Research on Tenured Teachers in the School System Paper

On Tenured Teachers in the School System - Research Paper Example Yet another essential detail to be considered is delivered through the understanding of cost as a relative good. Teachers with good reputation and solid experience are often expensive, which can be regarded by school administration as a shortcoming. Tenure protects experienced teachers from being dismissed for this reason. On the other hand, this same issue of protection becomes the primary disadvantage of tenure when doubts of the teacher’s competence raise. Due to tenure, it might become a problem to fire such a teacher without primarily addressing a lot of bureaucratic issues at hand. Moreover, another disadvantage that should be addressed here is that undergoing the legislatively fixed procedure of firing a teacher is costly and thus a lot of institutions might ignore the necessity of dismissing a teacher based on this consideration alone. In order to avoid this problem, some institutions are prone to secrecy by providing a teacher to dismiss certain sum of money (Mathis, 2010). This allows the schools to avoid disclosure and the expensive, long and difficult process of firing a tenured teacher. There is a set of other pros and cons that should be considered when talking about teacher tenure. Among the pros, there is a notion that tenure is actually quite a useful and beneficial instrument when used correctly (McGuinn, 2010, p. 26). Tenure can create the environment that allows the teachers to improve as it creates healthy competition and motivates teachers without tenure to work harder to get it.

Michael Milken Essay Example | Topics and Well Written Essays - 500 words

Michael Milken - Essay Example Immediately after paying this debt, he resumed his lifelong philanthropic activities. Milken has promised that he will someday write his side of the controversy; but for now he feels it's less productive to focus on the past than to be involved in supporting the effort to accelerate medical solutions. Interviewer: Michael, that paragraph quoted from your website seems to imply that you don't believe you did anything wrong, that it was all a vast conspiracy to bring you down. Since you don't believe what you did was wrong, could you tell us whether you would do it again provided you didn't get caught MM: Ohh, that's a loaded question. First off let me point out that I violated the law and I was fined and I was imprisoned for almost 2 years of my life. So yes, what I did violated the law. There is a wider question though, and that is, how do we define what is wrong And I think that's the point being made on the website. The fact is I'm the only person in the history of that legislation to be prosecuted under it. And though I know I'm a fairly unique guy, I don't for one minute believe that I'm the only person who has violated that legislation.

Comparison of different modulation technique

Comparison of different modulation technique 1. INTRODUCTION 1.1 Modulation is the process of varying one waveform in relation to another waveform. In telecommunications, modulation is used to convey a message, or a musician may modulate the tone from a musical instrument by varying its volume, timing and pitch. Often a high-frequency sinusoid waveform is used as carrier signal to convey a lower frequency signal. The three key parameters of a sine wave are its amplitude (volume), its phase (timing) and its frequency (pitch), all of which can be modified in accordance with a low frequency information signal to obtain the modulated signal. A device that performs modulation is known as a modulator and a device that performs the inverse operation of modulation is known as a demodulator (sometimes detector or demod). 1.2 TWO TYPES OF MODULATION A) Analog modulation B) Digital modulation Here we discuss analog modulation techniques. 2. AMPLITUDE MODULATION Amplitude modulation (AM) is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent. For example, changes in the signal strength can be used to reflect the sounds to be reproduced by a speaker, or to specify the light intensity of television pixels. (Contrast this with frequency modulation, also commonly used for sound transmissions, in which the frequency is varied; and phase modulation, often used in remote controls, in which the phase is varied). 2.1 TYPES OF AMPLITUDE MODULATION As originally developed for the electric telephone, amplitude modulation was used to add audio information to the low-powered direct current flowing from a telephone transmitter to a receiver. As a simplified explanation, at the transmitting end, a telephone microphone was used to vary the strength of the transmitted current, according to the frequency and loudness of the sounds received. Then, at the receiving end of the telephone line, the transmitted electrical current affected an electromagnet, which strengthened and weakened in response to the strength of the current. In turn, the electromagnet produced vibrations in the receiver diaphragm, thus closely reproducing the frequency and loudness of the sounds originally heard at the transmitter. In contrast to the telephone, in radio communication what is modulated is a continuous wave radio signal (carrier wave) produced by a radio transmitter. In its basic form, amplitude modulation produces a signal with power concentrated at the carrier frequency and in two adjacent sidebands. This process is known as heterodyning. Each sideband is equal in bandwidth to that of the modulating signal and is a mirror image of the other. Amplitude modulation that results in two sidebands and a carrier is often called double sideband amplitude modulation (DSB-AM). Amplitude modulation is inefficient in terms of power usage and much of it is wasted. At least two-thirds of the power is concentrated in the carrier signal, which carries no useful information (beyond the fact that a signal is present); the remaining power is split between two identical sidebands, though only one of these is needed since they contain identical information. To increase transmitter efficiency, the carrier can be removed (suppressed) from the AM signal. This produces a reduced-carrier transmission or double-sideband suppressed-carrier (DSBSC) signal. A suppressed-carrier amplitude modulation scheme is three times more power-efficient than traditional DSB-AM. If the carrier is only partially suppressed, a double-sideband reduced-carrier (DSBRC) signal results. DSBSC and DSBRC signals need their carrier to be regenerated (by a beat frequency oscillator, for instance) to be demodulated using conventional techniques. Even greater efficiency is achieved—at the expense of increased transmitter and receiver complexity—by completely suppressing both the carrier and one of the sidebands. This is single-sideband modulation, widely used in amateur radio due to its efficient use of both power and bandwidth. A) DSB-FC In radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, containing power as a result of the modulation process. The sidebands consist of all the Fourier components of the modulated signal except the carrier. All forms of modulation produce sidebands. Amplitude modulation of a carrier wave normally results in two mirror-image sidebands. The signal components above the carrier frequency constitute the upper sideband (USB) and those below the carrier frequency constitute the lower sideband (LSB). In conventional AM transmission, the carrier and both sidebands are present, sometimes called double sideband amplitude modulation (DSB-AM). In some forms of AM the carrier may be removed, producing double sideband with suppressed carrier (DSB-SC). An example is the stereophonic difference (L-R) information transmitted in FM stereo broadcasting on a 38kHz subcarrier. The receiver locally regenerates the subcarrier by doubling a special 19kHz pilot tone, but in other DSB-SC systems the carrier may be regenerated directly from the sidebands by a Costas loop or squaring loop. This is common in digital transmission systems such as BPSK where the signal is continually present. B) SSB-SC Single-sideband modulation (SSB) is a refinement of amplitude modulation that more efficiently uses electrical power and bandwidth. Amplitude modulation produces a modulated output signal that has twice the bandwidth of the original baseband signal. Single-sideband modulation avoids this bandwidth doubling, and the power wasted on a carrier, at the cost of somewhat increased device complexity. C) SUPPERESED CARRIER Reduced-carrier transmission is an amplitude modulation (AM) transmission in which the carrier wave level is reduced to reduce wasted electrical power. Suppressed-carrier transmission is a special case in which the carrier level is reduced below that required for demodulation by a normal receiver. Reduction of the carrier level permits higher power levels in the sidebands than would be possible with conventional AM transmission. Carrier power must be restored by the receiving station to permit demodulation, usually by means of a beat frequency oscillator (BFO). Failure of the BFO to match the original carrier frequency when receiving such a signal will cause a heterodyne. Suppressed carriers are often used for single sideband (SSB) transmissions, such as for amateur radio on shortwave. That system is referred to in full as SSB suppressed carrier (SSBSC) or (SSB-SC). International broadcasters agreed in 1985 to also use SSBSC entirely by 2015, though IBOC and IBAC digital radio (namely Digital Radio Mondiale) seems likely to make this irrelevant. D) VSB A vestigial sideband (in radio communication) is a sideband that has been only partly cut off or suppressed. Television broadcasts (in analog video formats) use this method if the video is transmitted in AM, due to the large bandwidth used. It may also be used in digital transmission, such as the ATSC standardized 8-VSB. The Milgo 4400/48 modem (circa 1967) used vestigial sideband and phase-shift keying to provide 4800-bit/s transmission over a 1600 Hz channel. E) QAM Quadrature amplitude modulation (QAM) is both an analog and a digital modulation scheme. It conveys two analog message signals, or two digital bit streams, by changing (modulating) the amplitudes of two carrier waves, using the amplitude-shift keying (ASK) digital modulation scheme or amplitude modulation (AM) analog modulation scheme. These two waves, usually sinusoids, are out of phase with each other by 90Â ° and are thus called quadrature carriers or quadrature components — hence the name of the scheme. The modulated waves are summed, and the resulting waveform is a combination of both phase-shift keying (PSK) and amplitude-shift keying, or in the analog case of phase modulation (PM) and amplitude modulation. In the digital QAM case, a finite number of at least two phases, and at least two amplitudes are used. PSK modulators are often designed using the QAM principle, but are not considered as QAM since the amplitude of the modulated carrier signal is constant. 3) FREQUENCY MODULATION frequency modulation (FM) conveys information over a carrier wave by varying its frequency (contrast this with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant). In analog applications, the instantaneous frequency of the carrier is directly proportional to the instantaneous value of the input signal. Digital data can be sent by shifting the carriers frequency among a set of discrete values, a technique known as frequency-shift keying. CARSONS RULE A rule of thumb, Carsons rule states that nearly all (~98%) of the power of a frequency-modulated signal lies within a bandwidth of where , as defined above, is the peak deviation of the instantaneous frequency from the center carrier frequency . Normal signal Modulated signal 4) PHASE MODULATION Phase modulation (PM) is a form of modulation that represents information as variations in the instantaneous phase of a carrier wave. Unlike its more popular counterpart, frequency modulation (FM), PM is not very widely used. This is because it tends to require more complex receiving hardware and there can be ambiguity problems in determining whether, for example, the signal has changed phase by +180Â ° or -180Â °. CARSONS RULE Suppose that the signal to be sent (called the modulating or message signal) is m(t) and the carrier onto which the signal is to be modulated is Annotated: carrier(time) = (carrier amplitude)sin(carrier frequencytime + phase shift) This make the modulated signal This shows how m(t) modulates the phase the greater m(t) is at a point in time, the greater the phase shift of the modulated signal at that point. It can also be viewed as a change of the frequency of the carrier signal, and phase modulation can thus be considered a special case of FM in which the carrier frequency modulation is given by the time derivative of the phase modulation. The spectral behaviour of phase modulation is difficult to derive, but the mathematics reveals that there are two regions of particular interest: For small amplitude signals, PM is similar to amplitude modulation (AM) and exhibits its unfortunate doubling of baseband bandwidth and poor efficiency. For a single large sinusoidal signal, PM is similar to FM, and its bandwidth is approximately, where fM = ωm / 2Ï€ and h is the modulation index defined below. This is also known as Carsons Rule for PM 5) SPACE MODULATION Space modulation is a radio Amplitude Modulation technique used in Instrument Landing Systems that incorporates the use of multiple antennas fed with various radio frequency powers and phases to create different depths of modulation within various volumes of three-dimensional airspace. This modulation method differs from internal modulation methods inside most other radio transmitters in that the phases and powers of the two individual signals mix within airspace, rather than in a modulator.

Comparing Red Badge of Courage and Great Expectations :: comparison compare contrast essays

Red Badge of Courage and Great Expectations The hero of The Red Badge of Courage, which was written by Stephen Crane in the late 1800s, was a young private named Henry Fleming, who was fighting for the North in the American Civil War. Like Pip, in Great Expectations, Henry was a commoner. He was new to the Army and few people knew his name. The main difference between Henry and the earlier heroes is that Henry was not born with leadership qualities or traits like bravery. In fact, in the first battle he fought, he proved himself to be a coward by running from it. Henry's flaws were very similar to those of Pip and the Greek heroes. Arrogance was a flaw that many Greek mortal heroes, especially Odysseus and Oedipus, had. When Henry realized that none of his fellow soldiers were aware that he had run from the first battle, he regained his self-pride and self-confidence. Before long, he had convinced himself that he was "chosen of the gods and doomed to greatness." At first, Pip believed that status and wealth determined the "goodness" of a person. Henry had similar illusions. He believed that a war hero was a person who could manage to escape every tight situation he got into, and also a godly figure people looked up to and were fascinated by. His other illusions were that the only the best could survive against the hideous "dragons" of war, and that the enemy was a machine that never tired or lost will to fight. An important difference between Henry and the Greek heroes was that Henry's flaws were recognized by the people of Crane's day, whereas the Greeks did not see any flaws in their heroes, like Odysseus (they thought traits like arrogance were cool). Another difference between Henry and the Greek heroes can be seen in their heroic acts. Greek war heroes were praised for their outward bravery and military genius (how many enemy soldiers they killed, or how they were able to trick the enemy). Near the end, Henry was a war hero in the eyes of his fellow soldiers and commanding officers (he fought fearlessly and led charges), but what was truly heroic about Henry was the way he changed and developed.

Ethnic Background Essay

My name is Stephanie Flowers and until this class assignment I never thoughtfully considered what my actual ethnic background was. After looking up the meaning of my last name I found it to be of Welsh origin. This means that I could possibility trace my family roots back to Great Britain. After reading chapter one of Race and Ethnic Relations I discovered that being a part of a certain ethnic background does not mean that you have to be part of that race, but you have to practice the common cultural traditions of that subculture. So based off of my name some people might think that I was English. I grew up with a few household traditions that I consider to be a part of my ethnic background. To begin with, I would consider my family to practice Irish traditions. We always have huge St. Patrick’s Day party at my house that turns into an all-day drinking and eating celebration. I might not know all the reasons behind this celebration and what I consider a part of my family tradition, but it is still a part of my ethnic background in my opinion. Drinking is a big part of being Irish and in my family most celebrations do involve some type of alcohol. In Irish culture it is normal to introduce alcohol to children before the actual drinking age, I think this is good because we grow up with this around us and never take consumption of alcohol to extremes because it such a part of everyday life. I am would also consider myself to be of German ethnicity. My family has a good luck tradition for New Years. We eat pork roast and sauerkraut in hopes that the next year will be filled with lots of happiness and joy. I personally love this tradition and get upset when I sometimes only get to eat this meal once a year. It is one of my top five meals to eat that my grandma cooks. Being from the United States of America I do think that I have picked up so many different traditions from all of the friends that I have had throughout my life. This is why I love living in this country I get to experience so many different cultures and ethnic backgrounds. My boyfriend is of the Catholic religion, his family maintains this culture by attending mass for Christmas, Easter, and whenever they feel the need strengthen their relationship with god. This is the way that they maintain their ethnic background. They are a common group of people who believe the idea that they all share the share cultural heritage. This stems from his Irish background where Catholicism is the main religion practiced in that country. So to me this is the way to stay in touch with being from Ireland even though they now live in America. My cousin Rachael is half Mexican. Her mom was an immigrant and came to this country to start a better life. I love getting to go to their house in Texas; her mom makes the best Mexican dishes. What I have noticed from her Mexican culture and ethnicity is that food is a way of bringing the family together, it is a time of bonding in their household. I believe that by cooking traditional Mexican food it keeps her in touch with her roots and makes her feel better connected to her homeland. After doing this assignment I am very interested in doing more research on my family roots and discovering more about who and where I came from. Like it says on the Ancestry. com commercial, â€Å"you don’t have to know what you’re looking for; you just have to start looking. † So that’s what I am going to start doing. Also, I would like to conduct interviews with the elderly people in my family and possibility start filling out my family tree, which would be an easy way to connect the dots of my family history. I will still continue to maintain my Irish and German background by drinking on St. Patrick’s Day and eating pork roast and sauerkraut. I am very proud to be an American and I wish I didn’t take all of the rights that I have in this country for granite.

The Fashion of Warriors

Memoirs off Secret Empire . Samurai I PBS Search Support for PBS. Org provided by: What's this? Sam aura warriors me urged as an elite force in Japan's prop inches during the early 1 20th century . Recruited by local chieftains, these fighting forces were m maintained long enough to wage a specific war, after which the soldiers would return to their lands to till the soil. With Japan's me proper live ins in the ancient capital of Ky tot and unable to m maintain control of the prop inches, the Sam aura clans established them sell sees as v table political entities.By the late 1 2 the century , Sam aura lords ruled both the prop inches and central Japan. They m maintained their influence until the m id-1 87 g's when the Sam aura class was outlawed and their privy ledge status was dissolve deed. Samurai warriors were at the top of the social order CASTE POSITION The Sam aura class, â€Å"shim in,† form deed Japan's top elite, and were the only caste granted the privy liege of wea ring two swords and have ins two name sees?a fame ill and a first name e.The shoguns and Adam y o lords were m me beers of the shim in caste. THEN & NOW Modern Japan still m maintains a culture based on the incepts of 1/3 The rigorous training of a Sam aura warrior began in childhood. Sam aura school was a unique com abomination of pay sisal training, Chinese studies, poetry and spiritual discipline. The y nouns warriors studied Keno (â€Å"the Way of the Sword†), the m oral code of the Sam aura, and Zen www. PBS. Org/empires/Japan/entered_8. HTML Buddhism .Sam aura were expected to live e according to Bushier (â€Å"The Way of the Warrior†), a strict ethical code influenced by Confucianism that stressed LOL alt to one's m aster, respect for one's superior, ethical behave ROR in all aspects of life and mom plate self-discipline. Girls also receive deed m arterial arts training. Although m cost Sam aura whom en did not fight on the battlefield, they were prepared to def end their homo sees against NV adders. The Sam aura attached great IM portable to the circus stances of their own death.If a Sam aura died of his own accord, it was considered a v Lillian end. Rather than suffer defeat or hum location at the hands of an enema y , Sam aura warriors often chose ritual suicide (speedup). After Outgas lye ass united Japan, Sam aura m litany serve ices were rarely needed. Though they continued to train daily , Sam aura gradually transform deed from warriors to bureaucrats. As townspeople acquired new wealth, the Sam aura, barred from engaging in com m race, found them sell sees in dire circus stances. For m any Sam aura, peace led to despair. Nor and sham e, funded mental to the Sam aura code. Sam aura warriors took great care sty ling their hair, which they pulled back into a topknot called a â€Å"chomp age. † For battle, Sam aura warriors shave deed the tops of their heads, which reduced the heat under their heave y helm test, and ore their hai r straight on the sides. When not wearing helm test, they pulled the side and back hair into a topknot. A Sam Uri's clothing sty el was v ere IM portent and indicative e of status. Outlandish, colorful patterns were considered IM m oddest and conceited.Though Sam aura children dressed flam boy antsy , they became e m ore subdued in appearance after their com ins-of-age Ceres non . The Sam Uri's eve ere day wear was a Kim non, usually consisting of an outer and inner lay ere. Norm ally m add of silk, the quality of the Kim non depended on the Sam Uri's income e and status. Beneath the Kim non, the warrior wore a loincloth. The Sam Uri's swords were norm ally thrust through an â€Å"Obi,† a belt wrapped around the waist, and were always s worn on the left side.

Cloud Computing Essay Example

Cloud Computing Essay Example Cloud Computing Essay Cloud Computing Essay Web-Based Applications That Change the Way You Work and Collaborate Online Page 1 Return to Table of Contents CLOUD COMPUTING Web-Based Applications That Change he Way You Work and Collaborate Online Michael Miller 800 East 96th Street, Indianapolis, Indiana 46240 Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Page 2 Return to Table of Contents Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Copyright  © 2009 by Que Publishing All rights reserved.No part of this book shall be reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechani- cal, photocopying, recording, or otherwise, without written permission from the publisher. No patent liability is assumed with respect to the use of the information contained herein. Although every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility for errors or omissions. Nor is any lia- bility assumed for damages resulting from the use of the information contained herein. ISBN-13: 978-0-7897-3803-5 ISBN-10: 0-7897-3803-1Library of Congress Cataloging-in-Publication data is on file. Printed in the United States of America First Printing: August 2008 Trademarks All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Que Publishing cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting the validity of any trade- mark or service mark. Warning and Disclaimer Every effort has been made to make this book as complete and as accu- rate as possible, but no warranty or fitness is implied. The information provided is on an as is basis.The author and the publisher shall have neither liability nor responsibility to any person or entity with respect to any loss or damages arising from the information contained in this book. Bulk Sales Que Publishing offers excellent discounts on this book when ordered in quantity for bulk purchases or special sales. For more information, please contact U. S. Corporate and Government Sales 1-800-382-3419 [emailprotected] com For sales outside of the U. S. , please contact International Sales [emailprotected] com Associate Publisher Greg Wiegand Acquisitions Editor Rick Kughen Development Editor Rick KughenManaging Editor Patrick Kanouse Project Editor Seth Kerney Copy Editor Keith Cline Indexer Tim Wright Proofreader Paula Lowell Technical Editor/Reviewer Aaron Ricadela Publishing Coordinator Cindy Teeters Book Designer Anne Jones Page Layout Bronkella Publishing LLC Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Page 3 Return to Table of Contents About the Author Michael Miller is a successful and prolific author.He is known for his casual, easy-to-read writing style and his ability to explain a wide variety of complex topics to an everyday audience. Mr. Miller has written more than 80 nonfiction books over the past two decades, with more than a million copies in print. His books for Que include Absolute Beginner’s Guide to Computer Basics, How Microsoft Windows Vista Works, Making a Living from Your eBay Business, Googlepedia: The Ultimate Google Resource, and Is It Safe? Protecting Your Computer, Your Business, and Yourself Online. You can email Mr. Miller directly at [emailprotected] com. His website is located at www. olehillgroup. com. Dedication To Sherry. Life is a cloud. Acknowledgments Thanks to the usual suspects at Que, including but not limited to Greg Wiegand, Rick Kughen, Seth Kerney Keith Cline, and technical editor Aaron Ricadela. Cloud Computing: W eb-Based Applications That Change the Way You Work and Collaborate Online Page 4 Return to Table of Contents We Want to Hear from You! As the reader of this book, you are our most important critic and commenta- tor.We value your opinion and want to know what we’re doing right, what we could do better, what areas you’d like to see us publish in, and any other words of wisdom you’re willing to pass our way. As an associate publisher for Que Publishing, I welcome your comments. You can email or write me directly to let me know what you did or didn’t like about this book- as well as what we can do to make our books better. Please note that I cannot help you with technical problems related to the topic of this book We do have a User Services group, however, where I will forward specific technical questions related to the bookWhen you write, please be sure to include this book’s title and author as well as your name, email address, and phone number. I wi ll carefully review your comments and share them with the author and editors who worked on the book. Email: [emailprotected] com Mail: Greg Wiegand Associate Publisher Que Publishing 800 East 96th Street Indianapolis, IN 46240 USA Reader Services Visit our website and register this book at informit. com/register for convenient access to any updates, downloads, or errata that might be available for this book.Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Page 5 Return to Table of Contents Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Page 6 Return to Table of Contents Introduction IntroductionComputing as you know it is about to change: Your applications and documents are going to move from the desktop into the cloud. I’m talking about cloud computing, where applications and files are hosted on a cloud consisting of thousands of com- puters and servers, all linked together and accessible via the Internet. With cloud computing, everything you do is now web based instead of being desktop based. You can access all your programs and documents from any computer that’s connected to the Internet. How will cloud computing change the way you work? For one thing, you’re no longer tied to a single computer.You can take your work anywhere because it’s always accessible via the web. In addition, cloud computing facilitates group collaboration, as all group members can access the same programs and documents from wherever they happen to be located. Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Page 7 Return to Table of Contents 2 Cloud ComputingCloud computing might sound far-fetched, but chances are you’re already using some cloud applications. If you’re using a web-based email program, such as Gmail or Hotmail, you’re computing in the cloud. If you’re using a web-based application suc h as Google Calendar or Apple MobileMe, you’re computing in the cloud. If you’re using a file- or photo-sharing site, such as Flickr or Picasa Web Albums, you’re computing in the cloud. It’s the technol- ogy of the future, available to use today. How does cloud computing work? What does cloud computing mean for the way you use a computer?What are the top cloud computing applications? Good questions all, and all answered in this book: Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online. I don’t pre- tend to answer every question you may have (the overly technical ones in particular), but I do try to give you a good solid overview of the cloud comput- ing phenomenon, and introduce you to some of the more popular cloud applications- in particular, those that facilitate group collaboration. And that’s where cloud computing really shines.Whether you want to share photographs with family members, coordinate volunteers for a community organization, or manage a multifaceted project in a large organization, cloud computing can help you collaborate and communicate with other group members. You’ll have a better idea of how this works after you read the book, but trust me on this one- if you need to collaborate, cloud computing is the way to do it. How This Book Is Organized Cloud computing is actually a pretty simple concept, but one with lots of vari- ations and ramifications.To help you better understand what cloud comput- ing is and what it does, I’ve organized this book into four major parts:  ¦ Part I, Understanding Cloud Computing, is the place for you to start learning about cloud computing. I explain how cloud computing works and examine which types of users can best benefit from this new technology.  ¦ Part II, Cloud Computing for Everyone, examines the practical bene- fit of cloud computing for users in three different scenarios: in the fam- ily, in the community and in the large organization. Part III, Using Cloud Services, is an overview of various types of web- based applications. You’ll learn about cloud services for scheduling, contact management, project management, word processing, presenta- tions, and other key applications. Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Page 8 Return to Table of Contents INTRODUCTION 3  ¦ Part IV, Outside the Cloud: Other Ways to Collaborate Online, moves eyond strict cloud computing to examine other Internet-based tools for group collaboration, including web email, instant messaging, social networks, online groupware, blogs, and wikis. Taken together, the 20 chapters in this book provide an excellent overview of cloud computing. If you’re not sure what cloud computing is yet, you will be when you get done reading this book. Conventions Used in This Book I hope that this book is easy enough to figure out on its own, without requir- ing it s own instruction manual. As you read through the pages, however, it helps to know precisely how I’ve presented specific types of information.Web Page Addresses There are a lot of web page addresses in this book. They’re noted as such: www. molehillgroup. com Technically, a web page address is supposed to start with http:// (as in molehillgroup. com). Because Internet Explorer and other web browsers automatically insert this piece of the address, however, you don’t have to type it- and I haven’t included it in any of the addresses in this book. Cloud Services I also list a lot of web-based applications and services in this book; after all, that’s what cloud computing is all about.Know, however, that companies are constantly changing prices, coming out with new features, introducing com- pletely new services, and discontinuing older ones. With that in mind, every service and URL listed in this book is valid as of June 2008; chances are, how- ever, that something will change by the time you read the book. Special Elements This book includes two special elements that provide additional information not included in the basic text. These elements are designed to supplement the text to make it your learning faster, easier, and more efficient.Cloud Computing: Web-Based Applications That Change the Way You Work and Collaborate Online Page 9 Return to Table of Contents Cloud Computing In addition, I end each chapter with a side- bar- a chunk of text that goes beyond what is presented in the normal chapter text to provide additional information that may be of interest to you. I find these side- bars interesting but not necessarily essen- tial; you may or may not feel the same. note A note is designed to provide information that is generally useful but not pecifically necessary for what you’re doing at the moment. tip A tip offers additional advice that might prove useful to the task at hand. Let Me Know What You Think I always l ove to hear from readers. If you want to contact me, feel free to email me at [emailprotected] com. I can’t promise that I’ll answer every message, but I do promise to read each one! If you want to learn more about me and any new books I have cooking, check out my Molehill Group website at www. molehillgroup. com. Who knows- you might A caution warns you of a particular situation-be alert to .the warning! ind some other books there that you’d like to read. 4 [pic] CHAPTER 1 Beyond the Desktop: An Introduction to Cloud Computing n a world that sees new technological trends bloom and fade on almost a daily basis, one new trend promises more longevity. This trend is called cloud computing, and it will change the way you use your computer and the Internet. Cloud computing portends a major change in how we store information and run applications. Instead of running programs and data on an individual desktop computer, every-thing is hosted in the cloud- a nebulous asse mblage ofcomputers and servers accessed via the Internet.Cloud computing lets you access all your applications and docu-ments from anywhere in the world, freeing you from the confines of the desktop and making it easier for group mem-bers in different locations to collaborate. fe3 Cloud Computing: What It Is and What It Isn’t From Collaboration to the Cloud: A Short History of Cloud Computing . The Network Is the Computer: How Cloud Computing Works Companies in the Cloud: Cloud Computing Today Why Cloud Computing Matters Cloud 8 PART I Understanding Cloud ComputingThe emergence of cloud computing is the computing equivalent of the electric-ity revolution of a century ago. Before the advent of electrical utilities, every farm and business produced its own electricity from freestanding generators. After the electrical grid was created, farms and businesses shut down their generators and bought electricity from the utilities, at a much lower price (and with much greater reliabil ity) than they could produce on their own. Look for the same type of revolution to occur as cloud computing takes hold.The desktop-centric notion of computing that we hold today is bound to fall by the wayside as we come to expect the universal access, 24/7 reliability, and ubiquitous collaboration promised by cloud computing. It is the way of the future. Cloud Computing: What It Is-and What It Isn’t With traditional desktop computing, you run copies of software programs on each computer you own. The documents you create are stored on the com- puter on which they were created. Although documents can be accessed from other computers on the network, they can’t be accessed by computers outside the network.The whole scene is PC-centric. With cloud computing, the software programs you use aren’t run from your personal computer, but are rather stored on servers accessed via the Internet. If your computer crashes, the software is still available for others to use. Same goes for the documents you create; they’re stored on a collection of servers accessed via the Internet. Anyone with permission can not only access the documents, but can also edit and collaborate on those documents in realtime. Unlike traditional computing, this cloud computing model isn’t PC- centric, it’s document-centric.Which PC you use to access a document simply isn’t important. But that’s a simplification. Let’s look in more detail at what cloud computing is- and, just as important, what it isn’t. What Cloud Computing Isn’t First, cloud computing isn’t network computing. With network computing, applications/documents are hosted on a single company’s server and accessed over the company’s network. Cloud computing is a lot bigger than that. It encompasses multiple companies, multiple servers, and multiple networks. Plus, unlike network computing, cloud services and storage are accessible fromC H A P T E R 1 Beyond the Desktop: An Introduction to Cloud Computing anywhere in the world over an Internet connection; with network computing, access is over the company’s network only. Cloud computing also isn’t traditional outsourcing, where a company farms out (subcontracts) its computing services to an outside firm. While an out-sourcing firm might host a company’s data or applications, those documents and programs are only accessible to the company’s employees via the com-pany’s network, not to the entire world via the Internet. So, despite superficial similarities, etworking computing and outsourcing are not cloud computing. What Cloud Computing Is Key to the definition of cloud computing is the cloud itself. For our purposes,the cloud is a large group of interconnected computers. These computers can be personal computers or network servers; they can be public or private. For example, Google hosts a cloud that consists of both smallish PCs and larg er servers. Google’s cloud is a private one (that is, Google owns it) that is publicly accessible (by Google’s users). This cloud of computers extends beyond a single company or enterprise.The applications and data served by the cloud are available to broad group of users, cross-enterprise and cross-platform. Access is via the Internet. Any authorized user can access these docs and apps from any computer over any Internet connection. And, to the user, the technology and infrastructure behind the cloud is invisible. It isn’t apparent (and, in most cases doesn’t mat-ter) whether cloud services are based on HTTP, HTML, XML, JavaScript, or other specific technologies. It might help to examine how one of the pioneers of cloud computing,Google, perceives the topic.From Google’s perspective, there are six key prop-erties of cloud computing:  ¦ Cloud computing is user-centric. Once you as a user are connected to the cloud, whatever is stored there- docum ents, messages, images, applications, whatever- becomes yours. In addition, not only is the data yours, but you can also share it with others. In effect, any device that accesses your data in the cloud also becomes yours.  ¦ Cloud computing is task-centric. Instead of focusing on the applica-tion and what it can do, the focus is on what you need done and how the application can do it for you. Traditional applications- word pro-cessing, spreadsheets, email, and so on- are becoming less important than the documents they create. 9 10PART IUnderstanding Cloud Computing  ¦ Cloud computing is powerful. Connecting hundreds or thousands of computers together in a cloud creates a wealth of computing power impossible with a single desktop PC.  ¦ Cloud computing is accessible. Because data is stored in the cloud, users can instantly retrieve more information from multiple reposito-ries. You’re not limited to a single source of data, as you are with a desktop PC. Cloud computing is intelligent. With all the various data stored on the computers in a cloud, data mining and analysis are necessary to access that information in an intelligent manner.  ¦ Cloud computing is programmable. Many of the tasks necessary with cloud computing must be automated. For example, to protect the integrity of the data, information stored on a single computer in the cloud must be replicated on other computers in the cloud. If that one computer goes offline, the cloud’s programming automatically redis- tributes that computer’s data to a new computer in the cloud.All these definitions behind us, what constitutes cloud computing in the real world? As you’ll learn throughout this book, a raft of web-hosted, Internet-accessible, group-collaborative applications are currently available, with many more onthe way. Perhaps the best and most popular examples of cloud computing applications today are the Google family of applications- Google Docs Spreadsheets, Google C alendar, Gmail, Picasa, and the like. All of these appli-cations are hosted on Google’s servers, are accessible to any user with an Internet con-nection, and can be used for group collab-oration from anywhere in the world.In short, cloud computing enables a shift from the computer to the user, from appli-cations to tasks, and from isolated data to data that can be accessed from anywhere and shared with anyone. The user no longer has to take on the task of data management; he doesn’t even have to remember where the data is. All that mat-ters is that the data is in the cloud, and thus immediately available to that user and to other authorized users. Note: Developers and IT types might have a slightly different definition of cloud computing than that for an end user.To the people who develop and manage computer systems, cloud computing is all about horizontal scalability in the form of server capability; the technical challenge is developing operating systems and applica- tions to manage this sort of on-the-fly scaling-while keeping the mechanics of it invisible to , the end user. CHAPTER 1 Beyond the Desktop: An Introduction to Cloud Computing 11 From Collaboration to the Cloud: A Short History of Cloud Computing Cloud computing has as its antecedents both client/server computing and peer-to-peer distributed computing.It’s all a matter of how centralized storage facilitates collaboration and how multiple computers work together to increase computing power. Client/Server Computing: Centralized Applications and Storage In the antediluvian days of computing (pre-1980 or so), everything operated on the client/server model. All the software applications, all the data, and all the control resided on huge mainframe computers, otherwise known as servers. If a user wanted to access specific data or run a program, he had to connect to the mainframe, gain appropriate access, and then do his business while essen-tially renting the program or data from th e server.Users connected to the server via a computer terminal, sometimes called a workstation or client. This computer was sometimes called a dumb terminal because it didn’t have a lot (if any! ) memory, storage space, or processing power. It was merely a device that connected the user to and enabled him to use the mainframe computer. Users accessed the mainframe only when granted permission, and the infor- mation technology (IT) staff weren’t in the habit of handing out access casu-ally. Even on a mainframe computer, processing power is limited- and the IT staff were the guardians of that power.Access was not immediate, nor could two users access the same data at the same time. Beyond that, users pretty much had to take whatever the IT staff gave them- with no variations. Want to customize a report to show only a subset of the normal information? Can’t do it. Want to create a new report to look at some new data? You can’t do it, although the IT staff ca n- but on their schedule, which might be weeks from now. The fact is, when multiple people are sharing a single computer, even if that computer is a huge mainframe, you have to wait your turn.Need to rerun a financial report? No problem- if you don’t mind waiting until this afternoon,or tomorrow morning. There isn’t always immediate access in a client/server environment, and seldom is there immediate gratification. So the client/server model, while providing similar centralized storage, differed from cloud computing in that it did not have a user-centric focus; with client/server computing, all the control rested with the mainframe- and with the guardians of that single computer. It was not a user-enabling environment. 2 PART I Understanding Cloud Computing Peer-to-Peer Computing: Sharing Resources As you can imagine, accessing a client/server system was kind of a hurry up and wait experience. The server part of the system also created a huge bottle-neck. All communica tions between computers had to go through the server first, however inefficient that might be. The obvious need to connect one computer to another without first hitting the server led to the development of peer-to-peer (P2P) computing.P2P computing defines a network architecture in which each computer has equivalent capa-bilities and responsibilities. This is in contrast to the traditional client/server network architecture, in which one or more computers are dedicated to serv-ing the others. (This relationship is sometimes characterized as a master/slave relationship, with the central server as the master and the client computer as the slave. ) P2P was an equalizing concept. In the P2P environment, every computer is a client and a server; there are no masters and slaves.By recognizing all com-puters on the network as peers, P2P enables direct exchange of resources and services. There is no need for a central server, because any computer can func-tion in that capacity when called on to do so. P2P was also a decentralizing concept. Control is decentralized, with all com-puters functioning as equals. Content is also dispersed among the various peer computers. No centralized server is assigned to host the available resources and services. Perhaps the most notable implementation of P2P computing is the Internet.Many of today’s users forget (or never knew) that the Internet was initially conceived, under its original ARPAnet guise, as a peer-to-peer system that would share computing resources across the United States. The various ARPAnet sites- and there weren’t many of them- were connected together not as clients and servers, but as equals. The P2P nature of the early Internet was best exemplified by the Usenet net-work. Usenet, which was created back in 1979, was a network of computers (accessed via the Internet), each of which hosted the entire contents of the net-work. Messages were propagated between the eer computers; users connect-ing to any si ngle Usenet server had access to all (or substantially all) the messages posted to each individual server. Although the users’ connection to the Usenet server was of the traditional client/server nature, the relationship between the Usenet servers was definitely P2P- and presaged the cloud com-puting of today. CHAPTER 1 Beyond the Desktop: An Introduction to Cloud Computing 13 That said, not every part of the Internet is P2P in nature. With the develop-ment of the World Wide Web came a shift away from P2P back to the client/server model.On the web, each website is served up by a group of com-puters, and sites’ visitors use client software (web browsers) to access it. Almost all content is centralized, all control is centralized, and the clients have no autonomy or control in the process. Distributed Computing: Providing More Computing Power One of the most important subsets of the P2P model is that of distributed com-puting, where idle PCs across a network or across th e Internet are tapped to provide computing power for large, processor-intensive projects.It’s a simple concept, all about cycle sharing between multiple computers. A personal computer, running full-out 24 hours a day, 7 days a week, is capa-ble of tremendous computing power. Most people don’t use their computers 24/7, however, so a good portion of a computer’s resources go unused. Distributed computing uses those resources. When a computer is enlisted for a distributed computing project, software is installed on the machine to run various processing activities during those peri-ods when the PC is typically unused.The results of that spare-time processing are periodically uploaded to the distributed computing network, and com-bined with similar results from other PCs in the project. The result, if enough computers are involved, simulates the processing power of much larger main-frames and supercomputers- which is necessary for some very large and com-plex computi ng projects. For example, genetic research requires vast amounts of computing power. Left to traditional means, it might take years to solve essential mathematical problems. By connecting together thousands or millions) of individual PCs, more power is applied to the problem, and the results are obtained that much sooner. Distributed computing dates back to 1973, when multiple computers were net-worked together at the Xerox PARC labs and worm software was developed to cruise through the network looking for idle resources. A more practical appli-cation of distributed computing appeared in 1988, when researchers at the DEC (Digital Equipment Corporation) System Research Center developed soft-ware that distributed the work to factor large numbers among workstations within their laboratory.By 1990, a group of about 100 users, utilizing this software, had factored a 100-digit number. By 1995, this same effort had been expanded to the web to factor a 130-digit number. 14PART IUnderstandin g Cloud Computing It wasn’t long before distributed computing hit the Internet. The first major Internet-based distributed computing project was distributed. net, launched in 1997, which employed thousands of personal computers to crack encryption codes. Even bigger was [emailprotected], launched in May 1999, which linked together millions of individual computers to search for intelligent life in outer space.Many distributed computing projects are conducted within large enterprises, using traditional network connections to form the distributed computing net-work. Other, larger, projects utilize the computers of everyday Internet users, with the computing typically taking place offline, and then uploaded once a day via traditional consumer Internet connections . Collaborative Computing: Working as a Group From the early days of client/server computing through the evolution of P2P, there has been a desire for multiple users to work simultaneously on the same computer-based proj ect.This type of collaborative computing is the driving force behind cloud computing, but has been around for more than a decade. Early group collaboration was enabled by the combination of several different P2P technologies. The goal was (and is) to enable multiple users to collaborate on group projects online, in real time. To collaborate on any project, users must first be able to talk to one another. In today’s environment, this means instant messaging for text-based commu-nication, with optional audio/telephony and video capabilities for voice and picture communication. Most collaboration systems offer the complete range of udio/video options, for full-featured multiple-user video conferencing. In addition, users must be able to share files and have multiple users work on the same document simultaneously. Real-time whiteboarding is also common, especially in corporate and education environments. Early group collaboration systems ranged from the relatively simple (Lotus N otes and Microsoft NetMeeting) to the extremely complex (the building-block architecture of the Groove Networks system). Most were targeted at large corporations, and limited to operation over the companies’ private networks.Note: Whiteboarding is where one or more users draw on a virtual white-board that is viewable by all the members of the group. C H A P T E R 1 Beyond the Desktop: An Introduction to Cloud Computing15 Cloud Computing: The Next Step in Collaboration With the growth of the Internet, there was no need to limit group collaboration to a single enterprise’s network environment. Users from multiple locations within a cor-poration, and from multiple organizations,desired to collaborate on projects that crossed company and geographic boundaries.To do this, projects had to be housed in the cloud of the Internet, and accessed from any Internet-enabled location. The concept of cloud-based documents and services took wing with the devel-opment of large server fa rms, such as those run by Google and other search companies. Google already had a collection of servers that it used to power its massive search engine; why not use that same computing power to drive a collection of web-based applications- and, in the process, provide a new level of Internet-based group collaboration?That’s exactly what happened, although Google wasn’t the only company offering cloud computing solutions. On the infrastructure side, IBM, Sun Systems, and other big iron providers are offering the hardware necessary to build cloud networks. On the software side, dozens of companies are develop-ing cloud-based applications and storage services. Today, people are using cloud services and storage to create, share, find, and organize information of all different types. Tomorrow, this functionality will be available not only to computer users, ut to users of any device that con-nects to the Internet- mobile phones, portable music players, even automo-biles and home television sets. Note: The term cloud com-puting is a relatively recent one, gaining prominence in 2007 as a means of describing Internet-based distributed com-puting and its associated applications. The Network Is the Computer: How Cloud Computing Works Sun Microsystems’s slogan is The network is the computer, and that’s as good as any to describe how cloud computing works. In essence, a network of computers functions as a single computer to serve data and applications to users over the Internet.The network exists in the cloud of IP addresses that we know as the Internet, offers massive computing power and storage capabil-ity and enables widescale group collaboration. But that