DATA COMMUNICATION
Components of a computer network
Data communication is a medium for receiving and delivering data (Leondes, 2012). It is useful when a user wants to convey information within a particular place. It enhances the smooth flow of data communication. The data communication involves the conveyance of digital data to various electronic elements via a cabled or wireless connection.
The media for data communication are bound and unbound media. The bound media involves the transfer of data via physical connections. The network is useful in the conveyance of the signal from one device to the other external device. Cabling is helpful in computer s for sharing of files with other computers. These media offer a high-speed transfer of signals, and most companies consider it as reliable. The other type of data communication is unbounded media. This media refers to data communication, which works through networking different computers via a wireless connection. This media connects multiple computers without the usage of physical contact. The difference with the bounded is that the unbounded use air transmission. The channel can transfer files and share resources of the computer system (Stallings, 2014).
Network communication devices are different hardware tools that allow the transmission of information, data, and instructions between two devices. They transfer the analog and digital signal over separate device entities within a wireless or connected medium. This connection enables the computer to talk with one another. A computer evokes to process data as digital signals. The communication channel will then allow information, data, and instruction to conveyed along the chain as a digital or analog format. The signal of analog has continuous electrical wave unlike the digital signal which has pulses of electricity that represents bits. For the digital signal, the modem will transfer the signals between the devices and the channels of communication. The analog signal, it will use the modem which will convert first between the signals of analog and the digital. Example of network communication devices includes smartphones, Bluetooth, Network card, WI-FI, modem, and many others (Murthy, 2010).
The unbound media is the cheapest and best media transfer. The unbound channel cuts the cost of the cables that will be used to connect. It uses air transmission by connecting with various devices to share system resources. They offer the best communication networks that are useful in a wide area network (WAN). This network provides high bandwidth with a broader area of its transmission. It has a high frequency hence useful for a given activity (Stallings, 2014).
For a device, utilization of WI-FI device is essential. It allows the user to get connected with different methods within the network. It is cost effective when linked with other devices without the intention of a router. This WI-FI allows the router to be cordless (Murthy, 2010).
Network traffic organization.
Model of the data network is a database model that is in a flexible way of showing their objects and relationship. The different models of the data network are (Michael Duck, 2009)
OSI Model
OSI Model is a conceptual model that standardizes the functions of communication of the telecommunication system without considering the internal structures. This model gives a way in which data is sent from one user and received over the recipient network. OSI model provides communication with standards for the companies. The model has a series of seven layers. Each layer has a given responsibility in which given task is accomplished while receiving and sending data. The layers are essential to allow message reach a given destination.
Seven layers of the model
Layer 7 application
Application layer is the top-most layer. It offers a medium for the process of application to access the network of a computer. The application layer also establishes an error recovery and data integrity agreement and getting resources for the occurrence of communication.
Presentation layer
This focus on the data presented. It presents a layout that the data use in its transmission. It makes the data be understood and readable by the user.
Session layer
This session layer allows for two parties to communicate across the network. The layer handles the setup of data exchange, session, and termination of the session. Another significant value of session layer is that it offers flow control of communication between different computers
Transport layer
This layer deals with data transmission between networks of the various systems. The layer ensures there is n occurrence of error given to the specific user. Generation of address for receiving computer is done in the transport layer and adds to data to reach the required destination.
Network layer
In the network layer, smaller bits of data generated from a long message known as packets. The route data will be chosen together with the address of data delivery. The packs will travel in nodes on the network because of the addition of routing information and the destination address.
Data link
The data link transfers information from one computer to another. The layer formats messages on the details control physical layer and correct errors during transmission.
TCP/IP model
TCP/IP model is a conceptual model and a collection of communication protocols utilized on the internet and the same computer network. The model is beneficial in stating the duties of a communication system by splitting the procedures of communication into smaller components. It contains four layers namely (Stallings, 2014)
The link layer
The link layer is the lowest layer. The layer combines the data link layer and the physical layer into one entity. The layer performs line coding and synchronization process, error detection, and the MAC and LLC sublayer functions.
Internet layer
This layer follows the link layer. The layer is associated with the OSI network layer. The function of the internet layer is to offer traffic routing and control, session multiplexing, message reordering, and the acknowledgment. The standard protocols include user datagram protocol and the transport control protocol.
Application layer
The application layer is the highest layer of the model. The layer is related to the application, presentation, and the session layer of the OSI model. The application layer is beneficial in handling all the communication functions of the process to process. The layer also establishes sessions, terminates and maintains, data conversation, and encryption. The protocols used include SSL, SMTP, HTTP, and others.
Network addressing techniques
Network address refers to an identifier for a host on the system of telecommunication. The network address in this place is well designed to be a unique identifier in the network. The computers use network address to communicate, identify, and locate other computers. The network address is maintained to be unique across (Scott C -H Huang, 2010).
We have four different communication in the network
Unicast
Unicast is one-to-one communication. Each point contains a unique address. This addressing is considered to be predominant, which includes Http, SMTP, and FTP.
Broadcast
This type of communication uses one-to-all communication. The information flows from one scope to another network. The sender has a unique address, while the destination is 1. An example includes DHCP and ARP.
Multicast
Multicast is the type of transmission that uses a one-to-many method. The message sent from one point to different receivers on the other end. The receiver has to request for the information on the device. An example is UDP.
Anycast
This type of transmission uses one-to-one-of-many techniques. It is similar to multicast through the information sent to the recipient which in turns become a sender and sent to another group of receivers. This method is uses in the Domain Naming System
Purpose of common network protocols and standards.
Protocols are the rules that govern a particular entity, while standards is a certain level of quality. The guidelines communicate essential for the transfer of packets. The protocols help in the communication of devices, error detection, and the interaction of computers within the network. The TCP/IP is one of the standard protocol (Forouzan, 2013).
Having network protocols and standards in place will enable various devices from a different institution to communicate effectively with one another. It will, in result ease mode of communication between the devices.
The network standards are rules set in place by commission to ensure interoperability. Standards provide true compatibility among vendors. The standards enhance smooth communication among different vendors.
Methods of controlling access to network media
Media access is as a way in which computer grain, and it can control the network’s physical medium access. The purpose of media access is to help avoid Collison of packets. The access methods include (Mathur, 2010)
CSMA/CD: Carrier- Sense Multiple Access with Collision Detection
CSMA/CD is a protocol for transmission carrier in Ethernet networks. The device will start to transmit at its first frame. When another device starts simultaneously, a Collison will occur, causing frames to discard. The stations will then have to wait for a random length of the duration before looking at the capable then of retransmitting.
CSMA/CA: Carrier-Sense Multiple Access with Collision Avoidance
In this technique, instead of the computer detecting the collision and reacting on it, the CSMA/CA avoids them by ensuring the signal of machines are done to ascertain the purpose of transmission. Apple network is an example.
Token passing
The Collison are done away under the token passing. This token passing is the reason as to which only a computer with a free token is given a through pass to transmit. The transmission that emanates from the station with a high priority takes the eminence over the station that has lower priority. This type of token pass function best in the platform with a large number of data frames that are shorter, which are transmitted. The token passing is useful in the ArcNet Network and the Token ring.
The station that transmit on the network will have to wait until when we have a free token. The station will then send data transmission with the token. The token will proceed without stopping at the other stations. The recipient station will then receive.
Demand priority
This demand priority is the newest Ethernet media access technique that seems to replace older CSMA/CD. The demand priority has various characteristics that include
Prioritization of the transmission
Utilizes the 100 Mbps Ethernet
Needs a hub that is smart technology
The station can receive and transmit within the same duration
References
Forouzan, B. A., 2013. Data communications and networking. 5th ed. New York: McGraw-Hill.
Leondes, C. T., 2012. Database and data communication network. Systems techniques and applications. 2nd ed. Amsterdam: Boston Academic Press.
Mathur, N. B. L., 2010. Data communication and networking. New Delhi: Anmol Publications.
Michael Duck, R. R., 2009. Data communications and computer networks. 2nd ed. New Jersey: Harlow Pearson/Prentice Hall.
Murthy, C. S. V., 2010. Data Communication and Networking.. 2nd ed. New Delhi: Himalaya Pub. House.
Scott C -H Huang, D. M. D. D., 2010. Network security. 1st ed. New York: Springer.
Stallings, W., 2014. Data and computer communications. 10th ed. Boston: Pearson.