Dr. R.A.N.M ARTS AND SCIENCE COLLEGE�Affiliated to Bharathiar University , �Accredited with “ B+” NAAC
Mrs. S. Bibi Fathima M.Com., M.Phil.,� Assistant Professor,� Department of Commerce (CA)
Course Name : Software development with Visual basic
� Welcome You All
What is meant by client and server?
A network is set up between client system and server system to communicate with each other is called client/server network.
The computer requesting information is called a client. The computer responding to the request is called a server. The individual computers is called clients.
Client/server architecture:
A network architecture in which each computer or process on the network is either a client or a server. Servers are powerful computers or processes dedicated to managing disk drives (file servers), printers (print servers), or network traffic (network servers ). Clients are PCs or workstations on which users run applications. Clients rely on servers for resources, such as files, devices, and even processing power.
Technical Architecture :
Technology that separates computers and application software into two categories clients, and servers to better employ available computing resources and share data processing loads. A client computer provides the user interaction-facility (interface) and some or all application processing, while the a server computer might provide high-volume storage capacity, heavy data crunching, and/or high resolution graphics. Typically, several client computers are connected through a network (or networks) to a server which could be a large PC, minicomputer, or a mainframe computer. Every computer connected to a website acts as a client while the website's computer acts as a server. Also called client-server environment.
Application architecture:
Application architecture is one of several architecture domains that form the pillars of an enterprise architecture or solution architecture. Note that the term "application architecture" (without the s) is commonly used for the internal structure of an application, for its software modularisation.
Applications Architecture is the science and art of ensuring the suite of applications being used by an organization to create the composite application is scalable, reliable, available and manageable.
Two-Tier Architecture:
The two-tier architecture is like client server application. The direct communication takes place between client and server. There is no intermediate between client and server.
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The above figure shows the architecture of two-tier. Here the communication is one to one. Let us see the concept of two tier with real time application. For example now we have a need to save the employee details in database. The two tiers of two-tier architecture is
Database (Data tier)
Client Application (Client tier)
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So, in client application the client writes the program for saving the record in SQL Server and thereby saving the data in the database.
Three-tier architecture:
Multi-Tiered Architecture:
In 3-tier architecture, each server (tier 2 and 3) performs a specialised task (a service). A server can therefore use services from other servers in order to provide its own service. As a result, 3-tier architecture is potentially an n-tiered architecture
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Comparing both types of architecture:
2-tier architecture is therefore a client-server architecture where the server is versatile, i.e. it is capable of directly responding to all of the client's resource requests.
In 3-tier architecture however, the server-level applications are remote from one another, i.e. each server is specialised with a certain task (for example: web server/database server). 3-tier architecture provides:
A greater degree of flexibility
Increased security, as security can be defined for each service, and at each level Increased performance, as tasks are shared between servers