Client server architecture

Abstract

This report is about the client server network architecture in which each computer or process on the network is either a client which is low end computer which request services and or a server which is high end powerful computer which is highly capable of providing services to many different clients at the same time. The task which servers performs are like managing disk drives which are called file servers, managing printers which are called print servers or managing network data traffic known as network server. Clients are PCs which require or use these facilities from servers which include sharing files, printers, storage and sometimes processing. All the clients and servers in a network communicate by using different protocols which are set of rules or standards which govern the communication between any computers or devices connected in a network. This client server architecture is also known as two-tier architecture.(1)

Introduction

The advent of personal computers gave birth to the idea of client/server architecture. Before personal computers, programs were written for mainframes. Software written for mainframes was often coded in a monolithic format that is the user interface, business logic and data access functionality are all contained in a single application. Because the entire application ran within the mainframe this was not a problem.(2)

Client/server model, needed to share many kind of services. As time passed the need of these services increased so servers also evolved. Many clients started sharing services of common server. Example can be of our web browser which is a client and requests services from web server like web pages or files. This is sometime also knows as Hyper Text Transfer Protocol server (HTTP) also for computer to make requests like a client Transfer Control Protocol/Internet Protocol (TCP/IP) and for transfer of files over internet File Transfer Protocol (FTP).Protocols are set of rules or standard that which governs the communication of two or more nodes in a network.(3)

The relationship between two computer programs in which one program makes a request and other which provide the required service is called a client/server relationship. It is a backbone of interconnection of two or more programs or computers anywhere across the network. Example could be an ATM machine in which we send request for balance check or money withdrawal and through this machine which is like a client and bank has supercomputers which acts as servers and the transaction are handled by them and result is sent back to the client to display in front of user.(4)

Client Server Architecture has two common architectural models. The two tier and the three tier architecture. In two tier architecture the application will be on the server instead of client because server has more disk space and power as compare to PC also the data will also be in server along with the application. In three-tier architecture the load is divided between two different servers instead of putting load on one and jamming other clients. These servers are database server and application server. The data and application are divided between these servers. Client would only request and display data. In this tier more manageable and less contention system for resources will be available because each server will be used either to process data or application requests.(6)

Literature Review

In modern world because of rapid changes in user requirements and increasing amount on daily basis of users sharing data among them the needs of faster and better network system growing tremendously companies are bound to upgrade their system every six months. Now Hures is also facing same problems. This is very common problem in any company because of the rapid development of business systems so to cater these problems any company should keep this in mind while developing new system is that they may need to upgrade very soon. Hures analyst did not plan the future scenarios properly and because that even internal and external environment is affecting the company.

1. The business is affected by many changes like political, social and technological. Client/Server technology is often introduced for flexibility of coping with these changes. However it comes with its own challenges which we will discuss here.
1. Client/Server is built on three basic building block they are client which is a small or less capable hardware or software then middleware which is a software which lies in between and server more powerful then client.
2. The first block client runs different applications on its operating system which provides graphic user interface. Clients could have web browser for example as an application requesting services now operating system transfers these request to the middleware. Client also runs a DSM (Distributed System Management) it could be simple element to the entire front-end managing application.
3. Middleware is application which has three categories: transport stack, network operating system (NOS) and server-specific middleware. It runs on both the client and the server. It also have DSM like clients and is the backbone of client/server architecture.
4. Server is typically intelligent software or hardware it runs some application to make an interface with middleware. Server consists of five main components SQL database, TP Monitors, groupware , object and the web. Server also has DSM in it which can be a simple agent or entire back-end of the system. The Distributed System Management application runs on every node in the Client/Server network.

2. The additional server like email could be used depending on size and usage of the network. Hures could also use similar OS in all workstations it also plays very important part in Client/Server. Same OS on all sides in network can reduce a lot of problems and it will increase server efficiency and will cause less strain on servers.
1. The Alternative architecture which could overcome Hures problem can be client queue client or another one called peer to peer architecture. Client queue client Architecture is also called passive queue Architecture.
2. In Client queue client all points including servers are simple clients. It was developed to continue on traditional Client Server Architecture. In this they were trying to make one client as a server for different clients to multiply the usage for clients. Hures could benefit from this track and order number of clients for better efficiency also there will be better resources distribution and sharing. Example is search engine which uses spidering for faster and better results.
3. Peer-to-Peer Architecture rather than focusing on power of server it distinguishes itself by distributing power and function. It depends totally on bandwidth and power of different nodes in the network. This architecture goes against previous client server architecture where there is one central server it replaces it with nodes which function as clients and servers simultaneously. Hures could use this architecture because due to its encapsulation it makes it easier to repair or upgrade without clients being affected and it’s more secure and easy to maintain.

3. Intranet is one of the oldest and safest way for any company to have communication among themselves. It works just like website on internet. It gives you options to log ons to access only authorize data at your level in company. Most of the corporations use intranet for sharing important data among the employees. Intranet is a kind of network which is built by using same tools and protocols used by internet or World Wide Web (WWW) but is only restricted to the network of this company only. It uses same HTML, Java and CSS and also provide same database to store data within network server. Security features are fully customizable so it’s your preference whether you want to change password every 30 day or to set different accessibility for employee depending their post and work in the company. Any outside person trying to access company files will be blocked by firewalls.
1. The Advantages of this internal network is that inside employees can do very important information interchange very quick and secure. It makes the data sharing more effective, easier and effective manner. It can also be used for internal applications such as newsletters, policy manuals, and price list etc. It can also gather information related to expense and programs that can help to transact application. As it is a private place on internet it’s safer and secured because only authority can access the website.
2. The Disadvantages of this intranet to be considered would be like firstly it is very expensive to setup and maintain because a special team of people need to be hired and trained for handling the process of managing resources of this particular company and organizing them in the website. This process will also be very time consuming to develop and also the number of individual users would have to be considered in the overall budget for planning, designing, implementing. Also to maintain the quality, testing and maintenance needs to be done at all time. Obviously once whole site is developed now each user in company needs to be trained also how to use and set up your passwords which will also affect overall budget.

4. It is very true that the popularity of intranet software and the internet pose threats towards traditional client/server system because intranet software have more advantages as compared to peer to peer or client/server architectures. It takes the most advantage of networking technology in the business world and because it enables us to take full use of wireless and internet technology at the same time it is the most flexible most secure and gives more privacy as compared to offered by traditional client/server system. As a result it is the most popular choice among many companies. However it is also very important to keep in consideration that even though intranet is the most popular and successfully used and accepted worldwide, there are still parts in the system or particular company which needs to use traditional client server system. As far as security is considered there are always threats to any open network system. To reduce the risk of infiltration from outside sources proper monitoring of network on continues level is severely needed. The most important aspect of any company/corporation should be the network security. Cctv could be installed in various places to remotely monitor all the activities of users within the office and no one should be allowed to use their plug n play devices to any individual workstation. Maintaining the network integrity should be of the highest priority and could reduce the unplanned damages to revenue but again the cost of doing all these procedures will be substantial.