Network Basics: TCP/IP and OSI Network Model Comparisons
Internet Protocol (IP) version 4 (IPv4) is the current standard IP protocol used with TCP/IP — Transmission Control Protocol/Internet Protocol — which is the protocol for Internet addressing. Like the Open System Interconnection (OSI) model, TCP/IP has its own model.
The OSI model and the TCP/IP models were both created independently. The TCP/IP network model represents reality in the world, whereas the OSI mode represents an ideal. With that said, the TCP/IP network model matches the standard layered network model as it should.
The following figure shows the relationship between the OSI model and the TCP/IP model.
The TCP/IP network model has four basic layers:
Network interface (layer 1): Deals with all physical components of network connectivity between the network and the IP protocol
Internet (layer 2): Contains all functionality that manages the movement of data between two network devices over a routed network
Host-to-host (layer 3): Manages the flow of traffic between two hosts or devices, ensuring that data arrives at the application on the host for which it is targeted
Application (layer 4): Acts as final endpoints at either end of a communication session between two network hosts