What is Cloud Computing ?
Well, I have received the question “What is SQL Azure?” many times in an email and in IT events I go. I generally write blog about SQL Server but I have not written anything about SQL Azure so far. Before I actually answer What the SQL Azure is, I have to explain a small bit about “Cloud” first.
Basically to setup IT infrastructure, any company would need:
- Computers with Operating system (Server and/or desktop)
- Software to install on top of Operating system, to cater the need of users, such as Exchange Server, MS Office, Share Point, SQL Server, IIS etc.
- Highly scalable Network/Internet
Provided list of software is just to give an understanding to the readers otherwise this list can easily grows up long & long.
To setup this IT environment, company has to pay a lot for hardware and software licensing. Even after establishing IT infrastructure or website, whenever company grows, it needs to keep changing the infrastructure based on the growing needs of business and again company has to pay up-front for all these requirement whereas, in cloud you don’t need to worry about, you can increase or decrease capacity of whatever infrastructure / software you are using and have to pay for only what you are really using. Apart from this, you don’t need to employ staff to maintain this infrastructure even you will get 99.9% up time monthly SLA from almost all the major cloud service provider.
Now, question comes to your mind that how they provide Operating system along with software we need? This is really very valid question and the answer will laid down in the following paragraph.
Cloud computing comes in several different categories and you have to choose what exactly suits your need, some of the popular categories of cloud are defined here:
- Platform as a Service (PaaS)
- Infrastructure as a Service (IaaS)
- Software as a Service (SaaS)
These are three very popular services, out of few more, that cloud service provider provides.
Platform as a Service (PaaS): As name suggest, this service provides you a platform where you can host your application without worrying about Hardware, Operating System, Performance of Operating system, update SPs and other patches to Operating system. Microsoft provides “Microsoft Windows Azure” as a PaaS.
Infrastructure as a Service(IaaS): Iaas basically cater your needs related to networking, load balancing, security, firewalls and much more as long as Infrastructure concerns.
Software as a Sercvice (SaaS): As name describes, this model provides a complete leverage of cloud where you can get SaaS software enabled in your cloud space along with utilization of IaaS and PaaS. You may have CRM, E-Commerce application, Exchange Server, Lync Server, Share Point, Office Professional and many more. In SaaS model, you can even get support of programming framework like .NET, JAVA, PHP to cater the need of your own customized application. You can also ensure that you get relational database support, if needed, in form of SQL Azure.
Hope this makes your concept clear about Cloud Computing.
Images used in this article were taken from “Wikipedia”
Reference: Ritesh Shah
Note: Microsoft Books online is a default reference of all articles but examples and explanations