I want to know the layers in TCP/IP protocol suite and difference between TCP/IP and OSI model.
OSI (Open Systems Interconnection) is a well-recognized model to describe the mechanisms used for computer systems and network devices to communicate and it is commonly used as a foundation to other networking protocols, such as TCP/IP.
The best brief definition I have seen for OSI is from Newton?s Telecom Dictionary, an essential telecom reference book.
"The OSI model organizes the communications process into seven different categories and places these categories in a layered sequence based on their relations to the user. Layers 7 through 4 deal with end to end communications between the message source and the message destination, while layers 3 through 1 deal with network access."
The OSI model consists of the Physical, Data Link, Network, Transport, Session, Presentation and Application layers.
On the other hand, TCP/IP (the protocol of the Internet) uses four layers to describe the mechanics of networking: the network interface layer, Internet layer, transport layer and application layer.