Correct Answer - Option 2 : network layer
- OSI stands for Open System Interconnection is a reference model that describes how information from a software application in one computer moves through a physical medium to the software application in another computer.
- OSI consists of seven layers, and each layer performs a particular network function.
- OSI model was developed by the International Organization for Standardization (ISO) in 1984, and it is now considered as an architectural model for inter-computer communications.
There are seven OSI layers. Each layer has different functions. A list of seven layers are given below:
1) Physical Layer:
- The main functionality of the physical layer is to transmit the individual bits from one node to another node.
- It is the lowest layer of the OSI model.
2) Data-Link Layer:
- This layer is responsible for the error-free transfer of data frames.
- It defines the format of the data on the network.
- It provides reliable and efficient communication between two or more devices.
3) Network Layer:
- It is a layer 3 that manages device addressing, tracks the location of devices on the network.
- It determines the best path to move data from source to destination based on the network conditions, the priority of service, and other factors.
- Logical Addressing and Routing are functions of the Network Layer.
4) Transport Layer:
- The Transport layer is a Layer 4 ensures that messages are transmitted in the order in which they are sent and there is no duplication of data.
- The main responsibility of the transport layer is to transfer the data completely.
5) Session Layer:
- The Session layer is used to establish, maintain, and synchronizes the interaction between communicating devices.
6) Presentation Layer:
- It acts as a data translator for a network.
- This layer is a part of the operating system that converts the data from one presentation format to another format.
7) Application Layer:
- An application layer serves as a window for users and application processes to access network service.
- This layer provides network services to the end-users.
HTTP is an application layer protocol designed within the framework of the Internet protocol suite. Its definition presumes an underlying and reliable transport layer protocol, and Transmission Control Protocol (TCP) is commonly used.
Thus, HTTP is an application layer in the OSI Model of Networking.