System Architecture

Last night I received a call from my sister (not God), whose going BBI from Jai Hind College, Mumbai. She kept on talking about her class, projects and how her life was moving ahead, until IT as a subject came into her life. I had just attended Dr. Mukerjee class on System Architecture, so being the elder brother I asked her not to worry about IT and decided to explain whatever I knew. The first session started with system architecture (as obvious).

Sister: System Architecture, is it something to do with structure.

I: Yes, you are on the right track, the structure that an orgainsation follows for its IT system. Companies have many computers, lots of application run on them, there’s lot of data that company has and uses. How does it manage to run all smoothly (if at all)? The answer to it is structure, i.e., system architecture.

Sister: Brother, in our computer also we do have lot of data, we also use some software, does it mean we also require system architecture.

I: Yes, what we use is single tier architecture, where the data and application are built within the system (CPU) itself. It is important to see whether the data and application are separated.

Sister: Do even companies use single tier architecture?

I: No, companies depending on their need use either of the following: 1. Two tier; 2. Three tier;
3. Multi tier.

Sister: Can you explain the criteria.

I: There are written criteria, companies where few applications are used, also where the cost of upgradation and maintaince is low may go for second tier architecture, for example our share broker. In three tier architecture the data server and the application server are separate from the user machine. In simple term any addition for software is done at a central place which then the users can just update following certain instruction. In a multi-tier architecture the addition is the use of internet. If you remember when you go ICICI bank they login to some system, that system is web based and is managed centrally from one location.

Sister: Hey it is making sense. Now it’s you responsibility to take me to all of your class as and when they happen.

I: Ok madam, as you say. Bye, it’s almost 45mins we have talked and it will cost me some Rs. 100 and that I will charge to you.

Sister: Why don’t you write on blog and send me the link I will read it from there. Bye, good night.