System Architecture explained in simple terms

(After a long hectic day in class, I came to hostel to have some rest. One of my close friend called me and enquired about the happenings in VGSOM)

Karthik: Hey man, watz up?

Me: Hey karthik, It’s a long day man. It’s very hard to sit in class after working in an IT company.

Karthik: oh, is it that boring?

Me: Not like that. Today, we had a very good session on Systems architecture and I felt guilty that I couldn’t know basic things even though I worked in IT industry.

Karthik:  oh, that’s interesting. Can you explain me a bit on that?

Me: Yeah sure. Basically system architecture deals with the way of designing the components to perform its work.

Karthick: I couldn’t get you. Can you explain it in a simpler way?

Me: System architecture basically determines the structure of the system and its components.

Karthick: That means system architecture is customized based on our needs.

Me: yeah, we have single, two or multi tier architecture based on its function and our needs.

Karthick: Can you explain to me in detail.

Me: Yeah. Lets me explain about single tier architecture. Single tier architecture is that all the user interface of a web application, the middle ware and the data contained in a single unit.

 

 

Karthick: Oh, this means it is cost effective and simpler.

Me: Yeah. It will be of very useful in small business environment e.g. grocery shop. The drawback of this system is only one user can use it.

Karthick:  So what is two tier architecture, does it overcome the shortcoming of single tier architecture?

Me: Two tier is an enhanced version of single tier architecture where database and application are stored in two different machines.

Karthick: Oh.

Me: Here we will have a common database and the customized application were installed in different machines .All the application data computer will access the common database via LAN or WAN e.g. in a supermarket where all the sections of the store connected to the same database which stores the transactions. 

 

Karthick: So it is a multiuser rather than single user, the drawback of single tier architecture.

Me: Yeah, but this structure will have fair share of drawbacks. Since it is accessing the common data machine, the speed will get decreased if large number of data connected to it. Suppose if we want to change the business logic, I need to update all the computers connected to it individually. It is costly and time consuming.

Karthick: Does three tier overcome these drawbacks?

Me: Yeah literally. In three tier system, we will have middle tier which houses all the business logic. It basically acts as channels between user interference and databases. Suppose if we need to change the business logic, it is sufficient to change the logic only in the middle tie which houses it. The changes will be reflected in all the systems connected to it.

Karthick: can you show the pictorial representation of the structure?

Me: Here you go…

Karthick: Thanks man for explaining about system architecture.

Me: Hold on, we have multi tier system architecture.

Karthick: What was that?

Me: Multi tier system architecture is mostly web based where in web server is connected to three tier architecture and all the application machines will connect web server via internet. 

Karthick: Is there any security threat as we are connecting the server via internet?

Me: Security threat can be overcome by robust firewall settings. Also, main advantage of this structure is it is less expensive.

Karthick: That’s too informative. Thanks for sharing the information about system architecture.

Me: Yeah you are always welcome.