Image courtesy of GridTalk

So, we’ve all heard about clouds and grids. But what are the pluses and minuses of each approach? For that matter, just what exactly is a “cloud?” A just-published paper goes into this and more, with comparisons of grid computing and cloud computing.

Written by former iSGTW editor Cristy Burne (now of GridTalk) and available as a GridBriefing at the GridTalk website, the four-page document dissects the benefits and drawbacks of each approach, and draws upon opinions and sources as diverse as Hewlett Packard and the European Software Association. There is also a quick-reference chart that goes into such meat-and-potatoes issues as:

• Who provides the service?
• Who uses the service?
• Who pays for it?
• Where are the computing resources?
• Why use them?
• What are they useful for?
• How do they work?

Grids and clouds, side-by-side. Click image to read chart.  Image courtesy GridTalk.

Pointers

The GridBriefing has pointers to further essays and studies of grids and clouds, including a new, invaluable, much longer, e-Infrastructure ReflectionGroup (e-IRG) White Paper, written by Fotis Karagiannis of the Athens University of Economy and Business. The White Paper is in public consultation phase from now until 6 March, and the author is asking people to read it and send in comment to their archive, or to fkara at aueb.gr.

Seven topics were selected and examined in-depth in the document: Grid and cloud computing, Security, Education and training, Global
collaboration, Sustainability of the computing-related e-Infrastructure, Remote instrumentation, and Virtualization.

These hot topics were chosen after several rounds of consultation with experts belonging to the e-Infrastructure community, and were presented
to the e-IRG delegates at the e-IRG workshop in April 2008, in Zurich.

The initial reactions of cloud bloggers such as Markus Klems (“Cloudy Times: Random Thoughts of Markus Klems") are positive, saying: “Instead of describing theoretical features of grids and clouds, the authors take a look at two concrete implementations: the EGEE grid and the Amazon cloud (EC2+S3). This approach seems reasonable as it avoids long-lasting, fruitless discussions about how to define clouds and grids . . . Simplicity is an architectural design choice that I believe to be the major success factor of Amazon-style cloud computing. Easy-to-use interfaces allow third-party developers to hook into the cloud and build their own frameworks and tools on top of it.

Or, as the e-IRG authors put it: “In the medium term, the greatest potential benefit of cloud, as proposed by Amazon, is probably not the service itself, but its interfaces and usage patterns.”

For further information, see the e-IRG Facebook groups site and the press release.

—Dan Drollette, iSGTW