Client Server Architecture for DOT NET

CLIENT SERVER ARCHITECTUREA client/server system operates as outlined in the following diagram:

The client sends a request to the server using its IP address and the port, which is reserved for a particular service running on the server.

The server receives the request and responds using the client IP address and port

2 -TIER ARCHITECTGURE

2-tier architecture is used to describe client/server systems where the client requests resources and the server responds directly to the request, using its own resources. This means that the server does not call on another application in order to provide part of the service.

3-TIER ARCHITECTURE

In 3-tier architecture, there is an intermediary level, meaning the architecture is generally split up between:

1. A client, i.e. the computer, which requests the resources, equipped with a user interface (usually a web browser) for presentation purposes

2. The application server (also called middleware), whose task it is to provide the requested resources, but by calling on another server

3. The data server, which provides the application server with the data it requires

MULTI-TIER ARCHITECTUREIn 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

ADVANTAGESThe client/server model is particularly recommended for networks requiring a high degree

of reliability, the main advantages being: 1. centralised resources: given that the server is the centre of the network, it can manage

resources that are common to all users, for example: a central database would be used to avoid problems caused by redundant and inconsistent data

2. improved security: as the number of entry points giving access to data is not so important

3. server level administration: as clients do not play a major role in this model, they require less administration

4. scalable network: thanks to this architecture it is possible to remove or add clients without affecting the operation of the network and without the need for major modification

DNADistributed iNternet Architecture

Win32 Web Device

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ADO

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