Network Security Essay

Since the last two decades there has been an overwhelming increase in the number of organizations that rely on data communication networks for their daily business communications, resource sharing, database information retrieval so on and so forth. Previously most computers were centralized and managed in data centres. Computers were kept in locked rooms and links outside a site were unusual. Computer security threats were rare, and were basically concerned with insiders. These threats were well understood and standard techniques were used to deal them. The scenario has changed and now systems are connected to the Internet. The Internet is a network of networks and has no boundaries whatsoever. The Internet provides these organizations with a world of business opportunities. Information on the Internet can be accessed from anywhere in the world, unfortunately it has also allowed for the â€Å"proliferation of malicious information†. It does not take long for an expert programmer to break into a system. The value of the data stored on most organizations’ networks and the value provided by the application systems in use far exceeds the cost of the networks themselves. Network security has become of the most important issues for these business organizations and aims at protecting the organizations’ data and application software. What is Network? A â€Å"network† has been defined as â€Å"any set of interlinking lines resembling a net, a network of roads an interconnected system, a network of alliances. † This definition suits our purpose well: a computer network is simply a system of interconnected computers and peripherals. Essentially there are three basic hardware components of a data communication network. Server: The server or the host computer houses all the data and the software that is to be accessed by the clients. Client: A client can be referred to as an input/output hardware device that lies at the other end of the communication circuit. It enables the user to have an access to the network and the data and software on the server. Circuit: The circuit is the route or the medium through which the message travels. Nowadays the fibre optic cable and wireless transmission are becoming increasingly common. A peer-to-peer network lacks a central server. There is a set of computers, which are linked together by a cable. Each computer is an equal, or â€Å"peer,† of the others, and has the ability to share the files and peripherals of other computers that are connected to the network. This type of network is essentially designed for a very limited number of users (five or less) in a business organisation. Some of the benefits of a peer-to-peer network are low-cost and easy-to-install solution. If anyone of the user turns of its workstation the other users are not able to access this particular user’s information and peripherals. Furthermore, accessing data and applications from another person’s workstation can cause performance problems for that user. Client/Server Networks Client/server networks are a lot more than peer-to-peer networks. The presence of a dedicated server in the network ensures that the users are able to access information and share peripherals without being dependent upon other user(s)systems. There is room for installing a tape backup that enables the users to back up data on both the server and all workstations. Client/server networks are primarily used when there is a constant need to access large files and applications or when peripherals have to share between a numbers of users. Thin-Client Computing Thin-client (server-based) enables centralized application deployment and management on a server. Because of this technology system updates and maintenance can be done on an enterprise-wide level instead of on a physical desktop-to-desktop basis. This not only enhances the productivity and efficiency of both end users and system administrators, but also lowers the total cost incurred. http://www. premiopc. com/networking/types/default. html Need of Security over Business Networks There are certain things in any business, which must be kept, confidential and secure. With the use of computers, everything is now on PC and PCs when connected to each other become vulnerable to many threats. The most common threats discussed below: Business Network Threats and Their Effects There are essentially two kinds of network threats that business organizations have to guard against: Disruptions Disruptions can be referred to as loss or reduction in network service. For instance a network switch might start malfunctioning leading to a breakdown of a part of the network. Although the part that has not been affected will be functioning perfectly, but the organization will have to replace immediately otherwise there would be a loss in employee productivity. For example finance manager failing to retrieve the information regarding the upcoming project. A virus could also lead to disruptions. For instance, an employee opens an email from an unknown sender. A virus could prove to be very fatal and may result in loss of valuable time on part of the employees(s). Natural calamities can also lead to disruptions. Fires, flood and earthquakes are common examples. It is good idea not to have company headquarters in areas that are vulnerable to such calamities. Unauthorised Access Unauthorised access is basically gaining access to organizational data files and resources, which you are not supposed to have an access to. Common term used for such offenders is hackers. Unfortunately in most of the cases the hackers are organizations’ own employees and can do a significant amount of damage to the organization if that valuable piece of information is leaked to organization’s close competitors. If the hacker happens to be a competitor, he can do an unimaginable amount of damage to the organization. He could access all the information regarding the latest products, which are under development, sales figures, company’s strength and weaknesses, financial position, future plans and a lot more. There are several types of unauthorized access. They are discussed briefly discussed.