In this chapter we are going to deal with the major points behind choosing a simple chat system as a baby thesis and why visual basic 6.0 is the programming language we choose, with a general overview about the project and how it works. So turn this page quickly and get yourself ready to find how it is working.
1.1. Why Student Information System ?
We we’re thinking that the school need an electronic Student Information System
1.2. Why Visual Basic ?
Two main reasons why we choose Visual Basic as the programming language for this project. The first is that Visual Basic 6 is one of the Microsoft’s greatest language for Visual programming. Although writing programs can be a tedious chore at times, Visual Basic reduces the effort required on your part and makes programming enjoyable. Visual Basic makes many aspects of programming as simple as dragging graphic objects onto the screen with your mouse. The second reason which is the main one is that we are going to use a control called windows socket or WinSock as you will see in the following chapters, and this control is some how has a low level interface. The only high level languages that deal with windows sockets is Visual Basic and Visual C++, and since Visual Basic is more easy to learn in small period of time than Visual C++, it was chosen to be the programming language.
1.3. General Overview
As a matter of fact there are several varieties of chatting. The simplest computer chatting is a method of sending, receiving, and storing typed messages with a network of users. This network could be WAN (Wide Area Network) or LAN(Local Area Network). Our chatting system will deal only with LAN’s (static IP address) and it is made up of two applications one runs on the server side (any computer on the network you choose it to be the server) while the other is delivered and executed on the client PC. Every time the client wants to chat he runs the client application, enter his user name, host name where the server application is running, and hits the connect button and start chatting. The system is many-to-many arrangement; every–one is able to “talk” to anyone else. Messages may be broadcasted to all receivers (recipients are automatically notified of incoming messages) or sent to special individuals (private chatting through server) where during this operation all messages are encrypted at the sender side and decrypted at the recipient to disallow any hackers to the server from reading these private messages. For this system to be physically realized you should be familiar with programming and networking. Visual Basic is our programming language, TCP/IP is our network protocol, and finally “windows sockets” is our programming interface to have access to network functionality. This is a first glance at our senior project and the rest of explanations and ideas are eagerly waiting for you in the next chapters.
In this chapter, we are going to give some light on the main concepts and ideas we use to build our project. What we mean by network application, protocols, ports, and how do they interact with each other. Windows sockets, how it works and how we are going to use it in our application. All these information will be available for you in this chapter.
2.1. Network Application
Network application exchange data between physically separated machines. For this to occur the machines must be connected by a transmission media. There are many different types of communication links and new ones continue to be developed. Coaxial cables, phone lines, digital phone lines, fiber optic cable, satellite beam, and infrared waves are all used as transmission media for exchange data between computers. A network includes a group of computers connected by a physical link allowing data to be exchanged between them. A local are network on LAN is a network of computers in close physical proximity, usually a single building,...