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Osi Model

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This paper will discuss the Open System Interconnections (OSI). “The OSI was developed by the international Organization for Standardization (ISO) as a Model for a computer protocol architecture and as a framework for developing protocol standards. The OSI model consists of seven Layers: Application, Presentation, Session, Transport, Network, Data Link, and Physical.” (University of Phoenix) The Application layer supports application and end user processes, also it provides application services for file transfer, e-mail, and other network software service. Telnet and FTP are applications that exist completely in the application level. The Presentation layer provides self-rule from differences in data representation by translating from application to network format and vice versa. This layer works to convert data into the form that the application layer can accept. It formats and encrypts data to be sent across a network, providing lack of restrictions from compatibility problem. The Session layer launch manages and come to an end connection between applications. This layer sets up, brings together, and terminates conversations, exchanges, and dialogues between the applications at each end. The Transport layer provides crystal clear transfer of data between end systems, or hosts, and is responsible for end to end error recovery and flow control. This layer guarantee complete data transfer. The Network layer offers switching and routing technologies, creating logical paths, known as virtual circuits, for transmitting data from node to node. The routing and forwarding are functions of this layer, as well as addressing, internetworking, error handling, congestion control and packet sequencing. The Data-Link is where data packets are encoded and decoded into bits. The Physical layer communicates the bit stream – electrical impulse, light or radio signal through the

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