Data Communications and Computer Networks - Report Example

Networking 14th Nov Subject: For the communications to take place on the network, a standard based network system is in place which takes into account all the necessary factors. This system and standard is known as Open System Interconnect which is a proprietary entity and it sets the rules and protocols for the communication. O.S.I is a multi facet network layer that has all the necessary components which ensure successful operations of communication between two nodes or networks that might be hundreds of miles away from each other. The following are the layers involved in the O.S.I model: Physical layer: This is the lower most layer and contains the data in most simple and crude form. The bits so received in the first stage are handled in this phase and through the pulses are forwarded for further processing. It serves as the foundation brick between the physical world and the computer itself. Data Link Layer: By this phase the bits are converted into frames which are to be further converted into other format for the network layer. The transmission between hops is handled through data link layer and in form of frames. Data Link layer is concerned with the physical addresses. Token Ring and Ethernet are related to this layer. Network Layer: This is the layer where the data is fully integrated and converted into packets. By this time the destination is identified and authentic communication is in place. Logical addresses are handled in this phase. Path determination is another aspect that is handled by the network layer. To prevent saturation and congestion, this layer ensures all the mechanism processes needed to maintain the protocols. Transport Layer: Transport layer serves as the medium between upper three layers and the lower three. As the name implies, it is responsible for the transportation of packets between the nodes. Acknowledgment is also ensured in this layer. Session Layer: Synchronization is very important for the flow of data between any two respective ends. Session layer is primarily designated for this function and enables synchronization between two nodes involved in transmission. Presentation Layer: The kind of format that is suitable for the representation and processing of data is performed at the presentation layer. Encryption and decryption are also two important functions that are conducted by the session layer. It conducts the packet nature transfer according to the need. For the outside world, it converts it into simple language while for the technical inner operations it enables the appropriate steps. ASCII is an example of this layer (Kozierok, 2005). Application Layer: This layer serves as interface for final representation. All the applications that we see are the processing of application layer. H.T.T.P, F.T.P is few of the formats that are handled and supported by this layer. These seven layers together have all the necessary features which are required for conducting the safe and secure operations across the network. Telephone networks are operated over the circuit switch networks, while the computer networks are packet enabled. Most of the communication in modern times is being held over computer networks. Hence they are bound to stay. However the landline connections would not go down completely. They will have their role in their own right, but computer related and packet switched networks will get more dominant in times to come. There are basically three types of media involved in conducting communication via wires. While the wireless means has been dominating the world of communications all over, yet the wired medium is not out of the trend as yet. Mostly the last mile communication is held via the wired interface. The wired ones are following: Twisted pair cable: These wires are twisted in appearance; this twist is for the purpose of preventing any cross talk and other interferences and disturbances. They are further divided into two categories, the shielded cable and unshielded ones. They have different categories amongst themselves which are used for different purposes and have their own strengths over others. Coaxial cable: It is made up of copper. The basic form of wire, mostly used in the television sets connection. Ethernets are mostly connected via coaxial cables. They are good at resisting the interference and radio waves attenuation. They can work well within the range of up to 100 feet. Optic Fiber: This is the latest form of wired communication support medium. It has more resistance in terms of the noise and it also provides wider range of connectivity. They are more protected against the noise and other distortions. They are double layered in structure. It has the core, cladding and jacket part that separates these three units and allow improved performance. They are further divided into single mode optic fiber and multi mode optic fibers (Crisp, Elliott, & Elliott, 2005). LAN: Acronym for Local Area Network. They are mostly deployed in the office environments where multiple computers are connected to single main network that provides connection to the other sub connected systems. Their scale is usually low and limited to functionality within the premises. Numbers of computers are controlled through the LAN and the LAN computer itself is connected to the main source that provides connection to each of them. Multiple devices are being used in this setup, the simple networks require small number of devices to be used. RJ 45 wires are mostly used for the inside the building connections being established by LAN. Ethernet is a prime example of LAN technology. It is further segmented into Giga bit Ethernet and Fast Ethernet which have their own capacities and capabilities. WANS: Acronym for wide area network. Its range is relatively larger and cover large area. The range of WAN can be stretched to over kilometers of range. LAN and CAN can be categorized under the category of WAN since WAN has large scope of working. MANS: Acronym for Metropolitan Area Network. As the name implies it can function across the cities and have large range. Hundreds of systems can be attached under its umbrella. They provide high speed data transmission. Their range, capacity and service is relatively lower than that of Wide Area Network which covers large number of clients. It can enable supporting and connecting multiple local area networks. CAN: Campus Area Network: usually dedicated to working with in a campus which can be an engineering based company, a university campus, a large sized library or other resource such as Hot spots in the cities. It is basically built over connecting a number of LAN setups in a fixed locality. Their working capacity is lower than that of MAN and Wide area Network (White, 2010). Internet services are being used in most of the operations these days. All the networks are connected on wireless medium. VOIP is one of them. VOIP acronym for Voice over I.P is a modern day communication method that enables faster, reliable and long range connectivity. It can support heavy duty functions. It is predominantly used for the purpose of digital transmission. While the data travels as digital, it is conveyed as voice signal at the other end. It can be broadly termed as phone usage through the help of internet. It requires high speed internet connection to establish a call (Kelly, 2011). They have become the hot favorite in recent times, one of the reasons being its low costs calls across the world. All the communication is conducted over the Internet Protocol. Works cited: Crisp, J., Elliott, B. J., & Elliott, B. (2005). Introduction to Fiber Optics. Elsevier. Kelly, T. V. (2011). VoIP For Dummies. John Wiley & Sons. Kozierok, C. M. (2005). The TCP/IP Guide: A Comprehensive, Illustrated Internet Protocols Reference. No Starch Press. White, C. M. (2010). Data Communications and Computer Networks: A Business Users Approach. Cengage Learning. Read More