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Funny Love Song (About OSI Model)
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| gcw123 2003-02-21, 9:27 am |
| The OSI Reference Model is based on a proposal developed by the International Organization for Standardization (ISO). The model is called ISO OSI (Open Systems Interconnection) Reference Model because it deals with connecting open systems - that is, systems that are open for communication with other systems.
The OSI model has seven layers. The principles that were applied to arrive at the seven layers are as follows:
1. A layer should be created where a different level of abstraction is needed.
2. Each layer should perform a well defined function.
3. The function of each layer should be chosen with an eye toward defining internationally standardized protocols.
4. The layer boundaries should be chosen to minimize the information flow across the interfaces.
5. The number of layers should be large enough that distinct functions need not be thrown together in the same layer out of necessity, and small enough that the architecture does not become unwieldy. | |
| gcw123 2003-02-21, 9:30 am |
| The seven layers of the OSI Basic Reference Model are (from bottom to top):
1. The Physical Layer describes the physical properties of the various communications media, as well as the electrical properties and interpretation of the exchanged signals. Ex: this layer defines the size of Ethernet coaxial cable, the type of BNC connector used, and the termination method.
2. The Data Link Layer describes the logical organization of data bits transmitted on a particular medium. Ex: this layer defines the framing, addressing and checksumming of Ethernet packets.
3. The Network Layer describes how a series of exchanges over various data links can deliver data between any two nodes in a network. Ex: this layer defines the addressing and routing structure of the Internet.
4. The Transport Layer describes the quality and nature of the data delivery. Ex: this layer defines if and how retransmissions will be used to ensure data delivery.
5. The Session Layer describes the organization of data sequences larger than the packets handled by lower layers. Ex: this layer describes how request and reply packets are paired in a remote procedure call.
6. The Presentation Layer describes the syntax of data being transferred. Ex: this layer describes how floating point numbers can be exchanged between hosts with different math formats.
7. The Application Layer describes how real work actually gets done. Ex: this layer would implement file system operations. | |
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| gcw123 2003-02-21, 9:36 am |
| The OSI Reference Model is based on a proposal developed by the International Organization for Standardization (ISO). The model is called ISO OSI (Open Systems Interconnection) Reference Model because it deals with connecting open systems - that is, systems that are open for communication with other systems.
The OSI model has seven layers. The principles that were applied to arrive at the seven layers are as follows:
1. A layer should be created where a different level of abstraction is needed.
2. Each layer should perform a well defined function.
3. The function of each layer should be chosen with an eye toward defining internationally standardized protocols.
4. The layer boundaries should be chosen to minimize the information flow across the interfaces.
5. The number of layers should be large enough that distinct functions need not be thrown together in the same layer out of necessity, and small enough that the architecture does not become unwieldy. | |
| darklumina 2003-02-24, 12:29 am |
| If you are going to post shockwave movies with pictures of yourself in it.. at least put on some decent make up   |
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