(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.
