Computer Communications & Networks Lab Report Example | Topics and Well Written Essays - 2000 words

Computer Communications & Networks - Lab Report Example The devices are called end devices or more correctly hosts; which are either the destinations or sources of information transmitted via a network so accessing a network or site remotely involves three elements; a source or sender, a destination and a medium which is the channel through which the data is transmitted. The data transmitted can be in the form of text, graphics, voice or video which are converted into a language the computer understands called binary bits (data is transmitted as a zero or a one: 0I). The bits are then ‘programmed’ or coded into signals or data packets that can be transmitted through a medium over a network. Now sending data as one continuous stream will mean that no other data or devices can use the medium while the data is being transmitted just like a pipeline; if it is delivering gasoline, it cannot at the same time deliver liquid petroleum gas; so the data is broken into smaller packets; a process called segmentation which allows many dif ferent data to be transmitted concurrently, this is called multiplexing and segmenting data enhances network reliability so data is not lost easily whenever a break in communication occurs (â€Å"3rd Symposium on Networked Systems design and Implementation (NSDI’06), San Jose, California†). ... The one used for internet communication is called TCP/IP stack which contains four layers; Application protocols layer that is defined to applications like WWW, or FTP (File Transfer Protocol), a transmission control protocol which is responsible for directing packets of data to specific computers by using a port number. It also has an internet protocol layer that directs data bits to destinations using the IP addresses of the computers and a hardware layer that converts data into data streams or signals such as the network cards or modems. An instruction flows from the sender (computer) from the application to the transfer control protocol then to the internet protocol and finally to the hardware protocol that converts the bits of information into signals transmitted through a medium through the internet. On reaching the destination computer, the signals are converted back to binary bits through the hardware layer then to the internet protocol layer then to transfer protocol layer a nd then to the application such as a web server software. The internet is made up of many big networks called Network Service providers (NSPs0 connected together in a peer standard. The NSPs exchange data packets with each other and must connect to three network access points (NAPs) and at metropolitan Area Exchanges (MAEs) both of which are called internet exchange points (IXs). Information is then sent around these networked computers to its destinations by routers which contain information tables and switch data packets to the right destination (Serpanos and Wolf 292-302) As soon as one types the web address to be accessed into a web browser (a web browser is a program that is used for internet applications and