After my earlier blog discussing the evolution of IT, I had several discussions on the benefits and challenges of virtualization, private, and public clouds.  Following bar chart is an attempt to capture the benefits and challenges of various phases of IT evolution from the days of having dedicated physical servers for each application to the use of public cloud.

The chart is self explanatory, some key points to note are:

• Going from virtualization to private cloud is basically a step to provide self service capabilities to the application owners.  It increases flexibility and also increases the management complexity, as it adds another layer of abstraction
• The biggest advantage of using public cloud is reduction in fixed costs, as you don’t have to build the capacity for exceptional peak cases.  Several IT activities have elastic demand, development, functional testing, load testing, end of quarter processing etc.

Read the original blog entry...