Abhi14185’s Weblog

This is a conversation between me and Riki my friend. He came to my house when I went there for two days. He has given CAT and is interested to join PRAXIS this year.

Riki-                How your studies are going? Do you have I.T. in your

                        3^rd Semester also?

Me-                 No, we have Systems Engineering instead.

Riki-                What are you studying in System Engineering?

Me-                 The first class was on Computer Architecture.

Riki-                Computer Architecture? What is that?

Me-                 Computer Architecture is the design of a computer system. It sets the standard for all devices that connect to it and all the software that runs on it. It is based on the type of programs that will run (business, scientific) and the number of programs that run concurrently. In short, it is the science and art of selecting and interconnecting hardware components to create computers that meet functional, performance and cost goals.Is it clear?

Riki-                Yes! But can you give me some more details?

Me-                 Ok. There can be single tier architecture, two-tier architecture, three-tier architecture or multi-tier architecture.

Riki-                So can you kindly explain how these are different from each other?

Me-                 Ok, let me start with single-tier architecture.

Riki-                Fine!

Me-                 Single-tier architecture is an architecture in which data and the application are separated even if they reside in the same physical hardware. Example: The MP3 songs and the VLC Music player, both are stored on my laptop.

Riki-                Ok. Now the two-tier architecture?

Me-                 Yes, in this case the data base is situated in the main server & various applications are located in the individual machines. This data base is connected to applications located in individual machines through internet or L.A.N or through W.A.N. Example: Usage of database by the students of a MBA institute. But this needs high bandwidth.

Riki-                Fine! Now can you explain the other tiers?

Me-                 Definitely! The next type is three-tier architecture which is exactly the same as two-tier architecture excepting the fact that in three-tier architecture the application is separated in two parts. One part contains all the business critical applications & another part contains the general applications. Here the data transfer over network is minimised.

Riki-                Is there is any other tier left?

Me-                 Yes, I told you that there are four types. Multi-tier architecture is still left.

Riki-                Oh! I just forgot. Tell me.

Me-                 In this architecture, internet is used in place of W.A.N or L.A.N.  The client servers are attached to the database & the application servers which are stored in different servers. It does not need any specialist software at the client location.

Riki-                So, you must be having a good teacher! Right?

Me-                 Yes! He is our new teacher and his tag line is “Living ON Web 2.0 / Living OFF Web 2.0″. So from this you can understand how passionate he is about I.T. He has created “Kollaborative Klassroom” at yantrajaal.com we post our assignments there on “wiki”. So, have you got a brief idea?

Riki-                Definitely! See you!

Me-                 Bye!