System Architecture

Paras :- Hi Jay, How was the first class of System Engineering ?

Me:- It was good. Sir gave introduction and start teaching from the system Architecture. You can see those slides in kk.yantrajaal.

Paras: - Ya I saw those slides but I couldn’t download it and it seems hard to read as the font is small. Can u help me out to give brief idea about what system architecture is all about?

Me :- yes definitely. See these slides tell about the different types of Tiers used in the system architecture. Basically the important principle of system architecture is that the data application should be distinct means while preparing the application the program should read the values or commands from the distinct point.

Paras : - and what you were talking about tiers in system architecture?  

Me:- There are 3 tiers in systems architecture.

They are differentiated as single tier, Two Tier, Three Tier and Multi tier.

In two tire architecture, the data is kept in server and the applications are in the individual computers. To connect these data center and individual computers LAN network is used.

Paras: - What are the advantages of the Two Tier system architecture?

Me:- Advantages of this are: as data and applications are stored in different places it does not put burden on server machine when the number of users are more.

But the problem in this is if more number of users is there then the bandwidth can become a problem. Or else the application will become slow.

Paras: – which are the other tiers of the system architecture?

Me:- Other tiers are three tier and multi-tier. Let me explain it to you.

In three tier the application and data is kept centrally in different servers. The users computers have only user interface. This tier helps when all the business applications and data need to be kept in centralized place and any change in the business process must affect whole business.

Example might be if company changes its credit policy from 20 days to 15 days then with the help of this kind of architecture the change will be done to all the centers at a time.

Paras: - and multi tier architecture?

Me:- In multi tier architecture system internet and web applications plays main role. In this multi tier architecture data server, business applications and server for web browser are there in main office and other places or computer are connected to it through Internet. Internet plays a role like WAN connection as in the two tier and multi tier architecture. Sometime the business application and web server are single only but it depends on the company`s policy and usage.

Paras: - this is about the data structure but how company uses the data from the database? Do they use any special program?

Me :- How company uses the data from Data Server? With the help of which

To use the data from the database some companies prepare their own programs for each of its function like HR, Finance, Sales, and Mktg etc.  Or some companies buys ERP systems of SAP, and Oracle etc.

Paras :- But what is preferable ? buying or making these programs?

Me: – It depends on companies policy. Cost and time are main constraint in this decision.

Paras: –  But what are the advantages or plus points of ERP systems?

Me: –  Advantages of Using ERP programs are:

It provides integration of data over all centers it means synchronization of data is done automatically.

To serve all the areas of oraganisations, company can buy ERP from single vendor. The advantage is these vendors prepare these ERPs taking into consideration the best practices               available which assure us to the quality of the product.

As these are readymade systems, ERP are also faster implement and they are easy to maintain.

Paras: – But what if there are any special department which needs to use its own application than ERP?

Me:- In case of any special work or job which need special software they can have it. Again they can link with ERP and have some special software’s or they can use different program to replace ERP.

Paras: - But in multi tier when the applications are web based it have the danger of data theft, right?
Me:- yes. When Database, web server and ERP system are loaded on main server and they are linked to the other places with the help of Internet then there is always a danger of data theft or hacking. This danger can be served with the help of firewall. Firewall can save the systems from data theft and virus also.

Paras : – Thank you Jay to help me .But I must say this is interesting subject.

Me : – You are welcome yaar and while telling you I also revised my knowledge. Bye.