The OSI and TCP/IP stands for Open Systems Interconnection and Transmission Control Protocol/Internet Protocol respectively. The main difference between OSI and TCP/IP is that OSI model is a reference model while TCP/IP is an implementation of OSI model.
OSI is a conceptual model that characterizes and standardizes the communication functions of a computing or telecommunication system irrespective of their underlying structure and technology being used. The goal of OSI model is the interoperability of diverse communication systems with standard protocols. It partitions a communication system in abstraction layers. The original version of OSI model defined seven layers. A layer serves the layer above it and is served by the layer below it. For example, a layer that provides the error-free communication across the network provides the path needed by the application above it, while it calls the next layer to send and receive packets that comprise the contents of that path. Two instances at the same layer are visualized as connected by a horizontal connection in that layer.
TCP/IP is a core protocol of the Internet Protocol Suite (IPS). It is the basic communication language or protocol of the internet. It can be used as a communications protocol in a private network either an intranet or an extranet. TCP/IP is a two layer program. The upper or higher layer TCP, manages the assembling of a message or file into smaller packets that are transmitted over the internet and received by a TCP layer that reassembles the packets into the original message. The lower layer IP, handles the address part of each packet to get the right destination. Each gateway computer on the network checks this address to see where to forward the message. Even though some packets from the same message are routed differently than others, they will be reassembled at the destination.
- The OSI model is a “generic, protocol-independent standard”. The TCP/IP are regarded as the standard around which the internet has developed.
- TCP/IP is a simple model because of fewer layers (four) as compare to OSI that defined seven layers in original version.
- TCP/IP is more reliable model as compare to OSI model because the internet was developed around it.
- The OSI model is bottom to up process of network connection whereas the TCP/IP is the top to bottom process structure for internet purpose.
- The TCP/IP combines the OSI data link and physical into network access layer.
- OSI model is a reference model while TCP/IP is an implementation of OSI model.