The OSI model is a model for understanding and designing a network architecture that is flexible. It is a layered famework which allow communication across all types of computer systems. It consist of seven separate layers which define a segment of process of moving information across a network. The OSI model provides the basis ofor exploration of data communication.
The seven ordered layers of OSI model are :
1. Physical Layer
2. Data Link Player
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer
When a message travels from one device to other, it travels through different intermediary nodes. These intermediary nodes usually involves the first three layers of OSI model.
At first layer the entire package is converted to a form that can be transferred to the receiving machine. At the receiving machine, the message is unwrapped layer by layer,with each process receiving and removing the data meant for it.
The passing of data anf information through the layer is made possible by an interface between each pair of adjacent layers.
The seven layers further divided in three subgroups.
Layers 1,2 & 3 physical,data link and network layer are network support layers. They deal with the physical aspect of moving data from one device to another.
Layers 5,6 & 7 session,presentation and application layer are user support layers. They allow the interoperability among the softwares.
Layer 4 transport layer ensures the end to end reliable data transmission whereas the data link layer ensures reliable transmission on a single link.
The upper OSI layers are used in softwares.
The lower layers are combination of software and hardware, except physical layer which is mostly hardware.
The seven ordered layers of OSI model are :
1. Physical Layer
2. Data Link Player
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer
When a message travels from one device to other, it travels through different intermediary nodes. These intermediary nodes usually involves the first three layers of OSI model.
At first layer the entire package is converted to a form that can be transferred to the receiving machine. At the receiving machine, the message is unwrapped layer by layer,with each process receiving and removing the data meant for it.
The passing of data anf information through the layer is made possible by an interface between each pair of adjacent layers.
The seven layers further divided in three subgroups.
Layers 1,2 & 3 physical,data link and network layer are network support layers. They deal with the physical aspect of moving data from one device to another.
Layers 5,6 & 7 session,presentation and application layer are user support layers. They allow the interoperability among the softwares.
Layer 4 transport layer ensures the end to end reliable data transmission whereas the data link layer ensures reliable transmission on a single link.
The upper OSI layers are used in softwares.
The lower layers are combination of software and hardware, except physical layer which is mostly hardware.
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