OSI MODEL Essay -- essays research papers

Michael Rauseo IT310 OSI ModelIn the premature years of computer and network research and development many systems were designed by a number of companies. Although each system had its rights and were sold crossways the world, it became apparent as network usage grew, that it was difficult, to enable all of these systems to exit with each other.In the early 1980s, the International Organization for Standardization (ISO) recognize the need for a network model that would help companies create public network implementations. The OSI reference model, released in 1984, addresses this need. The OSI reference model became the primary architectural model for converses. Although other architectural models have been created, most network vendors denote their network products to the OSI reference model.The OSI model describes the processes necessary for effective communication in terms of a seven spirit leveled model. The seven floors are somatogenetic gradeThe somatogenetic floor defines the electrical, mechanical, procedural, and functional specifications for activating, maintaining, and deactivating the physical link amidst end systems. Such characteristics as voltage levels, timing of voltage changes, physical data rates, maximum transmission distances, and physical connectors, are defined by physical layer specifications.Data Link LayerThe data-link layer turn ins error-free transferral of data frames from one computer to another over the physical layer. The layers higher up this layer can assume virtually error-free transmission over the network. The data-link layer provides the following functions. - Establishing and terminating a logical link in the midst of two computers set by their unique network interface card. - Controlling frame settle by instructing the transmitting computer not to transmit frame buffers - sequentially transmitting and receiving frames - Providing and expecting frame-acknowledgment, and detecting and recovering from erro rs that occur in the physical layer by ret... ...cation layer of one system will be percipient by the application layer of another system. If necessary, the entry layer translates between multiple data representation sets by using a third estate data representation format. The presentation layer concerns itself not only with the format and representation of actual user data, but also with data structures utilise by programs. In addition to actual data format transformation, the presentation layer negotiates data transfer syntax for the application layer.Application LayerThe application layer is the OSI layer closest to the user. It differs from the other layers because it does not provide services to any other OSI layer, but rather to application processes prevarication outside the scope of the OSI model. Examples include spreadsheet programs, word-processing programs, banking terminal programs, etc. The application layer identifies and establishes the availability of intende d communication partners, synchronizes cooperating applications, and establishes agreement on procedures for error recovery and control of data integrity. Also, the application layer determines whether sufficient resources for the intended communication exist.