Reference no: EM131011089

OSI Reference Model:-

The seven layers of the OSI model are as follows:

• Physical layer:Converts the data into the stream of electric or analog pulses that will actually cross the transmission medium and oversees the transmission of the data
• Data Link layer:Provides an interface with the network adapter; maintains logical links for the subnet
• Network layer:Supports logical addressing and routing
• Transport layer:Provides error control and flow control for the internetwork
• Session layer:Establishes sessions between communicating applications on the communicating computers
• Presentation layer:Translates data to a standard format; manages encryption and data compression
• Application layer:Provides a network interface for applications; supports network applications for file transfer, communications, and so forth

TCP/IP Protocol Architecture

TCP/IP protocols map to a four-layer conceptual model. The four layers of model are: Application, Transport, Internet, and Network Interface. Each layer in model corresponds to one or more layers of the seven-layer Open Systems Interconnection (OSI) model.

The APRANET initially started with four Internet message processors (IMPs), located at the UCLA, UCSA, Stanford research institute and the University of Utah. In the early years, the purpose and usage of the APRANET network was widely discussed, leading to many enhancements and modifications as the users steady increased and requested demanded more from the network. As time passed many enhancements were made to the existing protocol but by 1973 it was clear that NCP (Network Control Protocol) was unable to handle the volume of traffic passing through it network and proposed a new functionality. A new protocol TCP/IP Transmission Control Protocol / Internet Protocol was developed over time to replace NCP.

Difference between TCP/IP and OSI Model