has taken the first steps on this path, using himself as a guinea pig
test subject receiving, by surgical operation, technological implants connected
to his central nervous system.<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;"><br />
A Cyborg is a Cybernetic Organism, part human part machine. In this we will go
through Kevin Warwick’s amazing steps towards becoming a Cyborg. The story is
one of scientific endeavour and devotion, splitting apart the personal lives of
himself and those around him. This astounding and unique story takes in top
scientists from around the globe and seriously questions human morals, values
and ethics.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">Now question is, Will
the thought of Cyborg is in favor of Human in the future? What will happen when
man is merged with a computer? There are many questions, but a proper and good
approach towards Cyborg will be beneficial for Humans. Because it is individual
choice for any human that whether he wants extra capabilities by implant
technology and become Cyborg or whether he just want to be mere a man only.
Because electronic tagging can be regarded as a more permanent form of
identification than a smart card. An implant could carry huge amounts of data
on an individual, such as National Insurance number and blood type, blood
pressure etc. allowing information to be communicated to on-line doctors over
the internet. Thus Depending on how the technology is used, there are good and
bad effects. So much of this smacks of the Big Brother. With an implant, a
machine will know where an individual is, in a building, ...... at all times.
You might not even be able to pay a visit to the toilet without a machine knowing
about it. <o:p></o:p></span></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 12pt;">CYBORG:</span></b><span style="font-family: 'Times New Roman', serif; font-size: 12pt;"><o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">            <o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">CYBORG, a compound word
derived from cybernetics and organism, is a term coined by Manfred Clynes in
1960 to describe the need for mankind to artificially enhance biological
functions in order to survive in the hostile environment of Space. Originally,
a CYBORG referred to a “Human being with bodily functions aided or controlled
by technological devices, such as an oxygen tank, artificial heart valve or
insulin pump”. Over the years, the term has acquired a more general meaning, describing
the dependence of human beings on technology. In this sense, CYBORG can be used
to characterize anyone who relies on a computer to complete his or her daily
work..<o:p></o:p></span></div>
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<br /></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 12pt;">WHAT IS CYBORG? <o:p></o:p></span></b></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">A CYBORG is a Cybernetic
Organism, part human part machine. This concept is bit tricky but let see an
example of a CYBORG, You may have seen the movie TERMINATOR. In that ARNOLD was
a CYBORG. He was part man part machine. Well defination exactly says this,
CYBORG can be made by technology known as CYBERNETICS. What is CYBERNETICS? To
understand CYBORG this is the first step next we will see this.<o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 12pt;">WHAT IS
CYBERNETICS? </span></b><span style="font-family: 'Times New Roman', serif; font-size: 12pt;"><o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">Cybernetics is a word
coined by group of scientists led by Norbert Wiener and made popular by
Wiener's book of 1948, Cybernetics or Control and Communication in the Animal
and the Machine. Based on the Greek "kybernetes," meaning steersman
or governor, cybernetics is the science or study of control or regulation
mechanisms in human and machine systems, including computers. <o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">CYBERNETICS could be thought
of as a recently developed science, although to some extent it cuts across
existing sciences. If we think of Physics, Chemistry, Biology, etc. as
traditional sciences, then Cybernetics is a classification, which cuts across
them all. ...Cybernetics is formally defined as the science of control and
communication in animals, men and machines. It extracts, from whatever context,
that which is concerned with information processing and control. ... One major
characteristic of Cybernetics is its preoccupation with the construction of
models and here it overlaps operational research. Cybernetic models are usually
distinguished by being hierarchical, adaptive and making permanent use of
feedback loops. ... Cybernetics in some ways is like the science of organization,
with special emphasis on the dynamic nature of the system being
organized."<o:p></o:p></span></div>
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Cyborg

In the years ahead we will witness machines with intelligence more powerful than that of humans. This will mean that robots, not humans, make all the important decisions. It will be a robot-dominated world with dire consequences for humankind. Is there an alternative way ahead? Humans have limited …

25Apr2015

What is Cryptography?

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The requirement
of <b>information security</b> within an
organization has under gone two major changes in the last several decades.
Before the widespread use of data processing equipment, the security of
information felt to be valuable to an organization was provided primarily by
physical and administrative means. An example of the former is the use of rugged
filing cabinets with a combination lock for storing sensitive documents. An
example of the latter is personnel screening procedures used during the hiring
process.</div>
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<span style="text-indent: 0.5in;">With the
introduction of computer, the need for automated tools for protecting files and
other information stored on the computer became evident. This is especially the
case for a shared system, such as a time-sharing system, and the need is even
more acute for system that can be accessed over public telephone network, data
network, or the Internet. The generic name for the collection of the tools
designed to protect data and to thwart hackers is </span><b style="text-indent: 0.5in;">computer security.</b></div>
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            </div>
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The second major
change that affected security is the introduction of distributed system and the
use of network and communication facilities for carrying data between terminal
user and computer and between computer and computer. Network security measure
are needed to protect data during their transmission. In fact, the term <b>network security </b>is somewhat
misleading,<b> </b>because virtually all
business, government, and academic organization interconnect their data
processing equipment with a collection of interconnected networks. Such a
collection is often referred to as an internet, and the term <b>internet security </b>is used.    <b>  </b></div>
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            </div>
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There are no
clear boundaries between these two forms of security. For example, one of the
most publicized types of attack on information system is the computer virus. A
virus may be introduced into a system physically when it arrives on a diskette
and is subsequently loaded onto a computer. Viruses may also arrive over an
internet. In either case, once the virus is resident on a computer security
tools are needed to detect and recover from the virus</div>
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<br /></div>
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<br /></div>
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            <b>Cryptography</b> is the study of
mathematical techniques related to aspects of information security, such as
confidentially or privacy ,data integrity and entity authentication.
Cryptography is not only means of providing information security, but rather
one set of techniques. Confidentially means keeping information secret from all
but those who authorized to see it. Data integrity means ensuring information
has not been altered by unauthorized or unknown means. Entity authentication
means corroboration of the identify of an entity.</div>
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            There
are some <b>characteristics</b> of
cryptographic algorithm. They are level security, performance , and ease of
implementation. Level security defined by an upper bound on the among of work
necessary to defeat the objective. Performance refers to the efficiency of an
algorithm in a particular mode of an operation. Ease of implementation refers
to the difficulty of realizing the algorithm in practical implementation.</div>
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</div>
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There are
several <b>aspects </b>of security. They
are security service, security mechanism, and security attack. Security service
means a service that enhances the security of the data processing system and
information transfers of an organization.      
Security mechanism means that is designed to detect, prevent, or recover
from a security attacks. Security attack means any action that compromises the
security of information owned by an organization. </div>
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<b>Encryption </b> means the process of converting from plaintext
to ciphertext. A key is a piece of information , usually a number that allows a
receiver. Another key also allows a receiver to decode messages sent to him or
her. There are some types of encryption. They are classical techniques, modern
techniques, and public-key encryption. In Classical techniques there are
substitution techniques and transposition techniques. In substitution
techniques there are Caesar cipher, monoalphabetic cipher and polyalphabetic
cipher. In Modern techniques there are block cipher , stream cipher and DES
algorithm. In Public-key encryption the RSA algorithm is there.</div>
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            Cryptography
has provided us with <b>Digital Signatures</b>
that resemble in functionality the hand-written signature and <b>Digital Certificates</b> that related to an
ID -card or some other official documents. There are some <b>application</b> of cryptography. They are secure communication,
identification, secret sharing, electronic commerce, key recovery and remote
access. </div>
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 Modern cryptography provides essential
techniques for securing information and protecting data.                    </div>
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</div>

What is Cryptography?

The requirement of information security within an organization has under gone two major changes in the last several decades. Before the widespread use of data processing equipment, the security of information felt to be valuable to an organization was provided primarily by physical and administrati…

25Apr2015

Clock less Chips

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<b>INTRODUCTION:</b></h3>
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In
labs at Sun Microsystems, Intel and IBM, clock less chips have increased the
pace at which high-end processors do their work. In 1997, Intel developed an
asynchronous, Pentium-compatible test chip that ran three times as fast, on
half the power, as its synchronous equivalent. <o:p></o:p></div>
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 Fant has focused on still another benefit of
asynchronous design. Because these chips give off no regularly timed signal,
the way clocked circuits do, they can perform encryption in a way that is
harder to identify and to crack. Improved encryption makes asynchronous
circuits an obvious choice for smart cards—the chip-endowed plastic cards
beginning to be used for such security-sensitive applications as storage of
medical records, electronic funds exchange and personal identification. . <o:p></o:p></div>
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SMT offers chip designers a big performance
gain for a relatively small design change; asynchronous logic involves a far
more dramatic rethink. As its name suggests, it does away with the cardinal
rule of chip design: that everything marches to the beat of an oscillating
crystal “clock”. For a 1GHz chip, this clock ticks one billion times a second,
and the entire chip’s processing unit’s co-ordinate their actions with these
ticks to ensure that they remain in step. Asynchronous, or “clock less”,
designs, in contrast, allow different bits of a chip to work at different
speeds, sending data to and from each other as and when appropriate.<o:p></o:p></div>
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In recent years,
however, clock less designs have started to look more appealing. One reason is
that, as chips get bigger, faster and more complicated, distributing the clock
signal around the chip becomes harder. Another drawback with clocked designs is
that they waste a lot of energy, since even inactive parts of the chip have to
respond to every clock tick. Clocked chips also produce electromagnetic
emissions at their clock frequency, which can cause radio interference.<o:p></o:p></div>
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Asynchronous
designs take up more room on a chip than conventional designs, and there are
far fewer design tools available to help create them,  It is believes that such chips will have twice
the power of conventional designs, which will make them ideal for use in
high-performance computers. The most promising application for asynchronous
chips may be in mobile wireless devices and smartcards.<o:p></o:p></div>
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One
of the advantages of clock less chips is that they give off very low levels of
electromagnetic noise. The faster the clock, the more difficult it is to
prevent a device from interfering with other devices; dispensing with the clock
all but eliminates this problem. The combination of low noise and low power
consumption makes asynchronous chips a natural choice for mobile devices.
"The low-hanging fruit for clock less chips will be in communications
devices," starting with cell phones. <o:p></o:p></div>
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Wireless devices
based on asynchronous chips would run for longer between recharges, and their
circuitry would cause less radio interference. Dr Furber is developing
asynchronous chips for such devices in conjunction with ARM, a British company
whose processors appear in many handheld computers and mobile phones. Philips,
a Dutch electronics firm, has already built a pager that uses asynchronous
logic, and Theseus Logic of Orlando, Florida, is also pursuing low-power
wireless applications.<o:p></o:p></div>
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<br /></div>
<span style="font-family: 'Times New Roman', serif; font-size: 12pt;">In the case of smartcards, Dr Furber suggests
that asynchronous logic would offer better security than conventional chips.
The encryption on existing smartcards can be cracked by analyzing the power
consumption for each clock tick. This allows details of the chip’s inner
workings to be deduced. Such an attack would be far more difficult on a
smartcard based on asynchronous logic.        </span><br />
<span style="font-family: 'Times New Roman', serif; font-size: 12pt;"><br /></span>
<h3 style="text-align: left;">
<span style="font-family: Times New Roman, serif;"><b>CLOCKLESS CHIPS:</b></span></h3>
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There are no purely
asynchronous chips yet. Instead, today’s clock less processors are actually
clocked processors with asynchronous elements. Clock less elements use <i>perfect
clock gating</i>, in which circuits operate only when they have work to do, not
whenever a clock ticks. Instead of clock-based synchronization, local
handshaking controls the passing of data between logic modules. The
asynchronous processor places the location of the stored data it wants to read
onto the address bus and issues a request for the information. The memory reads
the address off the bus, finds the information, and places it on the data bus.
The memory then acknowledges that it has read the data. Finally, the processor
grabs the information from the data bus. Pipeline controls and FIFO sequencers
move data and instructions around and keep them in the right order. According
to Jorgenson, “Data arrives at any rate and leaves at any rate. When the
arrival rate exceeds the departure rate, the circuit stalls the input until the
output catches up.” The many handshakes themselves require more power than a
clock’s operations. However, clock less systems more than offset this because,
unlike synchronous chips, each circuit uses power only when it performs work.</div>
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<br /></div>
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<span style="font-family: Garamond, serif;"><span style="font-size: 18.6666660308838px;"><b>CLOCK LESS ARM996HS</b></span></span></div>
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<span style="background-color: white; line-height: 150%; text-align: justify;">The compact, clock less ARM996HS processor is an ideal
solution for automotive, medical and deeply embedded control applications
because of its extremely low power consumption and low Electro Magnetic
Interference (EMI). The ARM996HS processor is the industry’s first licensable clock
less processor and directly addresses the needs of design engineers for
technology optimized for robust and real-time chip designs.</span></div>
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The ARM996HS processor utilizes Handshake Solutions’
technology, a production-proven methodology for implementing self-timed
circuitry which has been used in hundreds of millions of chips for smart cards,
advanced pagers, in-vehicle network transceivers, and cordless handsets. By
leveraging this low EME technology, the ARM996HS processor can address the
market need for very low EMI to reduce packaging and shielding costs.
Additionally, the processor can be used in applications that require low
current consumption and an extended battery life while maintaining real-time
application responsiveness and a small footprint. <o:p></o:p></div>
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<br /></div>
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By removing the clock and associated architecture of
standard ICs, clock less designs offer significant reductions in power consumption
and EMI enabling designers to squeeze more functionality into limited power
budgets. Handshake Solutions offers an extremely disciplined design methodology
that delivers the unique benefits of clock less design within a commercially
available design environment. The methodology is supported by easy-to-use and
thoroughly field-tested tools, design services, and standard IP blocks from
Handshake Solutions<o:p></o:p></div>
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<span lang="EN">The new ARM996HS processor is
optimized for use in both synchronous (clocked) and asynchronous (clock less)
system-on-chip designs, enabling easy integration by ARM semiconductor
Partners. Engineers can easily design in the new processor using<b> </b>standard cell libraries such as the
ARM Metro family for low power, and their existing EDA tools, for lower costs
and shorter design cycles. The key benefits of the processor include low EMI,
reducing the probability of interfering with sensitive circuitry; low current
peaks, enabling easier integration with analog components; and low power
consumption, reducing system power requirements. Because clock less processors
consume zero dynamic power when there is no activity, they can significantly
extend battery life<o:p></o:p></span></div>
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<span lang="EN" style="font-family: Garamond, serif; font-size: 14pt; line-height: 150%;"><b>FUNCTIONING<o:p></o:p></b></span></div>
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<br /></div>
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Clock less logic
uses a system of local handshaking rather than a global clock to define
transaction timing. Handshakes are implemented by means of simple request and
acknowledge signals that mark the validity of the data. This approach means
that only those parts of a system actively involved in task execution draw
power, reducing active standby power consumption to zero and extending battery
lifetimes. Execution of individual functions need not wait for the next clock
pulse, enabling immediate response to exceptional events.  Wake-up from interrupt can even be performed
without a running clock. Handshake Solutions’ clock less designs supports
integration with synchronous blocks and systems. This means that the clock less
ARM996HS processor can be easily integrated into a conventional, clocked SoC
design. Because they exhibit no ground bounce, Handshake Solutions functions
can be quickly and easily combined with clocked logic, analog, RF or memory
blocks to meet the exact system requirements.</div>
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<br /></div>
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<b><span style="font-size: 14.0pt; line-height: 150%;">A COMPLETE CLOCK LESS DESIGN SOLUTION<o:p></o:p></span></b></div>
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<br /></div>
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Although the
theoretical principles of clock less design are well-defined, implementation of
clock less logic within the context of a complex system design has not,
historically, been straightforward. Potential issues included the availability
of design flow support, the need for special clock less standard-cell
libraries, the area overhead arising from the control logic necessary to
implement the self-timing, and ensuring that clock less designs are testable
using industry-supported techniques.</div>
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<br /></div>
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Handshake
Solutions has brought clock less technology to a level of maturity where the
technology has now been proven on many designs. With dozens of production
designs incorporating Handshake Technology successfully complete, over a
hundred million Handshake Technology-based ICs have been manufactured, tested
and sold. Developing a rigorous approach has solved the problems that have been
experienced in the practical application of asynchronous technologies in the
past.  </div>
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<br /></div>
<span style="line-height: 150%; text-align: justify;">Handshake
Solutions’ offering includes a design flow based on standard cell libraries
with no dedicated asynchronous cells required. The flow is compatible with
standard ‘synchronous’ tools for technology mapping, logic optimization, timing
analysis and testing.</span><span style="line-height: 150%; text-align: justify;">  </span><span style="line-height: 150%; text-align: justify;">A high-level
design entry language called Haste (formerly Tangram), developed specifically
for the specification and designs of clock less circuit, provides the entry
mechanism. Haste, being similar to C and behavioral Verilog, is easy to learn
and use. The design description is synthesized using Handshake Solutions’
silicon compiler. </span><br />
<span style="line-height: 150%; text-align: justify;"><br /></span>
<span style="line-height: 150%; text-align: justify;">Once the Verilog netlist has been generated, the back-end
design to GDSII can follow any industry-standard implementation flow. This
means that for licensees of the ARM996HS who wish to integrate the processor
into their SoC, it is not necessary to adopt the full Handshake Solutions
design flow, but simply take the Verilog netlist and incorporate it as an IP
block. The methodology also supports scan-test for complete design for test
(DFT) solutions, ensuring that design teams can make use of standard automatic test
pattern generation (ATPG) techniques</span><span style="font-family: 'Times New Roman', serif; font-size: 12pt;"><b> </b>          </span><br />
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The ARM996HS is a new 32-bit RISC processor core –
part of the ARM9E family of cores. The ARM9E family is based on the ARMv5TE
Instruction Set Architecture (ISA), which includes the 16-bit Thumb® and 32-bit
ARM instruction sets. The Harvard-architecture core is based on a 5-stage
integer pipeline with fast 32-bit multiply-accumulate (MAC) block. It has
tightly coupled memories (TCMs) for both instruction and data, each of which
can be up to 4MB. Dual AMBA™ AHB-Lite™ synchronous buses provide the
instruction and data interfaces. Specific security enhancements for the
ARM996HS core include a memory protection unit (MPU) and the provision of
non-maskable interrupts (NMI). A hardware divide co-processor is also provided.</div>
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<b><span style="font-size: 14.0pt;">CLOCK LESS PIPELINE<o:p></o:p></span></b></div>
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The pipeline within the ARM996HS core mirrors the
normal ARMv5TE pipeline, with the exception that it is implemented as a clock
less design. Instead of a global synchronous clock, dedicated control logic
ensures that each stage in the pipeline is enabled only when required. The
pipeline handshakes with the system controller to fetch instructions and to
load and store data.</div>
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<b><span style="font-size: 14.0pt;">ENHANCED MEMORY PROTECTION UNIT<o:p></o:p></span></b></div>
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In order to enable software re-use from several
different sources, it is vital that there is a mechanism to allow each module
to be isolated so that the risk of interference is minimized. The requirement
is to be able to isolate or ‘lock down’ many of these routines. This is
performed by the memory protection unit (MPU). Current Memory Protection Units
(MPUs) typically offer 4KByte code boundaries for isolating functions. This is
typically too large for systems which have limited memory resources. Large code
boundaries mean that it is impossible to efficiently segregate many small
software routines – often several tasks will have to be included within the same
protection scheme.</div>
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To enable good segregation of individual tasks
executed within an operating system (OS) kernel, the ARM996HS MPU provides a
fine 32-byte granularity of memory region for each task. This enables more
effective use of the available memory resource for supporting multiple tasks.
With this level of granularity it is possible to separate: User from system,
task from task, data from data and stack from stack.Shared access is possible
via overlapping regions.</div>
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<br /></div>
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<b><span style="font-size: 14.0pt; line-height: 150%;">NON-MASKABLE
INTERRUPTS<o:p></o:p></span></b></div>
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<br /></div>
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Non-Maskable Interrupts (NMI) enables fast interrupt
requests to be made nonmaskable</div>
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by software. Where predictability of execution is
especially important, such as with control applications, NMI is a mandatory
requirement. NMI is particularly important when a watchdog is used in the
system that needs to be serviced at a particular time.</div>
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<b><span style="font-size: 14.0pt; line-height: 150%;">HARDWARE
DIVIDE COPROCESSOR<o:p></o:p></span></b></div>
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For applications where there is a requirement to
scale values read from sensors, the hardware divide instruction enables data to
be manipulated very efficiently. The hardware divide coprocessor provides
efficient implementation of division operations in parallel to the main
processor pipeline. It supports unsigned and signed 32-bit division through
normal coprocessor instructions. The hardware divide coprocessor is easy for
developers to use with tools and library support provided.</div>
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<span style="line-height: 24px;"><b>ADVANTAGES:</b></span></div>
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<span style="line-height: 24px;"><b><br /></b></span></div>
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<span style="line-height: 150%;">Difficulties associated with traditional synchronous design
have prompted many researchers to consider new alternatives. Three factors
drive current research and development efforts in the design and test of clock
less digital systems:</span></div>
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A) Low power</div>
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B) Performance</div>
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C) Design for reuse.</div>
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<br /></div>
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<b><span style="font-size: 14.0pt; line-height: 150%;">LOW POWER<o:p></o:p></span></b></div>
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<br /></div>
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The mainstream design style in use for today’s processors
is synchronous, that is, a clock regulates the internal timing. We measure how
fast a computer can execute instructions by the number of clock cycles per second.
Unfortunately, the clock consumes more power than most other components in the
chip. The most disturbing aspect of this characteristic is that the clock only serves
as a timer for computational tasks. It does not perform operations on data, it
simply orchestrates the many computational parts of a digital system (whether
chip, board, or computer). New problems are also evident for power consumption at-large;
that is, throughout the system in general. As the number of transistors on a
chip increases, so does the power used by the clock. Therefore, in complicated chips,
power consumption becomes an even more crucial topic. For mobile and portable
electronics, chips must conserve power even more efficiently to maximize
battery life. Low-power design is important </div>
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<br /></div>
</div>

Clock less Chips

INTRODUCTION: In labs at Sun Microsystems, Intel and IBM, clock less chips have increased the pace at which high-end processors do their work. In 1997, Intel developed an asynchronous, Pentium-compatible test chip that ran three times as fast, on half the power, as its synchronous equivalent. Fan…

25Apr2015

CDMA(Code Division Multiple Access)

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The world is demanding more from wireless communication technologies than ever before. More people around the world are subscribing to wireless services and consumers are using their phones more frequently. Add in exciting Third-Generation (3G) wireless data services and applications - such as wireless email, web, digital picture taking/sending and assisted-GPS position location applications - and wireless networks are asked to do much more than just a few years ago. And these networks will be asked to do more tomorrow.<br />
<br />
This is where CDMA technology fits in. CDMA consistently provides better capacity for voice and data communications than other commercial mobile technologies, allowing more subscribers to connect at any given time, and it is the common platform on which 3G technologies are built.<br />
<br />
CDMA permits a more uniform distribution of energy in the emitted bandwidth Short for Code Division Multiple Access, a digital cellular technology that uses spread-spectrum techniques. Unlike competing systems, such as GSM that use TDMA, CDMA does not assign a specific frequency to each user. Instead, every channel uses the full available spectrum. Individual conversations are encoded with a pseudo-random digital sequence.<br />
<br />
CDMA is a "spread spectrum" technology, allowing many users to occupy the same time and frequency allocations in a given band/space. As its name implies, CDMA assigns unique codes to each communication to differentiate it from others in the same spectrum. In a world of finite spectrum resources, CDMA enables many more people to share the airwaves at the same time than do alternative technologies.<br />
<br />
CDMA has greater voice quality and call clarity than other technologies because it filters out background noise, cross-talk and interference. CDMA has fewer dropped calls because it increases voice and date transmission reliability. CDMA has greater spectral efficiency because it packs more transmissions into the same space, resulting in fewer cell sites, which lowers operators' costs. Add to this increased capacity, enhanced privacy, and improved coverage… why would you use any other wireless technology?<br />
<br />
The CDMA air interface is used in both 2G and 3G networks. 2G CDMA standards are branded cdmaOne and include IS-95A and IS-95B. CDMA is the foundation for 3G services: the two dominant IMT-2000 standards, CDMA2000 and WCDMA, are based on CDMA.<br />
<div>
<br /></div>
</div>

CDMA(Code Division Multiple Access)

The world is demanding more from wireless communication technologies than ever before. More people around the world are subscribing to wireless services and consumers are using their phones more frequently. Add in exciting Third-Generation (3G) wireless data services and applications - such as wire…

25Apr2015

What is Bluetooth?

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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">Bluetooth wireless
technology is a de facto standard, as well as a specification for small form
factor, low-cost, short range radio links between mobile PCs, mobile phones and
other portable devices. The Bluetooth Special Interest Group is an industry group
consisting of leaders in the telecommunications, computing, and networking
industries that are driving development of the technology and bringing it to
market.<o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">How did the need arise?</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">In phase with the IT boom, the mobility among people has
constantly grown and wireless technologies for voice and data have evolved
rapidly during the past years. Countless electronic devices for home, personal
and business use have been presented to the market during recent years but no
widespread technology to address the needs of connecting personal devices in
Personal Area Networks (PANs). The demand for a system that could easily
connect devices for transfer of data and voice over short distances without
cables grew stronger.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">Bluetooth wireless technology fills this important communication
need, with its ability to communicate both voice and data wirelessly, using a
standard low-power, low-cost technology which can be integrated in all devices
to enable total mobility. The price will be low and result in mass production.
The more units around, the more benefits for the customer.<o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">Why Bluetooth ?</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">What will Bluetooth
wireless technology deliver to end users?</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">It will enable users to connect a wide range of computing and
telecommunications devices easily and simply, without the need to buy, carry,
or connect cables. It delivers opportunities for rapid ad hoc connections, and
the possibility of automatic, unconscious, connections between devices. It will
virtually eliminate the need to purchase additional or proprietary cabling to
connect individual devices. Because Bluetooth wireless technology can be used
for a variety of purposes, it will also potentially replace multiple cable
connections via a single radio link. It creates the possibility of using mobile
data in a different way, for different applications such as "Surfing on
the sofa", "The instant postcard", "Three in one
phone" and many others. It will allow them to think about what they are
working on, rather than how to make their technology work. The solution
eliminates the annoying cable and its limitations regarding flexibility (often
specific for a brand or pair of devices) and range. But, Bluetooth implies more
than that. The technique provides the means for connecting several units to
each other such as setting up small radio LANs between any types of Bluetooth
devices. A number of user scenarios are described. They highlight more
possibilities that reach far beyond just an elimination of the point-to-point
cable.<o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: "Times New Roman","serif"; font-size: 14.0pt; mso-fareast-font-family: "Times New Roman";">History<o:p></o:p></span></b></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">         <o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">By the way if, you're wondering where the Bluetooth name
originally came from , it is named after a Danish Viking and King <b>of
Denmark between 940 and 981 AD</b>, Harald Blåtand (Bluetooth in English), who
lived in the latter part of the 10<sup>TH</sup>  century. Harald
Blåtand united and controlled Denmark and Norway (hence the inspiration on the
name : uniting devices through Bluetooth<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">          The
idea that resulted in the Bluetooth wireless technology was born in 1994 when Ericsson
Mobile Communications decided to investigate the feasibility of a low-power,
low-cost radio interface between mobile phones and their accessories. The idea
was that a small radio built into both the cellular telephone and the laptop
would replace the cumbersome cable used today to connect the two devices.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">A year later the engineering work began and the true potential of
the technology began to crystallize. But beyond unleashing devices by replacing
cables, the radio technology showed possibilities to become a universal bridge
to existing data networks, a peripheral interface, and a mechanism to form
small private ad hoc groupings of connected devices away from fixed network
infrastructures.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The requirements regarding price, capacity and size were set so
that the new technique would have the potential to outdo all cable solutions
between mobile devices. Initially a suitable radio interface with a
corresponding frequency range had to be specified. A number of criteria for the
concept were defined regarding size, capacity and global uniformity. The radio
unit should be so small and consume such low power that it could be fitted into
portable devices with their limitations. The concept had to handle both speech
and data and finally the technique had to work all around the world. The study
soon showed that a short-range radio link solution was feasible.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">When designers at Ericsson had started to work on a transceiver
chip, Ericsson soon realized that they needed companions to develop the
technique. The associates strove not only to improve the technical solutions
but also to get a solid and broad market support in the business areas of PC
hardware, portable computers and mobile phones. Fear for a market situation
with a multitude of non-standard cable solutions, where one cable is designed
specifically for one pair of devices, was one of the motives that made
competing companies join the project. Ericsson Mobile Communications, Intel,
IBM, Toshiba and Nokia Mobile Phones formed a Special Interest Group (SIG) in
1998.<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><br />
<b>What is  SIG?</b><o:p></o:p></span></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">          </span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">In February 1998 the Special Interest Group
(SIG) was formed. Today the Bluetooth SIG includes promoter companies 3Com,
Ericsson, IBM, Intel, Lucent, Microsoft, Motorola, Nokia and Toshiba, and
thousands of Adopter/Associate member companies. By signing a zero cost
agreement, companies can join the SIG and qualify for a royalty-free license to
build products based on the Bluetooth technology.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">This group represented the diverse market support that was needed
to generate good support for the new Bluetooth<i> </i>technology. In May
of the same year, the Bluetooth consortium announced itself globally. The
assignment of the SIG originally was to monitor the technical development of
short-range radio and to create an open global standard, thus preventing the
technology from becoming the property of a single company. This work resulted
in the release of the first Bluetooth Specification in July 1999.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The intention of the Bluetooth SIG is to form a de facto standard
for the air interface and the software that controls it.  The further
development of the Specification still is one of the main tasks for the SIG,
other important ones being interoperability requirements, frequency band
harmonization and promotion of the technology. The Bluetooth wireless
technology was developed by the Bluetooth Special Interest Group, to define an
industry-wide specification for connecting personal and business mobile
devices. More than 1,4000 companies are now members of the Special Interest
Group, signifying the industry’s unprecedented acceptance of the Bluetooth
wireless technology.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">To avoid different interpretations of the Bluetooth standard
regarding how a specific type of application should be mapped to Bluetooth, the
SIG has defined<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">number of user models
and protocol profiles. These are described in more detail in the section
entitled Bluetooth Usage Models and Profiles.The SIG also works with a
Qualification Process. This process defines criteria for bluetooth product
qualification that ensures that products that pass this process meet the
Bluetooth specification<o:p></o:p></span></div>
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<br /></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">TECHNOLOGY OVERVIEW:</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The technology is an open specification  for wireless
communication of data and voice. It is low cost short range radio link, built
into a 9X9 mm microchip, facilitating protected ad hoc connections for
stationary and mobile communication environment. Bluetooth technology allows
for the replacement of the many proprietary cables that connect one device to
another device with one universal short range radio link. For instance
Bluetooth radio technology built in both the cellular telephone and the laptop
would replace the cumbersome cables used today to connect the laptop to a
cellular telephone.<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">Printers, PDA’S, desktops, fax machines, keyboard, joysticks and
virtually any other device can be part of the Bluetooth system. But beyond
untethering devices by replacing the cables, Bluetooth radio technology
provides a universal bridge to existing data networks, a peripheral interface,
and a mechanism to form small private ad hoc grouping of connected devices away
from fixed network infrastructures. Designed to operate in noisy radio
frequency environment, the Bluetooth radio uses a fast acknowledgement and
frequency hopping scheme to make the link robust. The Bluetooth radio modules
avoid interference from other signals by hopping to a new frequency after
transmitting or receiving a packet. Compared with other systems operating in
the same frequency band, the Bluetooth radio typically hops faster and uses
shorter packets. This makes the Bluetooth radio robust than the other system.
Short packages and fast hopping also limit the impact of random noise and long
distance links. The encoding is optimized for uncoordinated environment.
Bluetooth radios operate in the unlicensed ISM band at 2.4GHz. a frequency hop
transceiver is applied to combat interference and fading. A shaped binary FM
modulation is applied to minimize transceiver complexity. The gross data rate
is 1mbps. A Time Division Duplex scheme is used for full duplex transmission.
The Bluetooth base band protocol is a combination of circuit and packet
switching. Slots can be reserved for synchronous packet. Each packet is
transmitted in a different hop frequency. A packet nominally covers a single
slot, but can be extended to cover up to 5 slots. Bluetooth can support an
asynchronous data channel, up to 3 simultaneous synchronous voice channels, or
a channel that simultaneously supports asynchronous data synchronous voice.
Each voice  channel supports 64 kbps synchronous (voice) link.<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The asynchronous channel can support an asymmetric link of
maximally 721 kbps in either direction  while permitting 57.6 kbps in
the return direction, or a 432.6 kbps symmetric link.<o:p></o:p></span></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">INTRODUCTION :</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The Bluetooth technology answers the need for short range wireless
connectivity within three areas :<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">·     Data and voice
access points .<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">·        Cable
replacement<o:p></o:p></span></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">·        Ad
hoc networking<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The Bluetooth technology specification specifies a system solution
comprising hardware, software and interoperability requirements. The Bluetooth
radio operates in a globally available 2.4GHz  ISM  band,
ensuring communication compatibility worldwide.       <o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">Data and voice access
point :</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The Bluetooth technology facilitates real time voice and data
transmission. The technology makes it possible to connect any portable and
stationary communication device as easily as switching on the light. You can,
for instance, surf the Internet & send e-mail on your potable PC or
notebook regardless of whether you are wirelessly connected through a mobile
phone or through a wire bound connection (PSTN, ISDN,LSN,XDLS).<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">          Voice
channel use the <i>Continuous Variable Slope Delta Modulation (CVSD</i>)
coding scheme, and never retransmit voice packets. The CVSD was chosen for its
robustness in handling dropped and damaged samples. Rising interference levels
are experienced as increased background noise; even at bit error rate up to 4%
the CVSD coded voice is quite audible.<o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">CABLE REPLACEMENT:</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"><o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">The Bluetooth technology
eliminates the use for numerous often proprietary cable attachments for
connection of practically any kind of device. Connections are instant and they
are maintained even when devices are not within line of sight. The range of
each radio is approximately 10 meters but it can be extended around 100 meters
with an optional amplifier.<o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">AD-HOC NETWORKING</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">:<o:p></o:p></span></div>
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<br /></div>
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<span style="font-family: 'Times New Roman', serif; font-size: 14pt;">A device equipped with Bluetooth radio establishes instant
connection to another Bluetooth radio as soon as it comes into range. Since
Bluetooth technology supports both point to point and point to multi point
connection, several piconets can be established and linked together ad hoc. The
Bluetooth technology is best described as multiple piconet structure.<o:p></o:p></span></div>
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<br /></div>
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<b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;">Piconet</span></b><span style="font-family: 'Times New Roman', serif; font-size: 14pt;"> is a connection of
devices connected via Bluetooth technology in an ad hoc fashion . A piconet
starts with two connected devices ,such as portable PC and cellular phone and
may grow into eight connected devices. All Bluetooth  devices are
peer units and have identical  implementation. However, when
establishing a piconet, one unit will act as a master and the other as a slave
for the duration of piconet connection.<o:p></o:p></span></div>
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What is Bluetooth?

Bluetooth wireless technology is a de facto standard, as well as a specification for small form factor, low-cost, short range radio links between mobile PCs, mobile phones and other portable devices. The Bluetooth Special Interest Group is an industry group consisting of leaders in the telecommunic…

24Apr2015

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