System Architecture

Information Systems Engineering

Systems Architecture

This is the conversation on information system architecture between me (Abu Talib) and my friend Faizaan Alam. He is a computer engineer form IIT Delhi. I went to his home to meet him. He asked me about my study and the paper of this term. I told him about my study and subject. Then he said I am going check your knowledge on information system architecture. And the conversation was as fallow.

Abu Talib = A

Faizaan Alam = F

F – What is an Information systems engineer?

A – The information systems engineer may be called upon to design and develop databases, develop system architecture, establish system standards, integrate an information system with varied data sources and networks, and generally to plan, integrate, design, test or operate information systems. In short its combination of database and application.

Database: describes WHAT is to be processed

Applications: specifies HOW it is to be processed

F- Can you define Information, System, information system, and engineering separately ?

A - Information: - is anything that you are capable of perceiving. This can include written communications, spoken communications, photographs, art, and music, nearly anything that is perceivable.

System: – is a group of interdependent items that interact regularly to perform a task. System often simply refers to the operating system (OS). OS concerned with the development and structure of complex programs which facilitate man-machine communications.

Information system: - is a system that collects and stores data

Engineering: - is the endeavour that creates, maintains, develops, and applies technology for societies’ needs and desires.

F- Good now tell me, what is System Architecture?

A – Arranging the data and processes for the best utility is the result of deploying architecture. The architecture must define the rules, guidelines, or constraints for creating conformant implementations of the system.

F- Can you define architecture?

A – It is nothing but the study and use of mathematical logic to design electronic circuits.

F- What is computer science?

A - In its most general form it is concerned with the understanding of information transfer and transformation. The discipline ranges from theoretical studies of algorithms to practical problems of implementation in terms of computational hardware and software.

F- How many type of application architecture, it advantage and disadvantage?

A – There are four types of application architecture?

Single Tier: Integrated Systems

Data and applications both are separated even if they are on the same physical hardware

Example: – Laptop / desktop / server

Two Tier: Client Server Architecture:-The term “two-tier” describes the way in which application processing can be divided in a client/server application. A two-tier application ideally provides multiple workstations with a uniform presentation layer that communicates with a centralized data storage layer. The presentation layer is generally the client, and the data storage layer is the server.

Oracle / mySQL / SQL Server / DB2 are server software

Business Logic, presentation Logic are application software stored in individual machine.

Local Area Network:-Connects clients machines to server using TCP / IP protocols

Its advantages: – It has convenient graphics user interface. Does not place processing burden on server machine when you have hundreds of users

Its disadvantages: – High Bandwidth requirements, slows down application, Wide Area Network (WAN) issues Maintenance / Version Control of distributed software.

Three Tier Architecture: - three-tier architecture adds to the two-tier model a new layer that isolates data processing in a central location and maximizes object reuse.Its application is partitioned, business logic kept centrally if there is need for changes to business logic it done at one location ,and presentation logic kept locally that minimizes data transfer over network.

Its advantages: - Any change in the database ends up costing you a change in the presentation layer. To avoid this extra cost, you should isolate your database connection so that your presentation does not care anything about the way you store your data.

Its disadvantages: - is the level of complexity it adds to a system. You have more distinct components in your system, and therefore more to manage. It is also harder to find software engineers who are competent in three-tier programming skills such as transaction management and security.

Multi-Tier Architecture: – a specific kind of three-tier architecture. Variations on it are certain to work, but its essential characteristic is that it is distributed three-tier application architecture. Distributed three-tier architectures enable the three logical tiers of three-tier architecture to be distributed across many different process spaces.

Advantages: - No need for specialist software at each client location

Disadvantages: - Business Application has to be “web enabled”

F – Now, can you tell me the difference between internet and WAN.

A – Internet is no different from WAN both are TCP / IP but WAN is private, Internet is public network. Internet is Inexpensive there is no need to invest in corporate (private) network. But it is Insecure there is need to use security software for corporate use.

F – Explain multiple application.

A – Multiple applications:-it have specific requirements and distinct data, it distributed across more than one machine. These applications could be from different vendors or developed in-house based on different technology platforms Oracle? Excel? Java? C++?

F – good, Can u tell me the advantages of an Integrated Database System (RDBMS)?

A – There is no duplication of data, no inconsistency of data across locations / time periods, easier to manage, backup and restore facility, security and user access authentication.

F – Last question, tell me the advantages of an Integrated ERP System?

A – It gives tighter integration across all functional areas, there is no separate activity required to synchronise data, it can be purchase as a single package from established vendors, its benefit from best practices available with other companies, it is faster to implement, easier to manage and maintain.