This article titled “Amazon outage hits Quora and others” was written by Charles Arthur, for guardian.co.uk on Thursday 21st April 2011 19.25 Asia/Calcutta

Sites including answer service Quora, news service Reddit, Hootsuite and location tracker FourSquare have been affected by outages at Amazon’s cloud computing centre in North Virginia, which they rely on to provide their service.

Quora was unreachable in the UK on Thursday morning and afternoon. The site is entirely hosted on Amazon’s EC2 (Elastic Cloud Computing) service, as are FourSquare and a number of other services. Hootsuite’s response was slow, while Reddit’s search service was out of action, announcing: “Amazon is currently experiencing a degradation. They are working on it.”

Amazon’s cloud computing status page currently shows problems at the North Virginia centre, which provides services for a number of Web 2.0 companies. The disruption started at about 1.40am on the US West Coast, or 9.40am BST, and have continued since then.

Many web-based companies, especially startups, use cloud computing services from companies including Amazon, Google and Microsoft. They are charged only for the computing power that is used, rather than having to make expensive capital investments in servers which could rendered undersized in a few months by the rapid growth that they often aim to achieve.

Amazon hasn’t given any specific time by which the problem will be fixed.

The North Virginia site is one of many cloud computing centres run by Amazon, but such systems are usually designed so that an outage in one centre does not disrupt others – nor the clients using the service. Amazon has not offered any reason why the problems at North Virginia have not been routed around and the load redistributed to its many other centres.

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This article titled “Alternatives to Bloglines” was written by Jack Schofield, for guardian.co.uk on Thursday 28th October 2010 18.37 Asia/Calcutta

As the Bloglines RSS aggregator is closing at the end of the month, could you recommended another web-based RSS reader? I don’t particularly want to use Google Reader if there is a suitable alternative.
David Dixon

In a blog post, Ask.com says it is closing Bloglines on 1 November, and that “being locked in an RSS reader makes less and less sense to people as Twitter and Facebook dominate real-time information flow. Today RSS is the enabling technology – the infrastructure, the delivery system. RSS is a means to an end, not a consumer experience in and of itself. As a result, RSS aggregator usage has slowed significantly, and Bloglines isn’t the only service to feel the impact. The writing is on the wall.”

This is true, but it’s not the whole story. First, in 2005, Ask.com bought Bloglines and Google launched Reader, and at that point, Bloglines was much better. Since then, Google Reader has been redesigned twice and got much better, while Bloglines hasn’t – the new Bloglines Beta went nowhere. Second, people have many other ways to consume RSS (Really Simple Syndication) feeds from websites. These range from powerful but complicated online services such as Netvibes (of which iGoogle is basically a knock-off) to simple email clients such as Microsoft’s Windows Live Hotmail (the desktop version).

The “line of least resistance” now leads from Bloglines to Google Reader, because most people already have a Google account. When you are logged into one Google service, Google Reader is just a pull-down menu option from the Google home page. And my warnings about putting too many eggs in the same basket – where you risk losing your data if your account is hacked or blocked – don’t apply to RSS feeds.

But although it looks as though the web-based reader market is closing down, leaving Google Reader with total market domination, there are still a few alternatives. If you like Bloglines’ relatively simplistic approach, for example, have a look at FastLadder, or possibly the beta version of FeedShow.

Nonetheless, the main market trends are to combine RSS webfeeds with feeds from social networking sites such as Facebook and Twitter, and to display the results in a more magazine-style format. If you fancy that kind of thing, try Activorus. (Feedly also takes that approach, but in a Firefox browser window.)

One of the benefits of reading RSS feeds is that they provide lightweight versions of stories without all the website’s furniture such as logos, widgets and navigation systems. Full RSS feeds mean you no longer have to go to the website and wait while your browser downloads JavaScript code, Flash and Java applets, large photos and other mostly-pointless rubbish. However, Feedlooks – which is still in beta – has now “reinvented” feed reading by letting you “read content in full visual glory without leaving the app”. Feedlooks looks like a basic feed reader (with a built-in Twitter client), but when you click on a link, it shows the original story from the web site. You can try it for an hour without creating an account.

Finally, for real geeks who think Bloglines was much too ponderous, there’s the open source Tiny Tiny RSS project. You can set it up on your own server (it requires PHP, MySQL, etc), which is the least transitory option. Unfortunately, the Tiny Tiny RSS demo site is no longer accepting new users, but you can hunt around for ones that people have set up on free servers.

As I’m sure you know, the key to trying different RSS readers is OPML (Outline Processor Markup Language), an XML format for outlines originally developed by Dave Winer for Radio UserLand. Before Bloglines closes, all users should click on Feeds, then choose “Export Subscriptions” and save the resulting OPML file. Your alternative RSS reader should be able to import it.

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This article titled “How do we counter cyber attack? That’s the £500m question” was written by John Naughton, for The Observer on Sunday 31st October 2010 04.45 Asia/Calcutta

The news that, according to the national security review at least, cyber attack comes second only to terrorism as the gravest security threat facing the nation will have come as a great surprise to most citizens. We are conscious of the annoyances of malware, viruses, worms, spam and phishing, but for most these are just minor irritations, not threats to the nation’s survival.

Yet the other day we had the foreign secretary gravely intoning why, in the midst of the most savage spending cuts in living memory, it is suddenly necessary to give an extra £500m to GCHQ to protect us against nemesis in cyberspace. At the same time, in America, we see the Pentagon setting up a whole new cyber command, USCybercom, with all the usual paraphernalia and awash with funding.

What, you might ask, is going on?

There seem to be two broad answers to the question. The cynical one is that this is just the latest development of the military-industrial complex that is the bane of industrialised economies. Changes in society and warfare patterns threaten the future prosperity of this colossal set of vested interests.

Aircraft carriers, missile systems and tanks are of little use against ragged-trousered terrorists and so a new and sinister threat has to be manufactured to ensure reliable cash-flow for BAE Systems & co into the next century. In which case, cyber security will do nicely.

And, say the cynics, the strategy is succeeding. According to the New Yorker journalist Seymour Hersh, the military-industrial complex in the US has morphed into “a military-cyber complex”. Hersh says that the US government spends between bn and bn annually for unclassified cyber-security work and about the same on the classified part.

The alternative explanation is that the threat really is more serious than many of us had supposed. The arrival of the Stuxnet worm was a salutary event because of its sophistication and the fact that it targeted a device that plays a critical role in innumerable industrial processes. Could it be that the threat truly has ratcheted up? Is there a real threat of “cyber warfare”? If so, what could be done about it?

At a seminar in Cambridge last week, Dr Herbert Lin of the National Academies of the USA gave a sobering overview of the challenges posed by conflict in cyberspace. The central problem is that, in the online domain, the attacker has most of the advantages. Passive defences (better firewalls, anti-virus precautions etc) can have some effect, but they’re never going to deter or prevent determined or sophisticated attacks.

So what does a nation do?

One answer is to seek lessons from the policy of nuclear deterrence. Many policy-makers see cyber deterrence as the only feasible policy in an offence-dominated domain. After all, we have lots of experience with nuclear deterrence and we know it worked. So maybe that’s the way to go?

Alas, no. As Dr Lin put it, while nuclear and cyber deterrence raise the same questions, the answers are different and much less satisfactory in the online case. Deterrence is a tool for dissuading an adversary from taking hostile action, but it depends on being able to identify the potential attacker. Nuclear deterrence worked for various reasons: only nation-states were potential adversaries; attacks would have been easy to detect and would have come from outside one’s territorial boundaries. It was possible to demonstrate that one possessed the capability for devastating retaliation and it would have been easy to determine when hostilities had ceased.

None of this applies in cyberspace. The resources to mount attacks are not the sole prerogative of nation-states. It may be difficult to distinguish an attack from incessant malware and cybercrime. Identifying the source of an attack can be problematic and an astute attacker might leave a false trail leading to a country that would regard massive retaliation as an act of war. There’s no obvious way of demonstrating a capability for retaliation. There’s no precedent for countries targeting nuclear strikes on companies. And there’s no obvious way of establishing that hostilities have definitively ceased.

The inescapable conclusion is that deterrence won’t work in cyberspace. We need a better idea. The £500m we’ve just donated to GCHQ suggests that it won’t come cheap.

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This article titled “HTML5 facts and myths: a Javascript expert and Opera evangelist explain” was written by Charles Arthur, for guardian.co.uk on Friday 24th September 2010 17.45 Asia/Calcutta

Does HTML5 seem like this to you? Photo by ianmyles on Flickr. Some rights reserved

For lunchtime reading (and cramming), Smashing Magazine has a very good introduction to HTML5 – specifically, as it puts it, the facts and the myths.

As the article says,

“Everyone’s talking about HTML5. it’s perhaps the most hyped technology since people started putting rounded corners on everything and using unnecessary gradients. In fact, a lot of what people call HTML5 is actually just old-fashioned DHTML or AJAX. Mixed in with all the information is a lot of misinformation, so here, JavaScript expert Remy Sharp and Opera’s Bruce Lawson look at some of the myths and sort the truth from the common misconceptions.”

The facts are useful (basically, a history of where HTML5 came from), and rather than shamefully ripping off their content we’ll just give you the bullet points from the section they call…

The Myths

• “I Can’t Use HTML5 Until 2012 (or 2022)”
(We’ve heard this one a few times in the comments around here. Ain’t so.)

• “My Browser Supports HTML5, but Yours Doesn’t”
(Willy-waving doesn’t make sense in the browser camp.)

• HTML5 Legalizes Tag Soup
(No, though it relaxes some things – no more searching for that missing />)

• “I Need to Convert My XHTML Website to HTML5″
(Nope, XHTML is a finished spec.)

• HTML5 Kills XML
(Not at all.)

• HTML5 Will Kill Flash and Plug-Ins
Actually, because this is perhaps one of the most contentious issues, we’ll quote what they say almost in full:

“Just as when CSS Web fonts weren’t widely supported and Flash was used in sIFR to fill the gaps, Flash also saves the day by making HTML5 video backwards-compatible. Because HTML5 is designed to be “fake-able” in older browsers, the mark-up between the video tags is ignored by browsers that understand HTML5 and is rendered by older browsers. Therefore, embedding fall-back video with Flash is possible using the old-school <object> or <embed> tags, as pioneered by Kroc Camen is his article “Video for Everybody!”.

“But not all of Flash’s use cases are usurped by HTML5. There is no way to do digital rights management in HTML5; browsers such as Opera, Firefox and Chrome allow visitors to save video to their machines with a click of the context menu. If you need to prevent video from being saved, you’ll need to use plug-ins.”

• HTML5 Is Bad for Accessibility
(It doesn’t have to be, though the <canvas> tag can be a problem; blame it on Apple.)

• “An HTML5 Guru Will Hold My Hand as I Do It the First Time”
(No, though there are already boilerplates that you can use. Just rejoice.)

Now you’ve got this far, you can go and read the article.

There’s also a video talk that Lawson gave at the 2009 OSCON conference on, yes, HTML5: the subject being “A pragmatic look at HTML 5 by experimenting with converting a real site to HTML 5 – how does it work? Where it useful and where is it annoying? How is support in current browsers?”

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A heat map is a graphical representation of data where the values taken by a variable in a two-dimensional map are represented as colors. A very similar presentation form is a tree map. The term is also used to mean its thematic application as a choropleth map.

Heat maps originated in 2D displays of the values in a data matrix. Larger values were represented by small dark gray or black squares (pixels) and smaller values by lighter squares. Sneath (1957) displayed the results of a cluster analysis by permuting the rows and the columns of
a matrix to place similar values near each other according to the clustering. Jacques Bertin used a similar representation to display data that conformed to a Guttman scale. The idea for joining cluster trees to the rows and columns of the data matrix originated with Robert Ling in 1973. Ling used overstruck printer characters to represent different shades of gray, one character-width per pixel. Leland Wilkinson developed the first computer program in 1994 (SYSTAT) to produce cluster heat maps with high-resolution color graphics. The Eisen et al. display shown in the figure is a replication of the earlier SYSTAT design.

There are several different kinds of heat map:

• Web heat maps have been used for displaying areas of a Web page most frequently scanned by visitors.
• Biology heat maps are typically used in molecular biology to represent the level of expression of many genes across a number of comparable samples (e.g. cells in different states, samples from different patients) as they are obtained from DNA microarrays.
• The tree map is a 2D hierarchical partitioning of data that visually resembles a heat map.
  A mosaic plot is a tiled heat map for representing a two-way or higher-way table of data. As with treemaps, the rectangular regions in a mosaic plot are hierarchically organized. The means that the regions are rectangles instead of squares. Friendly (1994) surveys the history and usage of this graph.

Ref.Wiki

So What’s a Heat Map and how it is useful for Web marketing?

Through years of research in web marketing, patterns have been seen in the ways that people not only navigate the web, but web sites and even web pages. All of this data was compiled by marketing firms and used to create a heat map.

Heat maps are charts that show us where most people look when they open a web site or page, by human instinct. The map displays regions colored yellow, orange and red – the darker the color, the more high-profile the spot is.

So if you are a web analyst/developer: simply look at a heat map before you design your next web site, plan to remodel your existing one, or are planning on remodeling your online advertising campaign, and make sure the ads are placed in the right “hot” areas!

Website Heat Maps

A heat map enables the website owner to determine what areas of a website the visitors find most interesting. It is best displayed visually.

Heat map image of Google

As you can see the more red the color, the greater the activity on that area of the website. Thus, for Google rankings the top 5 listings get a majority of the eye balls. You will also notice the red lines on the image, these represent the “fold,” the area above where you would have to scroll down to see more of the page.

Website Heat Maps with eye tracking

An eyetracking “heatmap” shows how much users looked at different parts of a Web page. Areas where users looked the most are colored red; the yellow areas indicate fewer fixations, followed by the least-viewed blue areas. Gray areas didn’t attract any fixations.