OSI and TCP/IP

The OSI model is a model which explains the way computers communicate with each other over a network; it uses a seven layered approach to transmit data, the layers being physical, data link, network, transport, session, presentation and application, the data flows down the transmit layer over a physical link, and finally passes through the receiver layer. The TCP/IP is also a layered model but does not use all of the layers as in the OSI model, the network protocol model is similar to layer 3 of the OSI model, the combination of the 5^th, 6^th and 7^th layers of the OSI model is similar to the application layer and the host-to-host layer is similar to the 4^th layer of the OSI model. A fiber media convertor is a networking device used to connect two media types which are not similar like a twisted one with fiber optic cable, they are significant in connecting fiber optic cable systems with the already existing copper based systems and the structured cabling systems.

          A network address is used to identify a computer on the network, when used properly computer can find the addresses of added computers on the same network, and can be used to send messages to these computers, the most used example of a network address is the Internet Protocol (IP) Address. The network protocol is a set of rules which a computer follows when data is exchanged in a computer network, a few examples of network protocols are FTP, HTTP, SMTP, Telnet, HTTPs, Bluetooth, OSI and RTPS protocols etc,. WAN (Wide Area Network) is a network that covers a larger area which uses telecommunication lines that are leased. LAN (Local Area Network) is a network used to connect computers in a small area which maybe at home, office or a computer lab for example, an Ethernet. Network security is the steps or approaches taken by a network administrator to avoid misuse, illegal access to the network, and ability to modify a computer network. Tools that are used for network troubleshooting are very important for every administrator to troubleshoot different conditions of working some of the troubleshooting tools are Ping, IPConfig, Trace route, Netstat, NS lookup, Subnet, Netstat, Mtr and Route. All the above discussed topics are extremely important to understand the working, data exchange and networking of a computer.

          Data communications and Network systems are used for computers to communicate with each other, computer networking systems are widely used in many fields like accounting, sales and many others, the job of a system analyst it to communicate with other computer systems for sharing information among them. Email and internet are most extensively used at homes, offices and in individual businesses, designing the hardware and software for computer usage for data exchange is a part of data communications and Network systems. The growing demand for computer analysts who have in depth knowledge in Data communications and Network systems itself is proof enough that internet and email play a major role in everyday life.