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INFORMATION SYSTEM TECHNOLGYFALCULTI PENGURUSAN DAN PEMBANGUNAN SUMBER MANUSIAASSIGNMENT 2Network StrategyName: Nichal Thien Mei LingMatric No.:A11HA0080Network Strategy Every network has strategy, or way of coordinating the sharing of information and resources. The most common strategies are terminal server network, client server network, peer to peer network, and distributed processing network. Terminal Server NetworkGenerally in information technology, a Terminal Server is a hardware device or?server?that provides?terminals which are PCs, printers, and other devices with a common connection point to a local or wide area network. The terminals connect to the terminal server from their?RS-232Cor RS-423?serial?port. The other side of the Terminal Server connects through network interface cards (NIC) to a local area network (LAN) is usually an?Ethernet?or?token ring?LAN through?modems to the dial-in or out wide area network, or to an X.25 network or a 3270 gateway. Different makes of terminal server offer different kinds of interconnection. Some can be ordered in different configurations based on customer need. The use of a Terminal Server means that each terminal doesn't need its own network interface card or modem. The connection resources inside the terminal server are usually shared dynamically by all attached terminals.In a terminal server network, processing server is centralized in one large computer, with the capacity to handle a large number of connections. The nodes connected to this host computer are either terminals with little or no processing capabilities or microcomputers running special terminal emulation software such as Windows Remote Desktop. (See Figure 1)3547110159067500-80645159067500Some Terminal Servers can be shared by up to 128 terminals. The terminals can be PCs, terminals that emulate 3270s, printers, or other devices with the RS-232/423 interface. Terminals can use?TCP/IP?for a?Telnet?connection to a host, LAT to a?Digital Equipment Corporation?host, or TN3270 for a Telnet connection to an IBM host with 3270 applications. With some terminal servers, a given terminal user can have multiple host connections to different kinds of host operating systems (UNIX, IBM, DEC). Many airline reservation systems are terminal networks. A large central computer maintains all the airline schedule, rates, seat availability, and so on. Travel agents use terminals to connect to the central computer and to schedule reservations. Figure 1One of the Terminal Server Network advantages is the centralized location and control of technical personnel, software and data. Besides that, it also reduced initial implementation costs. Since the processing work is done by the Terminal Server, client terminals are very cheap as they are completely diskless and run the minimum of hardware. While a Terminal Server is more expensive than a standard desktop system this cost is offset by the reduced cost of client terminals. Furthermore, it can reduced running costs where client terminals require very little on-going maintenance and attention. Since only the Terminal Server itself needs to be maintained running costs are kept to a absolute minimum. Terminal server network is upgradability. Because when it comes time to upgrade to a newer operating system only the Terminal Server needs updating. The client terminals need not be touched at all. In addition, this strategy is flexibility which user will not need to sit on any particular client terminal to access their user account. Any user can sit at any terminal client and by providing a valid username and password they are able to access their account.However Terminal Server network has its disadvantages also. One of the disadvantages is the lack of control and its do not use the full processing power available with microcomputers. Other than that, the display speed is slow. Sometimes when the server and/or network is under heavy load the display on the client terminals may be a little slow. However a well setup server and connecting network will alleviate this problem in most instances. A high quality animated graphics may also be slow to display. Generally the network connection between the client terminal and the Terminal Server is fast enough to handle a movie clip however performance may suffer if a number of users are doing this at the same time. A 3D animated graphics display (normally used for 3D games) is not possible on a client terminal. Besides, the client terminals rely on the Terminal Server to function. If the Terminal Server is unavailable for any reason the client terminals will cease to function. Furthermore, terminal server network has no floppy or CD-ROM.Client-Server NetworkClient-Server networking is a paradigm which is most commonly used in networking the world 388683537973000over. As the name makes pretty clear, the definition of a client server network is that one of the involved parties acts as a client and the other acts as a server. Client-Server Network use central computers to coordinate and supply services to other nodes and network. The server provides access to resources such as Web pages, databases, application software, and hardware (See Figure 2). This strategy is based on specialization. Server nodes coordinate and supply specialized services, and client nodes request the services. Commonly used server operating system are Windows Server, Mac OS X Server, Linux and Solaris. For example, at this very instant your computer is acting as a client requesting this webpage from the Make Use Of server, which is then happily responding back with the page you requested. The client then receives the page and shows it to you, enabling you to read this wonderful article!That is the gist of it. If you ever had to explain yourself or someone else what client server networking or client server computing is, explaining it with the above example will suffice. If however you are interested in diving a little bit deeper into the definition of a client server network, you are most welcome to follow along.Client-Server Networks are widely used on the Internet. For example, each time you open a Web browser, your computer (the client) sends outs a request for a specific Web page. This request is routed over the Internet and server. This server locates and sends the requested material back to your computer.3540125171450-152401714500Figure 2The advantage of the Client Server Network strategy is the ability to handle very large networks efficiently. Another advantage is the availability of powerful network management software to monitor and control network activities. Besides, Client Server Network has no central administration, here in this architecture there is a centralized control. Servers help in administering the whole set-up. Access rights and resource allocation is done by Servers. Furthermore, it stored all the files are at the same place. In this way, management of files becomes easy and also it becomes easier to find files.? It is easy to make a back-up of it as all the data is stored on server. Therefore, if in case of some break-down if data is lost, it can be recovered easily and efficiently. There is an up gradation and Scalability in Client-server set-up. This changed can be made easily by just upgrading the server. Also new resources and systems can be added by making necessary changes in server.?From various platforms in the network, server can be accessed remotely. In addition, servers can play different roles for different clients.The major disadvantages of Client Server Network are the costs of installation and maintenance. It is very expensive to install and manage this type of computing. You?need professional IT people?to maintain the servers and other technical details of network. Besides that, there is too many requests from the clients may lead to congestion. Overload can lead to breaking-down of servers. If you are downloading a file from server and it gets abandoned due to some error, download stops altogether. It can the summarized that client-server model is not used in small scale networks and networks where security is not a big issue.?Peer-to-peer (P2P) NetworkIn a P2P network, the "peers" are computer systems which are connected to each other via the Internet. Files can be shared directly between systems on the network without the need of a central server. In other words, each computer on a P2P network becomes a file?server?as well as a client. Peer-to-peer (P2P) Network, nodes have equal authority and can act as both clients and servers (See Figure 3). The only requirements for a computer to join a peer-to-peer network are an Internet connection and P2P software. Common P2P software programs include Kazaa, Limewire, BearShare, Morpheus, and Acquisition. These programs connect to a P2P network, such as "Gnutella," which allows the computer to access thousands of other systems on the network. Once connected to the network, P2P software allows you to search for files on other people's computers. Meanwhile, other users on the network can search for files on your computer, but typically only within a single folder that you have designated to share. While P2P networking makes file sharing easy and convenient, is also has led to a lot of software piracy and illegal music downloads. Therefore, it is best to be on the safe side and only download software and music from legitimate websites. P2P is the most common way to share game, movies, and music over the Internet. 3272155-629285113030-657860Figure 3One of the advantages for Peer to Peer Networks are easy and simple to set up and only require a Hub or a Switch to connect all the computers together.it is inexpensive which is often free to set up and use. You can access any file on the computer as long as it is set to shared folder. The requirements for a Peer to Peer Network are that you have a 10 Base T Ethernet cable and an Ethernet hub/ switch. This is rather cheap than having a server. The architecture of the lay out (How It Connects) is simple. If one computer fails to work all the other computers connected to it continue to work. The disadvantages of P2P network is lack of security controls or other common management functions. Security is not good and you can set passwords for files that you don’t want people to access but apart from that the security is pretty poor. It doesn’t always work if you have many computers and works better with 2 – 8 computers. If you have not connected the computers together properly then there can be problems accessing certain files.Distributed Processing NetworkDistributed processing is a phrase used to refer to a variety of?computer systems?that use more than one?computer?(or?processor) to?run?an application. This includes?parallel processing?in which a single computer uses more than one?CPU?to?execute?programs.More often, however, distributed processing refers to?local-area networks (LANs)?designed so that a single program can run simultaneously at various sites. Most distributed processing?systems?contain sophisticated?software that detects idle?CPUs on the?network?and parcels out programs to utilize them. A communications network in which there exist alternative routings between the various nodes?(computer science). The Computer network in which at least some of the processing is done at individual work stations and information is shared by and often stored at the work stations.?In Distributed Processing Network, processing capability is located and shared at different nodes or locations. This type of strategy is common for decentralized organizations where divisional offices have their own computer organization’s main or centralized computer. Another form of distributed processing involves?distributed databases. This is databases?in which the?data?is?stored?across two or more computer systems. The?database system?keeps track of where the data is so that the distributed nature of the database is not apparent to?users.1390650-55689500 Figure 4Advantage?of Distributed Processing Network is it can drastically increase processing speed. Its one of the biggest advantage is frugality that it doesn’t leave processor of the computer idle. The task like screen saver or keyboard records your typing .Its basic function take very little power of the processor and rest of the power goes to waste .Another major pros is that it can take full advantage of all computer capabilities in performing calculations. Topology that is considered doesn’t change which makes distributed computing, a topology dependent. Band width is infinite which a one of the biggest drawbacks. Server computers are still needed to collect and combine the data which is transferred from clients involved in the network. Distributed Processing Network can be infinitely expandable which means just keep adding computers since it required large memory for its processing. Other than that, the security of the Distributed Processing Network is through redundancy.The disadvantage of the Distributed Processing Network is there is a lot of extra programming is required to set up a distributed system. All the computers on the Internet may be powerful when combined, but there needs to be something to combine and coordinate all of them to work towards one goal. Server computers are still needed to distribute the pieces of data and collect the results from participating clients. Collecting Internet users and having them sign up for a distributed computing program is not an automatic process where often times, organizations need to attract users with offers and incentives, from screensavers to cash payments. When dealing with a local distributed network — where the computers are within a contained area, such as a room — the cost of maintenance can skyrocket because each computer has its own share of problems and errors. Unless these computers are used for something else, say, as workstations at a library, this type of distributed computing isn't cost-effective.REFERENCES ................
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