What are the main differences between OSI and TCP/ IP reference models? Explain briefly.

We will be considering only on the key differences among the two references models. Three ideas are central to OSI model as: interfaces, services and protocols. OSI model creates the clear distinction between these three concepts. The TCP/IP model did not originally obviously distinguish among services, protocol and interface. For illustration the only real services offered through the Internet layer are SEND IP packet and RECEIVE IP packet.

The reference model of OSI was devised before the protocols were invented. Its ordering implies that model was not biased towards one exact set of protocols that made this quite general.

Along with TCP/IP reverse was true: the protocol came initially, and the model was really just a description of the existing protocols. Therefore problem was model did not fit for any other protocol stack.

The other difference is in the area of connection versus connectionless oriented communication. The OSI model assists both connectionless and connection oriented communication into network layer, although only connection oriented into the transport layer. In the TCP/ IP model has only connectionless mode into network layer but assists both the mode in transport layer.