Computer Network Models
Here, we are going to know about computer network models. Before that I would like to suggest you to go through the previous post. There are mainly two types of models, e.g. OSI model and TCP/IP model.
OSI Network Models :
The International Organization for Standardization (ISO) developed the OSI model in 1984. We now use it as an architectural paradigm for inter-computer communications. The Open System Interconnection (OSI) is basically a reference model. It describes how data goes from one computer’s software application to another computer’s across a physical medium.
Characteristics of OSI Model :
This model consists of two layers – upper layers and lower layers.
1. Upper Layer – The upper layer of OSI model mostly deals with application-related difficulties. They are exclusively implemented in software. The user interacts with application layer the most. Both the end user and the application layer interact with software applications. An upper layer is the layer that is directly above another.
2. Lower Layer – The lowest layer of OSI model deals with data transmission difficulties. We use both hardware and software to implement the data link and physical layers. The physical layer is the lowest layer in the OSI model. It is surely the closest to the physical media. The physical layer is generally responsible for transferring data to and from the physical medium.
The following is a list of seven levels.
- Physical Layer
- Data-Link Layer
- Network Layer
- Transport Layer
- Session Layer
- Presentation Layer
- Application Layer.
TCP/IP Network Models :
The TCP/IP and OSI models came first and second, respectively.
The TCP/IP and OSI models are not interchangeable.
This model has five layers application layer, transport layer, network layer, data link layer, and physical layer.
Physical standards, network interface, inter-networking, and transport services are the first four levels. They basically correspond to the first four layers of the OSI model. These four layers are represented in the TCP/IP paradigm by a single layer called the application layer.
To sum up, TCP/IP is a hierarchical protocol comprised of interconnected modules, each with its own set of capabilities.