The client server architecture

Abstract

In this assignment we talk about the client server architecture and its model and about its advantage and compare them with each other. Also provide some solution and comments about Hures Company.

Introduction:-

We are now in modern age of technology. Like old time we do not need to do our daily things with pen and paper now. Modern technology gives us the power to saves the time and work become more easy without any hassle .Now multinational companies using computer for their all task. So it’s become more essential for everybody for their daily needs and work. Everybody now depending on computer so it’s really important to build up relation between computers to computers and then we also need a server means powerful computer with high requirement .Server serve Client means the user .If server cannot control the client request then it’s become more complicated for every single users for that regain system can be crash .and technology update time by time so the system needs to be updated. If any company crate a system that can serve 100 employee but they have like 300 employee it’s not possible to cover everyone needs also its become pain for everyone to work with that system. So we need better system design means Better client server architecture. With the right level of attention to client/ server systems and application design. But poor design can ruin this utopian vision; making upgrades every bit as painful, time-consuming, and costly as installing a new mainframe.

Colin White writes that the “benefit of client/server computing is the availability of
Hardware servers that scale from a small uni-processor machine to a massively parallel
Machine containing hundreds, possibly thousands of processors. Corporations can now
match the computing power of the server to the job at hand. If a server runs out of
capacity, the old server can simply be replaced by a larger one. This change can be
made without affecting existing client workstation users or the tools they employ. This
provides not only scalability, but also flexibility in handling hardware growth as compared
with central mainframes where an upgrade is a major undertaking that is both costly and
time consuming.”
(Colin White, “Supporting High-Performance DSS Applications,” InfoDB 8(2) (1994), 27. )

Client-server architecture

A web page (HTML page) that contains the same information for all users. Although it may be periodically updated from time to time, it does not change with each user retrieval.

A program / script file executed on the web server in response to a user request. A CGI script is usually executed to process the data sent when a form filled in by a user is sent back to the web server.

Server side scripting means that all of the code is executed on the server before the data is passed to the user’s browser. In the case of PHP this means that no PHP code ever reaches the user, it is instead executed and only the information it outputs is sent to the web browser

PHP: Hypertext Preprocessor.PHP pages typically have .phtml,php or .php3 file name extensions. An open source technology.

ASP: Active Server Pages .A Microsoft technology. Extension .asp.

JSP: Java Server Pages .jsp pages contain Java code.

SSI: Server Side Includes. Involves the embedding of small code snippets inside the HTML page. An SSI page typically has .shtml as its file extension.

With this technology now it’s become really easy to create large website and maintain it easily.

Introduction to 2-Tier Architecture

Two-tier client/server architectures have 2 essential components

1. A Client PC and
2. A Database Server

Tier Considerations: Client program accesses database directly. Requires to code change to port to a different database. Potential bottleneck for data requests .High volume of traffic due to data shipping. Client program executes application logic. Limited by processing capability of client workstation (memory, CPU) .Requires application code to be distributed to each client workstation. (Less than 50 users).

Introduction to 3-Tier Architecture

3-Tier client-server architectures have 3 essential components:

1. A Client PC
2. An Application Server
3. A Database Server

3-Tier Architecture Considerations:

• Client program contains presentation logic only
• Less resources needed for client workstation
• No client modification if database location changes
• Less code to distribute to client workstations
• One server handles many client requests
• More resources available for server program
• Reduces data traffic on the network

Comparing both types of architecture

“Tier 2 architecture is therefore a client-server architecture where the server is versatile means it is capable of directly responding to all of the client’s resource requests. In tier 3 architecture however, the server-level applications are remote from one another, i.e. each server is specialized with a certain task eg:- web server/database server. Tier 3 architecture provides: “

• Flexibility.
• Increased security at each level.
• Increased performance.

Benefits of the Client/Server Model

1. Cost savings.
2. Scalability.
3. Manage workflow.
4. Provide multi-tier service
5. Instrumentality

Disadvantages of the client/server model

Client/Server architecture also has the following drawbacks:

• increased cost: due to the technical complexity of the server
• a weak link: the server is the only weak link in the client/server network, given that the entire network is built around it! Fortunately, the server is highly fault tolerant (primarily thanks to the RAID system) (http://en.kioskea.net/contents/cs/csintro.php3)

Problem Faced by Hures Company and its solution:-

According to the problems faced by Hures, its Primarily, it’s not that system they made for future use .it did not have that capability to the handle the future demands or needs of the company. the developer of the system did not focused on the future strength of the system or the adjustment of the system, different changes on both external and internal environment which change the over flow of information in the company. In order to come up with the current problem of Hures’ system, “Client-Queue-Client can be applied as alternative architecture. This uses a passive queue which allows the client instances to communicate directly with each other, which will refine their request from the services. This is helpful for Hures because it can help to support and prevent any problems that are related with the server” (Exforsys Inc n.d.).. “Client queue is used in order to take track of the number of client connections. Therefore, the server can trace which resources the client has obtained, and the server can release the resources after the client connection breaks down” (Chan & Leong 2003).

“Intranet is a network that is built by using the same tools and protocols that are used by the global Internet but applied instead to the internal network of an organization. It can be describe like a closed-circuit television system, which can be viewed only by those people within the organization that owns the system” (Lowe 2009).

“Intranet site is a web site that is viewable only to those within the network of an organization. Even though based on the same protocols as the World Wide Web, an intranet is protected from the outside world either by not being connected to the outside or through a series of hardware and software obstacles known as a firewall”l (Matthews & Matthews 2003, p. 64).

The development of an intranet web site using secure log cons to access the information is not a new idea. Many corporate locations use a secure internal site for vital information to be used by employees of the corporation and management only. The design of such a site could be simple using HTML, Java and CSS and may provide a variety of links to various databases stored within the network server(s). Security features can be enhanced by requiring the changing of passwords on individual users every thirty (30) days. Obviously, one counter position of establishing an internal web site would be that of cost and implementation. Depending upon the OS of the server, it would be necessary to create the web site and establish users with passwords to access the site. This would take some time to develop and the amount of individuals accessing the site would have to be considered in the overall budget required for implementation.

Threats to the security of any open network system will always exist. Proper network monitoring on a continuous level severely reduces the risk of infiltration from outside sources. Network security should be the most important aspect of any company/corporation within the network structure. Reducing allowable events such as user abilities to plug in devices to their individual workstations, remote monitoring using camera feeds in various places within the office. Again, the cost of this will be substantial however, to maintain the integrity of the network should be of the highest priority and can reduce the severity of lost revenue. Disadvantages in intranet that it’s really expensive to maintain and setup. Need high qualified people or team to maintain its resources. Peer-to-peer and client-server architecture have different advantages and pros. It enables to take advantage of the wireless and Internet technology, at the same time, take advantage of the privacy and security which can be offered by client/server system. Intranet and internet both are famous worldwide so i will develop daily basis and needs to upgrade time wise.

References:

Books:-

• Colin White, “Supporting High-Performance DSS Applications,” InfoDB 8(2) (1994), 27.
• Chan, A T S & Leong, H V 2003, Cooperative Internet Computing, S:pringer.
• Lowe, D 2009, Networking for Dummies, For Dummies.
• Matthews, M, Matthews, C B & Poulsen, E 2003, Microsoft Office FrontPage 2003: The Complete Reference, McGraw-Hill Professional.

Website:-

• http://members.tripod.com/ChannuKambalyal/NTierArchitecture.pdf
• http://www.webdevelopersnotes.com/basics/client_server_architecture.php3
• Exforsy:-Peer-to-Peer and Client-Queue-Client Architecture, http://www.exforsys.com/tutorials/client-server/peer-to-peer-and-client-queue-client-architecture.html [Accessed 17 February 2010]