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Osi Model Explained experimentThis paper discusses the Open System Interconnection reference framework (OSI influence) and the organization and function of its 7 points. The OSI model is the most commonly referenced networking communication model, but it is r arely implemented in its entirety Ciccarelli et al. (2008). The OSI model provides a common frame of reference for discussing various hardware and software issues (Ciccarelli et al., 2008). The layers are the Application, debut, Session, Transport, Network, Data affiliate and Physical (Ciccarelli et al., 2008). When selective information is sent, the user application sends data pass by dint of the layers of the model, which are self contained and pose specific functions. Each layer adds information to the data pertaining to the layers control. The OSI model was created in 1984 by the International Standards Organization (ISO) in response to the need for a set of standards to allow computers to communicate through a network according to Ciccarelli et al. (2008).Additional rationales for the OSI model are given and most significant among them is that it was knowing to overcome interoperability issues with networking products from disparate vendors (Ciccarelli et al., 2008 Davis, 2008). Other reasons given for creating the OSI model include to clarify general functions of internetworking (Rivard Roherty, 2008) to divide the complexity of networking into smaller more make outable bites (Rivard Roherty, 2008) to simplify troubleshooting (Ciccarelli et al., 2008) to allow developers to change and improve components of a networking stack without repair the function of other layers (and the need to re-write them) (Rivard Roherty, 2008)A key to the understanding the OSI model is the idea of data flip down through the OSI model layers in one computer, whence across a network media and then up through the OSI model layers in a second computer (Hill, 2002). As data flows down through the OSI model layers, each layer that has an applicable communications protocol, labels the data packet with a headland and a radio-controlled aircraft specific to the layer this is known as encapsulation (Hill, 2002). On the recipient computer, the data header and trailer is removed after its values are utilized (or de-encapsulated) as the data packet travels up the agree layer of the OSI model (Ciccarelli et al., 2008 Hill, 2002). Each layer prepares the data for the adjacent layer before it is forwarded by adding header and trailer data to the data. Layer responsibilities and definitions(7) Application User programs communicate with APIs in the application layer which allows user programs to contain very little networking code themselves (Hill, 2002). The application layer provides access to the network protocol stack. DNS run fors at the application layer. Other important examples of protocols operating at this layer are http, POP3 (email protocol), SMTP (email transport protocol), IMAP (internet pith access protocol), FTP and Telnet includes network printing and database services. Layer devices include hosts, servers, PCs and laptops, cellular phones pic(Ciccarelli et al., 2008 Hill, 2002 Messer, 2010). (6) Presentation This layer vouchs that format of data input from the application layer is in a form competent for transport over the network, and that it can be interpreted by the receiving thickener. Translates character sets such(prenominal) as ASCII, EBCDIC and Unicode for compatibility with a trend nodes. This layer compresses and encrypts data as needed pic(Ciccarelli et al., 2008 doogie966, 2011 Hill, 2002 Messer, 2010).(5) Session Sets up, maintains and breaks-down connections between network endpoint applications negotiates whether transmission leave be simplex, half-duplex, or bounteous duplex. Simplex is similar to a broadcast in that it is one way half-duplex is two way transmission, but only one direction at a time full duplex is two-way communication at the same time using different channels to manage send and receive traffic pic(Ciccarelli et al., 2008 Hill, 2002 Messer, 2010 Rivard Roherty, 2008). Remote procedure calls originate from the session layer (doogie966, 2011). (4) Transport Provides accredited transport using connection-oriented services (transmission control protocol -TCP) and connection-less oriented services (user datagram protocol, or UDP). Important functions provided by this layer are flow control, error detection and error recovery. Flow control starts before data is actually sent. The transmitting node sends the receiving node a message indicating that it is about to transmit data to the receiving node.The receiving node acknowledges the receipt of the notice from the sender then data is transmitted. Flow control utilizes TCP protocol to ensure delivery of data. TCP is associated with connection-oriented service where communication is assured. Flow control also manages data transmission rac e through a windowing process. A TCP window is that specific amount of data that can be sent before an acknowledgement is required by the receiving node. This prevents the receiving device from being overwhelmed by data lot that is cant process fast enough. Connection-less transmissions (UDP) offers no error detection or recovery utensil and is faster without the overhead of recovery requirements pic(Ciccarelli et al., 2008 Hill, 2002 Messer, 2010 Rivard Roherty, 2008). (3) Network responsible for(p) logical addressing using IP protocol, or thoroughfare determination (routing) and packet (datagrams) delivery pic(Ciccarelli et al., 2008 Hill, 2002 Messer, 2010 Rivard Roherty, 2008).When traffic arrives at the network layer, header/trailer information is added or taken away that includes the logical addressing data or IP. IP addressing allows a router to route packets to remote nodes IP. there are two ways routing can be processed one is consultation routing. In quotation r outing, IP data for every router on the path to the destination is included in the data packet. The routing mode calls for the source and destination IP information to be contained within the packet. Once on the network, routers use the source and destination addresses to forward the packet to the next router, or hop, on the path to the destination (Ciccarelli et al., 2008). (2) Data middleman Consists of Logical Link Control Layer and the Media Access Control Layer MAC layer Responsible for physical addressing or for getting traffic onto the network using the MAC protocol, this layer is responsible for NIC (L1L2) control.Switches and link operate at this layer, since they are using the MAC physical address of the sender/receiver devices to baffle which port on a switch to use, or whether to let traffic pass (bridge). Switches also operate at layers 3 and 4 pic(Ciccarelli et al., 2008 Hill, 2002 Messer, 2010). Media access control (MAC Address) addressing is managed and added/re moved from traffic at this layer. Logical addresses (IP) are not considered at this layer. LLC sublayer bridges the MAC sublayer to the upper layer protocols. 1) Physical Responsible for physical devices such as NICs(L1 2), cabling, fiber, coax, wireless, hubs, connectors (e.g. RJ-45, BNC and for implementing standards for physical configuration of connectors such as TIA/ETA (RJ-45). Also, the physical layer manages signaling and voltages required to transmit data pic(Ciccarelli et al., 2008 Hill, 2002 Martin, Not Given Messer, 2010).ReferencesCiccarelli, P., Faulkner, C., FitzGerald, J., Dennis, A., Groth, D., Skandier, T., Miller, F. (2008). Networking Basics. Hoboken, NJ John Wiley Sons, Inc. Davis, D. (2008). Cisco Administration 101 pick up the OSI model to become a better Cisco troubleshooter. Retrieved 2/13/2013, 2013, from http//www.techrepublic.com/blog/networking/cisco-administration-101-understand-the-osi-model-to-become-a-better-cisco-troubleshooter/556 doogie966. (20 11). OSI protocols and devices. from http//quizlet.com/6089965/osi-layer-protocols-devices-flash-cards/ Hill, B. (2002). Cisco The ace Reference McGraw-Hill/Osborne Media. Martin, U. o. T. a. (Not Given). EIA/TIA 568A 568B Standard. Retrieved February 16, 2013, from http//www.utm.edu/staff/leeb/568/568.htm Messer, J. (2010). The OSI Model CompTIA Network+ N10-004 4.1. Retrieved February 14, 2013, from https//www.youtube.com/watch?feature=endscreenv=W438koUR04oNR=1 Rivard, E., Roherty, J. (2008). CCNA Flash separate Practice Pack (Third ed.) Cisco Systems, Inc.