Unformatted text preview: ng issues 5 Session Layer Requests a connection, as per the end user, to a network. Also responsible for disconnecting from the network. 4 Transport Layer - Breaks the message into blocks and is also responsible for monitoring quality of the communication channel. 3 Network Layer creates routing messages and is concerned with the networks that will be used to send data 2 Data Link Layer gathers bits data bits into a block and sent to the physical layer 1 Physical Layer - sends a bit stream over a transmission medium FIGURE 7-1: LAYERS OF THE OPEN SYSTEMS INTERCONNECTION MODEL FIGURE 7-2: TRANSFERRING A FILE UNDER THE OSI MODEL FIGURE 7-3: MULTIPLE NODE COMMUNICATIONS UNDER OSI Protocols and Standards Key elements of a Protocols are: Syntax: structure or format of data. ie. First 8 bits of data represent the sender's address, the next 8 bits are the address of the receiver and the remaining bits represent the message. Semantics: meaning of each segment of bits. Does an address tell us the route to be taken or does it de...
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- Spring '08
- Computer Networks, packet switching networks