TCP/IP and OSI are the two most widely used networking models for communication. There are some similarities and dissimilarities between them. One of the major difference is that OSI is a conceptual model which is not practically used for communication, whereas, TCP/IP is used for establishing a connection and communicating through the network.
Other differences are discussed below.
Content: TCP/IP Vs OSI Model
|Basis for Comparison||TCP/IP Model||OSI Model|
|Expands To||TCP/IP- Transmission Control Protocol/ Internet Protocol||OSI- Open system Interconnect|
|Meaning||It is a client server model used for transmission of data over the internet.||It is a theoretical model which is used for computing system.|
|No. Of Layers||4 Layers||7 Layers|
|Developed by||Department of Defense (DoD)||ISO (International Standard Organization)|
|Usage||Mostly used||Never used|
The TCP/IP Model was developed before OSI Model, and hence, the layers differ. Concerning the diagram, it is clearly seen that TCP/IP Model has four layers namely, Network Interface, Internet, Transport and Application Layer. Application Layer of TCP/IP is a combination of Session, Presentation and Application Layer of the OSI Model.
Definition of TCP/IP MODEL
TCP (Transmission Control Protocol) /IP (Internet Protocol) was developed by the Department of Defense (DoD) project agency. Unlike OSI Model, it consists of four layers, with each having its protocols. Internet Protocols are the set of rules defined for communication over the network. TCP/IP is considered as the standard protocol model for networking. TCP handles data transmission and IP handles addresses.
The TCP/IP suite is a set of protocols that includes TCP, UDP, ARP, DNS, HTTP, ICMP, etc. It is robust, flexible and mostly used for interconnecting computers over the internet.
The layers, TCP/IP, has are:
- Network Interface Layer,
- Internet Layer,
- Transport Layer,
- Application Layer.
Definition of OSI Model
OSI (Open System Interconnect) model was introduced by ISO (International Standard Organization). It is not a protocol but a model which is based on the concept of layering. It has a vertical set of layers, each having different functions. It follows a bottom-up approach to transfer the data. It is robust and flexible, but not tangible.
The seven layers of the model are:
- Application Layer,
- Presentation Layer,
- Session Layer,
- Transport Layer,
- Network Layer,
- Data Link Layer,
- Physical Layer.
Key Differences between TCP/IP and OSI Model
- TCP/IP is a client-server model, i.e. when the client requests for service it is provided by the server. Whereas, OSI is a conceptual model.
- TCP/IP is a standard protocol used for every network including the Internet, whereas, OSI is not a protocol but a reference model used for understanding and designing the system architecture.
- TCP/IP is a four layered model, whereas, OSI has seven layers.
- TCP/IP follows Vertical approach. On the other hand, OSI Model supports Horizontal approach.
- TCP/IP is Tangible, whereas, OSI is not.
- TCP/IP follows top to bottom approach, whereas, OSI Model follows a bottom-up approach.
Concerning the above article, we can conclude that the TCP/IP Model is reliable over OSI Model, TCP/IP is used for end to end connection so as to transmit the data over the internet. TCP/IP is robust, flexible, tangible and also suggests how data should be sent over the web. The transport layer of TCP/IP Model checks whether the data has arrived in order, it has an error or not, lost packets are sent or not, acknowledgement is received or not, etc.