Hopefully, this post is not a book review. It's about Cloud Computing.

Microsoft's Ceo, Steve Ballmer said that the company plans to spend 9.5 billion dollars in 2010, to cloud computing. The company will launch, Microsoft Azure, a cloud computing system.

Google has recently announced its Cloud-Based Operating System, Chrome OS and according to Google, the future is in Browsers and in the Cloud.

Amazon offers Cloud Based Storage, and according to their web site : "Amazon S3 provides a simple web services interface that can be used to store and retrieve any amount of data, at any time, from anywhere on the web."

Quite impressive huh? Given all that, I decided to search over what is this Cloud Computing? What is Software as a Service? Why is this important?

The first helpful document that I came across on the web, was UC Berkeley's 25 page report about Cloud Computing which summarizes what is cloud computing, its obstacles and how can these obstacles could be exceeded.

In simple words, Cloud computing is a general term for anything that involves delivering hosted services over the Internet. As the report suggests 3 aspects are new in cloud computing:

1. Infinite computing resources available on demand: thereby eliminating the need for Cloud Computing users to plan far ahead for provisioning.

Simply you have resources, and demands of using these resources. That means you can meet demands under resource capacity, but you cannot satisfy them if demand exceeds capacity.

Let's say, you have a website, and users login to the website. You run couple of servers in order to process the login information from users. Assuming, your servers can only process 1000 user login requests that means if more than 1000 users want to connect to site, you turn many down. (You wouldn't want that). On the other side, when user login requests are less than 1000, and you run servers that can meet up to 1000 users, that means you are running some servers unnecessarily (You wouldn't want that either).

Or, let's say the demand of users wanting to use the site varies a lot. Some days there are 1500 user demands, whereas the next days you have less than 1000. So you decide to rent/buy extra servers, that means you take a risk, if extra servers are not used that means you spent money unnecessarily.

So here comes the cloud solution, instead of owning servers/data centers, you deal with a (yours*100000...) sized Data center, and pay them for the resources you are using. As these big data centers( Cloud Providers) are well sufficient to meet any change in demand, there comes Infinite computing resources available on demand.
That gives you elasticity and lets you transfer that risk.

2. The elimination of an up-front commitment by Cloud users, thereby allowing companies to start small and increase hardware resources only when there is an increase in their needs.

This aspect of Cloud Computing would motivate business ventures, as the initial costs of the startup would decrease.

3. The ability to pay for use of computing resources on a short-term basis as needed (e.g., processors by the hour and storage by the day) and release them as needed, thereby rewarding conservation by letting machines and storage go when they are no longer useful.

For a business, if running servers on its own is more costly than paying per resource used on the cloud provider, then Cloud Computing is very useful.

According to Berkeley report, there are 10 major obstacles,

1. Availability of service
2. Data lock-in
3. Data confidentiality and auditability
4. Data transfer bottlenecks
5. Performance unpredictability
6. Scalable storage
7. Bugs in large distributed systems
8. Scaling quickly
9. Reputation fate sharing
10. Software licensing

Berkeley researchers, list possible approaches in overcoming these obstacles. And they say that:

"we believe that over the long run providers will successfully navigate these challenges and set an example for others to follow, perhaps by successfully exploiting the opportunities that correspond to those obstacles."

Also Mike Clein, president of Online Tech, states that

"For many, online data storage is less expensive, faster, more secure, and more reliable than the tape backup systems used over the past several decades. "

So, the future of Cloud Computing seems very bright. Go Cloud!