Now Article Posting by Mails By Anyone

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All the articles will be reviewed manullay by the Moderator and if articles were found not relevant to the Blog, those articles will be removed.

/Training Enhancers Team

Thursday, 14 March 2013

The Cloud, Day 4: Checking Out Google Docs


As I spelled out on Day 3 of 30 Days With the Cloud, I am going to spend a day with each of the three online productivity suites to see how they meet my needs. After taking a look at each, I'll pick the one I want to use for the remainder of the cloud series. So, let's start with Google Docs.

User Interface

I actually like the Microsoft ribbon interface, and I am used to working with Microsoft Office programs and files using the ribbon. By comparison, the Google Docs menus seem a little old-fashioned, and limiting. That said, the necessary features and functions all seem to be represented and easily accessible, so the interface serves its purpose.

File Storage

Google Docs provides 1GB of free storage. It doesn't sound like much, but there is a caveat--none of the files Icreate in Google Docs, or files I convert to Google Docs formats count against the quota. So, in essence the file storage is virtually unlimited, with an additional 1GB of storage for non-Google Docs data.

Above and beyond the file storage provided by Google itself, though, Google Docs is also closely integrated with Box--which provides 5GB of storage for free. I am going to dig into the online storage options separately later in the 30 Days With the Cloud series, but I do use Box so I appreciate the partnership.

Google Docs is the first of the three cloud-based suites I am checking out. Again, this is something that I will cover in more detail when I get into cloud storage, but Box lets me create new docs or spreadsheets with Google Docs right from the Box site. It is worth noting, however, that opening the files I already have stored on Box using Google Docs seems to be a complex process. If I click the option to edit a file from within Box, it actually uses Zoho Editor rather than Google Docs.

Compatibility

Google understands that it is important to be able to read from and save to the common Microsoft Office file formats. It has invested a significant amount of effort in working to maintain consistent formatting in converting the file back and forth.

The compatibility of Google Docs works fine with basic formatting, but the fidelity drops off quickly if I try to use advanced formatting features. Bold, italics, and underlining get converted without a problem, but if I have a document with tables, footnotes, a table of contents, or other formatting included, those things don't seem to translate well into Google Docs.

This is more important to some than others. Someone who regularly deals with Microsoft Office files from clients or suppliers, or someone who relies on advanced formatting features may not appreciate Google Docs. For my purposes, though, virtually everything I type into Word is simply copied and pasted into the PCWorld content publishing tool. I don't generally use fancy formatting, so Google Docs can meet my needs.

Sharing and Collaboration

This is the area where Google Docs really shines. It is simple for me to share files with other people and work on them together in real-time online. Google recently expanded the sharing and collaboration features to include Presentations, in addition to Documents and Spreadsheets.

I don't really use file sharing or real-time collaboration that much, but I do use it occasionally. When I do, it is almost always through Google Docs.

Mobile

Google Docs works fairly well on my iPhone and iPad. I was able to open a file from Google Docs and click Edit to modify the contents while in Mobile mode in the Safari browser on my iPad. Things did get wonky when I tried switching to Desktop mode using the link at the bottom of the page. I got error messages and it seemed to freak out every time I tried to type something.

Being a Google product, it makes sense that it works best with Android. My Google login is already associated with my Motorola Xoom tablet, and there is a native Google Docs app. When I open the app, it immediately displays my files. With Android, using Google Docs just works.

Overall, Google Docs seems to work for my purposes just fine. We'll see how Zoho and Microsoft stack up in the next couple days.


Online learning: Campus 2.0



When campus president Wallace Loh walked into Juan Uriagereka's office last August, he got right to the point. “We need courses for this thing — yesterday!”
Uriagereka, associate provost for faculty affairs at the University of Maryland in College Park, knew exactly what his boss meant. Campus administrators around the world had been buzzing for months about massive open online courses, or MOOCs: Internet-based teaching programmes designed to handle thousands of students simultaneously, in part using the tactics of social-networking websites. To supplement video lectures, much of the learning comes from online comments, questions and discussions. Participants even mark one another's tests.
MOOCs had exploded into the academic consciousness in summer 2011, when a free artificial-intelligence course offered by Stanford University in California attracted 160,000 students from around the world — 23,000 of whom finished it. Now, Coursera in Mountain View, California — one of the three researcher-led start-up companies actively developing MOOCs — was inviting the University of Maryland to submit up to five courses for broadcast on its software platform. Loh wanted in. “He was very clear,” says Uriagereka. “We needed to be a part of this.”
Similar conversations have been taking place at major universities around the world, as dozens — 74, at the last count — rush to sign up. Science, engineering and technology courses have been in the vanguard of the movement, but offerings in management, humanities and the arts are growing in popularity (see 'MOOCs rising'). “In 25 years of observing higher education, I've never seen anything move this fast,” says Mitchell Stevens, a sociologist at Stanford and one of the leaders of an ongoing, campus-wide discussion series known as Education's Digital Future.
The ferment is attributable in part to MOOCs hitting at exactly the right time. Bricks-and-mortar campuses are unlikely to keep up with the demand for advanced education: according to one widely quoted calculation, the world would have to construct more than four new 30,000-student universities per week to accommodate the children who will reach enrolment age by 2025 (seego.nature.com/mjuzhu), let alone the millions of adults looking for further education or career training. Colleges and universities are also under tremendous financial pressure, especially in the United States, where rocketing tuition fees and ever-expanding student debt have resulted in a backlash from politicians, parents and students demanding to know what their money is going towards.
When MOOCs came along, says Chris Dede, who studies educational technologies at Harvard University in Cambridge, Massachusetts, they promised to solve these problems by radically expanding the reach of existing campuses while streamlining the workload for educators — and universities seized on them as the next big thing.
There is reason to hope that this is a positive development, says Roy Pea, who heads a Stanford centre that studies how people use technology. MOOCs, which have incorporated decades of research on how students learn best, could free faculty members from the drudgery of repetitive introductory lectures. What's more, they can record online students' every mouse click, an ability that promises to transform education research by generating data that could improve teaching in the future. “We can have microanalytics on every paper, every test, right down to what media each student prefers,” says Pea.
MOOC companies still face challenges, such as dealing with low course-completion rates and proving that they can make profit. And they have a lot of convincing to do among faculty members, says Uriagereka. “Some salivate and can't wait to be a part of it,” he says, noting that his university had 20 volunteers for its 5 inaugural MOOCs. “Others say, 'Wait a minute. How do we preserve quality? How do we connect with students?'”

Large-scale pedagogy

MOOCs are largely a product of one corridor in the Stanford computer-science department, where the offices of Andrew Ng, Daphne Koller and Sebastian Thrun are just a few steps apart. But they are also the fruit of research dating back to at least the 1990s, when the explosive worldwide growth of the Internet inspired a multitude of efforts to exploit it for education. Campus administrators tended to regard such projects as a sideshow — the higher-education financial crunch was not quite as serious back then — so most experiments were the work of committed individuals, departments or research centres. But with the relentless advance of technologies such as broadband, social networking and smart phones, researchers' interest continued to grow.
Ng got involved in 2007 because he wanted to bring Stanford-quality teaching to “the people who would never be able to come to Stanford”, he says. Following a path blazed by the open-source software movement, and by earlier open-source education initiatives, he started a project to post online free lecture videos and handouts for ten of Stanford's most popular engineering courses. His approach was fairly crude, he admits: just record the lectures, put them online and hope for the best. But to his astonishment, strangers started coming up to him and saying, “Are you Professor Ng? I've been taking machine learning with you!” He began to grasp how far online courses could reach, and started working on a scaled-up version of his system. “When one professor can teach 50,000 people,” he says, “it alters the economics of education.”
One of the many people he talked to about his work was Koller, who began developing her own online-education system in 2009. Whereas Ng looked outwards, Koller wanted to look inwards and reform Stanford's teaching on-campus. She particularly wanted to promote 'flipping', a decade-old innovation in which students listen to lectures at home and do their 'homework' in class with their teachers, focusing on the most difficult aspects or discussing a concept's wider implications. This lets the instructors concentrate on the parts of teaching most of them enjoy — interacting with the students — and relieves them of the repetitive lecturing that they often dislike.
Koller also wanted to incorporate insights from the many studies showing that passively listening to a lecture is a terrible way to learn (F. I. M. Craik and R. S. Lockhart J. Verb. Learn. Verb. Behav. 11,671–684; 1972). Following an approach pioneered by other online developers over the previous decade, Koller broke each video into 8–10-minute segments separated by pauses in which students have to answer questions or solve a problem. The idea was to get them to think about what they had learned; the deeper their engagement, studies showed, the better their retention.
Finally, to encourage greater interaction among the students themselves, Koller took a cue from social-networking sites such as Facebook and gave her system an online discussion forum. As Ng explains, the idea was to extend what happens in a face-to-face study group: “Students sit with their best friends, they work on problems together, they critique each others' solutions — lots of pedagogical studies show that these more interactive modes of student engagement result in better student learning.”
Koller and Ng eventually realized that they could achieve both their goals — outreach and on-campus reform — by pooling their efforts. In late 2010, they started work on a software platform that would support discussion forums, video feeds and all the other basic services of an online course, so that an instructor only had to provide the content. But making social interaction work on a large scale turned out to be a research project of its own, says Ng. For example, standard online discussion forums are a fine way to bring communities together — for 100 or so users. “With 100,000 it gets more complicated,” he says. Hundreds of students might end up asking the same question. So the developers implemented a real-time search algorithm that would display related questions and potential answers before a student could finish typing. Ng and Koller also let students vote items up or down, much like on the link-sharing website Reddit, so that the most insightful questions would rise to the top rather than being lost in the chatter.
The two researchers even set the system up so that students could mark one another's homework for essay questions, which computers can't yet handle. Not only is such a system essential to scaling up learning, says Koller, but it also turns out to be a valuable learning experience. And experiments have shown that if the criteria are spelled out clearly, grades given by the students correlate strongly with those given by the teacher (R. Robinson Am. Biol. Teach. 63, 474–480; 2001).
By early 2011, Ng and Koller were planning to demonstrate the platform on campus, and other faculty members were paying attention. Among them was Thrun, a robotics researcher who was splitting his time between Stanford and Google in Mountain View, where he worked on the development of driverless cars.
It was Thrun's idea to go big, using a platform of his own based in part on Ng and Koller's ideas. He says that he was scheduled to teach an artificial-intelligence course that autumn, along with Peter Norvig, Google's director of research, “and I thought it was a social responsibility to take it online, so we could reach more than the 200 students we would get at Stanford”. But even he hadn't imagined how big it would get. This was the course that registered 160,000 people from 195 countries after just one public announcement, a post to an artificial-intelligence mailing list. “It shocked everybody,” he says.
In response, Ng took Koller's machine-learning course public using their platform, while department chair Jennifer Widom did the same with a database course. Each attracted roughly 60,000 students. With those numbers, venture-capital funding quickly followed.
Thrun announced his company Udacity in January 2012. Arguing that most professors don't have a clue about how to exploit the online medium, he and his colleagues elected to develop their courses in-house, working with education experts to make the pedagogy as effective as possible.
Ng and Koller announced Coursera in April 2012, and took the opposite tack. They partnered with big-name universities — Stanford and three others, to start — and let them provide the content while Coursera provided the hosting and software platform.
Anant Agarwal, former head of the computer science and artificial-intelligence laboratory at MIT, had been experimenting with online learning for a decade, developing an electric-circuit simulation package called WebSim that tried to give online students an effective substitute for hands-on laboratory experience. In December 2011, inspired by goings on at Stanford, he launched MITx: an independent, not-for-profit company that would offer massive online courses from MIT on an open-source basis. It became edX in May 2012, when Harvard joined.
At the same time, the term MOOCs, which had been circulating quietly in educational circles since it was coined in 2008, took off. Media accounts boomed, and company principals were soon giving talks at the popular Technology, Entertainment and Design (TED) conferences and the annual meeting of the World Economic Forum in Davos, Switzerland. As Koller told one interviewer: “I can't believe my life!”

Learning curve

The MOOC companies can point to plenty of success stories. For example, the 7,200 students who completed Agarwal's electric-circuits MOOC in spring 2012 included an 81-year-old man, a single mother with two children, and a 15-year-old prodigy from Mongolia who got a perfect score on the final exam. Udacity's Introduction to Computer Science MOOC, currently its most popular, has enrolled more than 270,000 students.
But MOOCs have also had some teething problems. “Many people have no idea what they're in for when they commit to put a course online,” says John Mitchell, a computer scientist and Stanford's first vice-provost of online learning. “Restructuring even one lecture into short, self-contained segments takes a fair amount of thinking.” So does coming up with good, compelling questions to engage the students between the segments. Then there is the push for high-quality production, he says. “It takes many hours to produce one hour of quality video.”
More worrisome are the MOOCs' dismal completion rates, which rarely rise above 15%. Completion has been a problem for distance learning ever since the first correspondence courses in the nineteenth century, says Dede. Only a small fraction of students have the drive and the perseverance to learn on their own, he says, and most people need help: “social support from their fellow students to help them keep going, and intellectual support from their professors and fellow students to help them figure out the material”. At the moment, says Dede, the MOOC companies' peer-to-peer communication tools don't do nearly enough to provide that kind of help. “They're just kind of hoping that people will figure out from the bottom up how to support each other,” he says.
The companies acknowledge that completion rates are a concern and that their platforms are still works in progress. “My aspiration isn't to reach the 1% of the world that is self-motivating,” says Thrun, “it's to reach the other 99%.” The companies are already working on enhanced social tools such as live video and text chat, for example.
And to observers such as David Krakauer, that is as it should be. “There are two ways to make something new,” says Krakauer, a biologist who directs the Institute for Discovery at the University of Wisconsin–Madison. “You can design something that's perfect on paper, and then try to build it. Or you can start with a system that's rubbish, experiment and build a better one with feedback. That's the Silicon Valley style — but it's also the scientific way.”

Silicon valley style

A Silicon Valley sensibility permeates the three big MOOC firms. For example, they all subscribe to the open-source ideal. “Charging for content would be a tragedy,” says Ng. But they also see plenty of opportunities to make money using the 'freemium' model followed by Google and many other technology companies: give away the basic product to draw users, and then charge for premium add-ons.
One obvious add-on might be certification, says Ng. “You would get a certificate that verifies you took the course for a small fee like US$10–$30” — a potentially substantial revenue stream when enrolments are in six figures. In the future, the companies might also offer full university course credits for a fee; they are already working with accreditation agencies to arrange that.
Other possibilities include profiting from in-course mentoring services, career counselling — and charging universities for licensing. In October 2012, for example, edX licensed a circuit-theory MOOC designed by Agarwal to San Jose State University in California, where it was used as the online component of a flipped classroom experience. In return for the licensing fee, “the professors can offer the course on campus, tweak the course however they please, get access to students' grades and online activity, and all the analytics a teacher would want to see”, says Agarwal. In this particular experiment, he adds, the San Jose course's usual 40% failure rate fell to 9%.
Analytics are another example of the Silicon Valley style, potentially allowing the MOOC companies to do for education what Internet giants such as Google or Amazon have done for marketing. In Coursera's case, says Koller, the platform monitors the students' every mouse click — “quiz submissions, forum posts, when and where a student pauses a lecture video, or rewinds, or moves to 1.5 speed”.
The company is constantly using these data as feedback, says Koller, both for refining the platform's user interface and for improving the course content. If 90% of the students start stumbling over the review exercises for a certain lecture, for example, then maybe it is time to revise that lecture.
“But anything we do is just the tip of the iceberg,” says Koller. When data from individual students are multiplied by tens or hundreds of thousands of students per course, they reach a scale big enough to launch a whole new field of learning informatics — “big-data science for education”, Pea calls it.
Learning informatics could provide an unprecedented level of feedback for colleges and universities, says Stevens: “We haven't measured learning in higher education very often, very consistently or very well — ever.” Academics have endlessly studied factors that are associated with university enrolment and success, such as race, parental income and school achievement. They have also studied what happens after graduation: the higher earnings and other benefits that college confers, on average, over a lifetime.
“What we don't know is how college performs this magic,” says Stevens. “We certainly don't know the extent to which digitally mediated college experiences will deliver the same returns as a four-year residential experience.” Now, however, he and his colleagues can begin to see what education science will look like as it merges with data analytics. Instead of looking at aggregate data about students on average, for example, researchers can finally — with appropriate permissions and privacy safeguards — follow individual students throughout their university careers, measuring exactly how specific experiences and interactions affect their learning. “It's thrilling,” he says, “a huge intellectual frontier.”
What remains to be seen is how higher education will change in response to the new technology. Maybe not much, says Dede. Yes, the major universities will extend their courses beyond their own campuses; the MOOCs have already shown them that they can do so with relatively little effort and potentially large profits. But the MOOC founders' other goal — fundamental reform in on-campus teaching — is a much tougher proposition.
“Universities think of themselves as being in the university business, not the learning business,” explains Dede. That is, they mostly take their existing structures and practices as given, and look to MOOCs and other online technologies as a way to do things more cheaply. But experience with earlier innovations such as personal computing shows the limits of that approach, he says: real gains in the productivity and effectiveness of learning will not come until universities radically reshape those structures and practices to take full advantage of the technology.
No one knows exactly where that restructuring might end up. Lectures becoming a rarity, for example? Vast numbers of students getting their degrees entirely online? But the revolution has already begun, says Stevens. Major universities such as Stanford are taking the lead, “trying to integrate and embed digital learning into the fabric of the entire university” — and trying to master the new technology before it masters them.
Virtually everyone participating in this upheaval agrees on one thing. Colleges and universities will change — perhaps dramatically — but they will not disappear. “No one says that all education has to be online,” says Thrun. “Sometimes, a classroom is better.” Especially in communal endeavours such as science, “education is more than just knowledge”, says Dede. “It's abilities like leadership and collaboration, and traits like tenacity”, all of which are best learned face to face.
An unspoken irony weaves through almost every discussion about MOOCs: thanks to innovations such as flipping, online technology's most profound effect on education may be to make human interaction more important than ever. As Krakauer puts it, “what's absolutely clear is that the very large lecture hall can be completely replaced: there's no value added over watching it at home on an iPad screen with a cup of tea. But there is also no substitute for a conversation.”






Wednesday, 13 March 2013

5 Trends That Will Drive The Future Of Technology



Trends get a bad rap, mostly because they are often equated with fashions. Talk about trends and people immediately start imagining wafer thin models strutting down catwalks in outrageous outfits, or maybe a new shade of purple that will be long forgotten by next season.

Yet trends can be important, especially those long in the making. If lots of smart people are willing to spend years of their lives and millions (if not billions) of dollars on an idea, there’s probably something to it.

Today, we’re on the brink of a new digital paradigm, where the capabilities of our technology are beginning to outstrip our own. Computers are deciding which products to stock on shelves, performing legal discovery and even winning game shows. They will soon be driving our cars and making medical diagnoses. Here are five trends that are driving it all.


1. No-Touch Interfaces


We’ve gotten used to the idea that computers are machines that we operate with our hands. Just as we Gen Xers became comfortable with keyboards and mouses, Today’s millennial generation has learned to text at blazing speed. Each new iteration of technology has required new skills to use it proficiently


That’s why the new trend towards no-touch interfaces is so fundamentally different. From Microsoft’s Kinect to Apple’s Siri to Google’s Project Glass, we’re beginning to expect that computers adapt to us rather than the other way around.

The basic pattern recognition technology has been advancing for generations and, thanks to accelerating returns, we can expect computer interfaces to become almost indistinguishable from humans in little more than a decade.

2. Native Content

While over the past several years technology has become more local, social and mobile, the new digital battlefield will be fought in the living room, with Netflix, Amazon, Microsoft, Google, Apple and the cable companies all vying to produce a dominant model for delivering consumer entertainment.
One emerging strategy is to develop original programming in order to attract and maintain a subscriber base. Netflix recently found success with their “House of Cards” series starring Kevin Spacey and Robin Wright. Amazon and Microsoft quickly announced their own forays into original content soon after.
Interestingly, HBO, which pioneered the strategy, has been applying the trend in reverse. Their HBO GO app, which at the moment requires a cable subscription, could easily be untethered and become a direct competitor to Netflix.

3. Massively Online


In the last decade, massively multiplayer online games such as World of Warcraft became all the rage. Rather than simply play against the computer, you could play with thousands of others in real time. It can be incredibly engrossing (albeit a bit unsettling when you realize that the vicious barbarian you’ve been marauding around with is actually a 14 year-old girl).

Now other facets of life are going massively online. Khan Academy offers thousands of modules for school age kids, Code Academy can teach a variety of programming languages to just about anybody and the latest iteration is Massively Online Open Courses (MOOC’s) that offer university level instruction. (For a good example, see here).

The massively online trend has even invaded politics, with President Obama recently reaching out to ordinary voters through Ask Me Anything on Reddit and Google Hangouts.

4. The Web of Things


Probably the most pervasive trend is the Web of Things, where just about everything we interact with becomes a computable entity. Our homes, our cars and even objects on the street will interact with our smartphones and with each other, seamlessly.

What will drive the trend in the years to come are two complementary technologies: Near Field Communication (NFC), which allows for two-way data communication with nearby devices and ultra-low power chips that can harvest energy in the environment, which will put computable entities just about everywhere you can think of.

While the Web of Things is already underway, it’s difficult to see where it will lead us. Some applications, such as mobile payments and IBM’s Smarter Planet initiative, will become widespread in just a few years. Marketing will also be transformed, as consumers will be able to seamless access digital products from advertisements in the physical world.

Still, as computing ceases to be something we do seated at a desk and becomes a natural, normal way of interacting with our environment, there’s really no telling what the impact will be.

5. Consumer Driven Supercomputing


Everybody knows the frustration of calling to a customer service line and having to deal with an automated interface. They work well enough, but it takes some effort. After repeating yourself a few times, you find yourself wishing that you can just punch your answers in or talk to someone at one of those offshore centers with heavy accents.

Therein lies the next great challenge of computing. While we used to wait for our desktop computers to process our commands and then lingered for what seemed like an eternity for web pages to load, we now struggle with natural language interfaces that just can’t quite work like we’d like them to.

Welcome to the next phase of computing. As I previously wrote in Forbes, companies ranging from IBM to Google to Microsoft are racing to combine natural language processing with huge Big Data systems in the cloud that we can access from anywhere.

These systems will know us better than our best friends, but will also be connected to the entire Web of Things as well as the collective sum of all human knowledge. The first of these, IBM’s Watson, costs $3 million to build, but that price will drop to about $30,000 in ten years, well within the reach of most organizations.

When Computers Disappear

When computers first appeared, they took up whole rooms and required specialized training to operate them. Then they arrived in our homes and were simple enough for teenagers to become proficient in their use within a few days (although adults tended to be a little slower). Today, my three year old daughter plays with her iPad as naturally as she plays with her dolls.

Now, computers themselves are disappearing. They’re embedded invisibly into the Web of Things, into no-touch interfaces and into our daily lives. While we’ve long left behind loading disks into slots to get our computers to work and become used to software as a service – hardware as a service is right around the corner.

That’s why technology companies are becoming a increasingly consumer driven, investing in things like native content to get us onboard their platform, from which we will sign onto massively online services to entertain and educate ourselves.

The future of technology is, ironically, all too human.


Advanced Threats: See Them...Stop Them


ARBOR NETWORKS :: SMART. AVAILABLE. SECURE.

Webinar

Advanced Threats: Why You Have to See It to Protect It
The threat landscape has evolved dramatically over the last few years -- DDoS threats combining with data exfiltration and corporate espionage reveal new dangers.
How can security professionals expect to stop the threat if they can't see it?
Join us for an informative webinar as we discuss:

  • The need for increased visibility inside the network where hidden malware may lurk
  • Types of threats that enterprises and providers are seeing in their networks today
  • How to detect and stop advanced threats
  • Why legacy security solutions were not designed to protect against advanced threats
Can't make the date? All registrants will have access to the on-demand webinar replay, so register today!
Register

Advanced Threats: Why You Have to See It to Protect It

Date:
Thursday, March 14, 2013

Time:
11:00 a.m. EST | 8:00 a.m. PST

Featured Presenters:
Rakesh Shah
Senior Director
Product Marketing and Strategy
Arbor Networks, Inc.
Michael Suby
Analyst
Stratecast




Saturday, 9 March 2013

Try F# - A New Wave of Education and Research



The 2013 release of Try F# demonstrates the power of F# to solve real-world analytical programming and information-rich problems by providing a web experience to help you learn the F# language, create programs, and share information—quickly and easily. Learn how students at University College London are using Try F# to develop solutions to real-world problems for the financial industry. And hear how Try F# helps undergraduates and graduate students alike learn F# and develop F# programs that use big data at Rensselaer Polytechnic Institute.

  • Learn: Easily learn the fundamentals and tap into the power of F# programming.
  • Create: Start coding within Try F#, which enables you to write F# code in your browser and save your program to the cloud.
  • Share: Share your code with others via Twitter or Facebook, or simply send them a link to your Try F# script file. 


Get Microsoft Silverlight

Friday, 8 March 2013

Microsoft Is Talking About the Future, a Lot



Perceptive Pixel's screens look like the offspring of an iPad and a television set.
Ted S. Warren/Associated Press Perceptive Pixel’s screens look like the offspring of an iPad and a television set.

There are technology companies that won’t say anything about the futuristic inventions they’re tinkering with in their labs — Apple, for instance.

Then there are the companies that won’t stop talking about them. Think Google and its driverless cars and Google Glass.

Microsoft is firmly in the latter camp. The company says it has the largest research organization of its kind and is a prolific publisher of academic-style papers, which it shares openly. For years it has operated a home of the future in a building on its campus where it invites visitors for a glimpse of how technology could reshape kitchens, living rooms and bedrooms years from now.

Earlier this week, it held an annual event for a small group of journalists inside its home of the future, recently remodeled to include more examples of what workplaces of the future might look like. One technology
Microsoft returned to again and again in its demonstrations was jumbo-size touchscreens, which are based on designs by Perceptive Pixel, a company Microsoft acquired last year. Perceptive Pixel’s screens, which look like the offspring of an iPad and a television set, are most familiar to people who have watched election night coverage on networks like CNN, where on-air commentators have for years manipulated electoral maps using the technology.

Microsoft believes the technology will have a big impact on offices, where they will replace whiteboards, allow for more immersive video conferences and transform the way presentations are delivered. Microsoft showed one research project that used the displays in which a presenter could revamp charts and bar graphs on the fly with different data by using a stylus to sketch little codes on the screen.

“It changes the way meetings work,” said Rick Rashid, Microsoft’s chief research officer.

The company is using the technology widely in-house now, a process known in the tech industry as “dogfooding.” Its chief executive, Steve Ballmer, has a giant touch-screen in his office, as do a number of other senior executives. Some meeting spaces at Microsoft are being redesigned to be more open so they can accommodate the giant screens, which can be bigger than 80 inches.

“It won’t be unreasonable to think of all walls being touch-enabled,” said Kurt Delbene, president of the Office division at Microsoft, who said Microsoft would bring the cost of the devices down “substantially” from the tens of thousands of dollars that bigger ones cost today.

Microsoft talks a lot more than Apple does about projects like giant touchscreens partly because it thinks it can spark wider interest and investment in categories that will come back to benefit the company, as a major provider of software and services for computers. Apple, in contrast, says almost nothing about the technologies it is working on until shortly before they can be purchased as products in a store, the better to maximize sales.

It’s also worth mentioning that Microsoft far outspends Apple on research and development, devoting nearly $10 billion, or close to 13 percent of revenue, in its most recent fiscal year (the vast majority of this figure stems from development costs, rather than pure research). Last year Apple spent $3.4 billion, or 2 percent of its revenue, on research and development.

Apple appears to have gotten a lot more out of a far smaller investment than Microsoft has. But whatever their research investments, it’s tough to overstate how Apple has out-executed Microsoft over the past five years in creating compelling mobile products like tablets and smartphones. Microsoft was in both categories long before its rival, but fumbled its leads there.

Mr. Rashid said Microsoft’s hefty investments in research, especially basic technology research that may not yield products for years or ever, are essential for its future. He said the technology industry was littered with companies that didn’t invest enough in long-term research, only to run into trouble when technology trends shifted.

“It gives you the ability to survive if things go wrong,” he said.


Monday, 4 March 2013

Virtualization 101



There are a number of emerging and proposed standard protocols focused on optimizing the support that data center Ethernet LANs provide for server virtualization. Several of these protocols are aimed at network virtualization via the creation of multiple virtual Ethernet networks that can share a common physical infrastructure in a manner that is somewhat analogous to multiple virtual machines sharing a common physical server.

Most protocols for network virtualization are based on creating virtual network overlays using techniques based on encapsulation and tunneling. The most commonly discussed protocols include VXLAN, NVGRE, STT, and SPB MAC-in-MAC. SPB is already an IEEE standard, while it is likely that only one of the other proposals will achieve IETF standard status, most likely VXLAN.

Traditional network virtualization

The one-to-many virtualization of network entities is not a new concept. The most common examples are VLANs and Virtual Routing and Forwarding (VRF) instances.

VLANs partition the network into as many as 4,094 broadcast domains, as designated by a 12-bit VLAN ID tag in the Ethernet header. VLANs have been a convenient means of isolating different types of traffic that share the same switched LAN infrastructure.

In data centers that make extensive use of server virtualization, the limited number of VLANs can present problems, especially when large number of tenants need to be supported, each requiring multiple VLANs. Extending VLANs across the data center via 802.1Q trunks to support VM mobility adds operational cost and complexity. In data centers based on Layer 2 server-to-server connectivity, large numbers of VMs, each with its own media access control address, can also place a burden on the forwarding tables capacities of Layer 2 switches.
Virtualization

VRF is a form of Layer 3 network virtualization in which a physical router supports multiple virtual router instances, each running its own routing protocol instance and maintaining its own forwarding table.
Unlike VLANs, VRF does not use a tag in the packet header to designate the specific VRF to which a packet belongs. The appropriate VRF is derived at each hop based both on the incoming interface and on information in the frame. An additional requirement is that each intermediate router on the end-to-end path followed by a packet needs to be configured with a VRF instance that can forward that packet.




Network Virtualization with Overlays

Because of the shortcomings of the traditional VLAN or VRF models, a number of new techniques for creating virtual networks have recently emerged. Most are based on the use of encapsulation and tunneling to construct multiple virtual network topologies overlaid on a common physical network.

A virtual network can be a Layer 2 network or a Layer 3 network, while the physical network can be Layer 2, Layer 3 or a combination depending on the overlay technology. With overlays, the outer (encapsulating) header includes a field that is generally 24 bits wide that carries a virtual network instance ID (VNID) that specifies the virtual network designated to forward the packet.


Virtual network overlays can provide a wide range of benefits, including:


• Support for essentially unlimited numbers of virtual networks; for example the 24-bit header enables the creation of up to 16 million virtual networks.
• Decoupling of the virtual network topology, service category (L2 or L3) and addressing from those of the physical network. The decoupling avoids issues such as MAC table size in physical switches.
• Support for virtual machine mobility independent of the physical network. If a VM changes location, even to a new subnet, the switches at the edge of the overlay simply update their mapping tables to reflect the new location of the VM. The network for a new VM can be provisioned entirely at the edge of the network.
• Ability to manage overlapping IP addresses between multiple tenants.
• Support for multi-path forwarding within virtual networks

The main difference between the various overlay protocols lies in their encapsulation formats and the control plane functionality that allows ingress (encapsulating) devices to map a frame to the appropriate egress (decapsulating) device.

VXLAN

Virtual eXtensible LAN (VXLAN) virtualizes the network by creating a Layer 2 overlay on a Layer 3 network via MAC-in-UDP encapsulation. The VXLAN segment is a Layer 3 construct that replaces the VLAN as the mechanism that segments the data center LAN for VMs.

Therefore, a VM can only communicate or migrate within a VXLAN segment. The VXLAN segment has a 24-bit VXLAN Network identifier. VXLAN is transparent to the VM, which still communicates using MAC addresses. The VXLAN encapsulation is performed through a function known as the VXLAN Tunnel End Point (VTEP), typically provided by a hypervisor switch or a possibly a physical access switch.

The encapsulation allows Layer 2 communications with any end points that are within the same VXLAN segment, even if these end points are in a different IP subnet. This allows live migrations of VMs to transcend Layer 3 boundaries. Since MAC frames are encapsulated within IP packets, there is no need for the individual Layer 2 switches to learn MAC addresses.

This alleviates MAC table hardware capacity issues on these switches. Overlapping IP and MAC addresses are handled by the VXLAN ID, which acts as a qualifier/identifier for the specific VXLAN segment within which those addresses are valid. The VXLAN control solution uses flooding based on Any Source Multicast (ASM) to disseminate end system location information.

As noted, VXLAN uses a MAC-in-UDP encapsulation. One of the reasons for this is that modern Layer 3 devices parse the 5-tuple (including Layer 4 source and destination ports). While VXLAN uses a well-known destination UDP port, the source UDP port can be any value. As a result, a VTEP can spread all the flows from a single VM across many UDP source ports. This allows the intermediate Layer 3 switches to make efficient use of multi-pathing even in the case of multiple flows between only two VMs.

Where VXLAN nodes on a VXLAN overlay network need to communicate with nodes on a legacy (i.e., VLAN) portion of the network, a VXLAN gateway can be used to perform the required tunnel termination functions including encapsulation/decapsulation. The gateway functionality could be implemented in either hardware or software.


VXLAN is the subject of a IETF draft supported by VMware, Cisco, Arista Networks, Broadcom, Red Hat and Citrix. VXLAN is also supported by IBM. Pre-standard implementations in hypervisor vSwitches and physical switches are beginning to emerge.

NVGRE

Network Virtualization using Generic Router Encapsulation (NVGRE) uses the GRE tunneling protocol defined by RFC 2784 and RFC 2890. NVGRE is similar in most respects to VXLAN with two major exceptions. While GRE encapsulation is not new, most network devices do not parse GRE headers in hardware, which may lead to performance issues and issues with 5-tuple hashes for traffic distribution in multi-path data center LANs.

The other exception is that the current IETF NVGRE draft does not specify a solution for the control plane functionality described earlier in general description of Network Overlays, leaving that for a future draft or possibly as something to be addressed by SDN (Software Defined Networking) controllers.

Some of the sponsors of NVGRE (i.e., Microsoft and Emulex) expect that some of the performance issues can be addressed by intelligent network interface cards (NIC) that offload NVGRE endpoint processing from the hypervisor vSwitch. The intelligent NICs would also have APIs for integration with overlay controllers and hypervisor management systems. Emulex has also demonstrated intelligent NICs that offload VXLAN processing from the VMware Distributed Switches.

STT

Stateless Transport Tunneling (STT) is a third overlay technology for creating Layer 2 virtual networks over a Layer 2/Layer 3 physical network within the data center. Conceptually, there are a number of similarities between VXLAN and STT. The tunnel endpoints are typically provided by hypervisor vSwitches, the VNID is 24 bits wide, and the transport source header is manipulated to take advantage of multi-pathing.

STT encapsulation differs from NVGRE and VXLAN in two ways. First, it uses a stateless TCP-like header inside the IP header that allows tunnel endpoints within end systems to take advantage of TCP segmentation offload (TSO) capabilities of existing TCP offload engines (TOE) that reside on server NICs.

The benefits to the host include lower CPU utilization and higher utilization of 10Gigabit Ethernet access links. STT also allocates more header space to the per-packet metadata, which provides added flexibility for the virtual network control plane. With these features, STT is optimized for hypervisor vSwitches as the encapsulation/decapsulation tunnel endpoints.

The STT IETF draft sponsored by Nicira does not specify a control plane solution. However, the Nicira network virtualization solution includes OpenFlow-like hypervisor vSwitches and a control plane based on a centralized network virtualization controller that facilitates management of virtual networks.

Shortest Path Bridging MAC-in-MAC (SPBM)

IEEE 802.1aq SPBM uses IEEE 802.1ah MAC-in-MAC encapsulation and the IS-IS routing protocol to provide Layer 2 network virtualization via VLAN extension in addition to the loop-free equal cost multi-path Layer 2 forwarding functionality normally associated with SPB.

VLAN extension is enabled by the 24 bit Virtual Service Network (VSN) Instance Service IDs (I-SID) that are part of the outer MAC encapsulation. Unlike other network virtualization solutions, no changes are required in the hypervisor vSwitches or NICs and switching hardware already exists that supports IEEE 802.1ah MAC-in-MAC encapsulation. For SPBM, the control plane is provided by the IS-IS routing protocol.

SPBM can also be extended to support Layer 3 forwarding and Layer 3 virtualization as described in the IP/SPB IETF draft using IP encapsulated within the outer SPBM MAC. This draft specifies how SPBM nodes can perform Inter-ISID or inter-VLAN routing. In addition, IP/SPB also provides for Layer 3 VSNs by extending Virtual Routing and Forwarding (VRF) instances at the edge of the network across the SPBM network without requiring that the core switches also support VRF instances.

VLAN-extension VSNs and VRF-extension VSNs can run in parallel on the same SPB network to provide isolation of both Layer 2 and Layer 3 traffic for multi-tenant environments. With SPBM, all the core switches starting at the access or aggregation switches that define the SPBM boundary need to be SPBM-capable. SPBM hardware switches are currently available from Avaya and Alcatel-Lucent.

Alternative solutions

A discussion of network virtualization would not be complete without at least a mention of two Cisco protocols: Overlay Transport Virtualization (OTV) and Locator/ID Separation Protocol (LISP).
OTV is optimized for inter-data center VLAN extension over the WAN or Internet using MAC-in-IP encapsulation. It prevents flooding of unknown destinations across the WAN by advertising MAC address reachability using IS-IS routing protocol extensions.

LISP is an encapsulating IP-in-IP technology that allows end systems to keep their IP address (ID) even as they move to a different subnet within the network (Location). By using LISP VM-Mobility, IP endpoints such as VMs can be relocated anywhere regardless of their IP addresses while maintaining direct path routing of client traffic. LISP also supports multi-tenant environments with Layer 3 virtual networks created by mapping VRFs to LISP instance-IDs.

In addition, future versions of the OpenFlow protocol will undoubtedly support some standards-based overlay functionality. In the interim, OpenFlow can potentially provide another type of network virtualization by isolating network traffic based on segregating flows. One very simple way to do this is to isolate sets of MAC addresses without relying on VLANs by adding a filtering layer to the OpenFlow controller. This type of functionality is available in v0.85 of the Big Switch Networks Floodlight controller. In multi-tenant environments there is also the potential for the OpenFlow controller to support a separate controller instance for each tenant.

Summary

The IT industry is in a state of dramatic flux. One of the primary technology drivers of this flux is the ongoing adoption of virtualization that started with server virtualization and is just now impacting the network. There are many technologies and techniques that IT organizations can use to implement network virtualization. This includes two Cisco protocols: Overlay Transport Virtualization and the Locator/ID Separation Protocol. It also includes a number of emerging technologies based on encapsulation and tunneling; e.g., VXLAN. In addition, the interest that IT organizations have in SDN is starting to accelerate. Network virtualization is one 
of the primary use cases that are associated with SDN.