The 20th century has seen tremendous changes in telecommunications sector where there has been great improvement in communication. The major examples of telecommunications sectors which have greatly developed over the century are computer communication, telephony and telegraphy. There has also been a major revolution in the communication media being used in interconnecting the communicating gadgets. However, some media have remained dominant and still hold a significant role in contemporary telecommunications sector (William, 2007).
Narrowing down to computer networks, they can be defined as a collection of interconnected nodes (end devices). Much precisely, a network is a medium that allows passage of data across from one machine to another. The data can be digital signals, voice or even analog signals. From this description, it is clear that a network must have: communicating devices (nodes), the interconnecting medium (copper cables, fiber and air), rules to adhere to during communication (protocols) and intermediate devices (routers, switches). These necessities form the basic features of any network (William, 2007).
Having looked at the basic features of a network, computer networks fall mainly in two categories described by models. These two models are the OSI model and the TCP/IP model. A look at the two models reveals that each model has some distinct traits that make it either suited for dedicated transmission (circuit switching) or packet switching. OSI (open systems interconnections) model is a 7 layer model that has each layer playing a particular role in the communication process. The topmost layer is the application layer that contains the data to be sent or decodes the data to a form that can be interpreted by the user. The second layer is the presentation layer. This layer creates independence of application process from some browser syntactic. It allows the application layer to use any suitable editor without having to affect the other layers. The third is the session layer which establishes and closes any connection to the transport layer. The fourth layer is the transport layer. This is the layer responsible of ensuring that the data has been sent from the source to destination. The fifth layer is the network access layer. As the name suggests, this layer establishes, maintains and manages all the network connections. The sixth layer comes by the name data link layer. This layer is the one responsible of data synchronization, error control and flow control. The bottommost layer is the physical layer. It provides for the physical network connections (internet port connector). The second model, TCP/IP, is the most dominant since almost all networks use packet switching based technologies like ATM and frame relay. This model has 5 layers. The topmost layer is the application layer. This layer operates in a similar version as that in OSI model. The second layer is the transport layer. This layer allows for host-to-host communication. It covers the tasks accomplished in presentation, session and part of transport layers in the OSI model. The third layer is the internet protocol layer. This layer allows for communication across networks making the model to have both peer connections and internetworks connection. The other layer is the network access layer. This layer operates similarly as that in OSI but has added tasks as it accomplishes both network access and data link tasks. The last layer (bottommost) is the physical layer which allows for physical connection to the network media (William, 2007).
Trying to postulate of the future, the ancient telephone networks are rapidly getting replaced by better technologies like fiber and wireless communication media. These media have a higher data capacity and larger bandwidth compared to the telephone networks which have a very narrow bandwidth and consequently low speeds. Also, telephone networks are more of peer to peer connections and most of the clients in computer networks are mobile. This makes them require a flexible access medium like a wireless connection. A look at computer networks indicates a great deal of evolution from telephone wire based networks which were slow and with limited transmission capabilities to faster and more flexible media like the fiber cable. A look into the future of this communication network reveals that due to flexibility every connection might be flexible. The connections also appear to target the clients’ needs and specifications. This can be termed as the reason of having networks like LANs and CANs. This postulates that telephony will soon become internet based (VoIP services) while the communication media will improve on speed and immunity against factors like electromagnetic radiations (Gordon, 2004).
Taking a look at the networks under use in the contemporary IT world, they can be divided into three categories. The first category is the local area network (LAN). This network covers only a small geographical location usually a single building or a few building. The issue of network security in this network is not a major problem since security threats are very low. The second network is the metropolitan area network. This network mainly covers a city or equivalent geographical area. Usually, this network offers high speed connection and the network equipment is owned by the ISPs operating in the area. The last network under intense is a collection of interconnected MANs and LANS. This is the wide area network (WAN). The internet falls under this category and goes beyond any national boundaries (Gordon, 2004).
Taking a look at use of internet in the contemporary business world, businesses rely on the internet heavily. The first example is by offering VoIP services. These services allow for people or businesses communicate with their clients effectively at relatively cheap rates. This also allows for the people to have confidential talks which hacking or wire tapping cannot be done effectively. Another example of application of internet services is online business transactions. This has evolved in form of e-commerce which currently appears to have taken root in all sectors of the economy. For this reason, people from different parts of the world can shop abroad, pay and monitor delivery of the ordered goods from the comfort of their business premises. The third application of internet is sale promotion. The key importance of internet is its ability to convey information. Therefore, a business puts its product features online and since millions of people visit the internet daily, the target group reached per unit time is high. The cost of promotion is relatively cheap (Gary, 2003).
In conclusion, networking in computers allows sharing of information. This allows for internal sharing, international sharing and even other services like teleconferencing. As technology is shifting and communication becoming more internet-based, security is becoming an issue leading to use of CANs which allow specific clients to access the resources (Gary, 2003).
References
William S. 2007. Data and computer communications, Pearson Inc, 8th edition
Gordon B. 2004. Computers in communication, McGraw-Hill International (UK)
Gary T. 2003. The internet, MIT press
