Question

Discuss about OSI model with its layers.

Answer 1

• Open System Interconnection (OSI) model was found in the year 1934, a general framework that enables network protocols along with software and systems to be developed based on a general set of guidelines.
• It describes the standards for inter-computer communication.

OSI Layers:

• Physical Layer:

1. It is the 1st layer.
2. It defines the electrical and physical specifications for devices.

• Data Link Layer:

1. It is the 2nd layer.
2. It guarantees that the data transmitted are free of errors.
3. This layer has simple protocols like “802.3 for Ethernet” and “802.11 for Wi-Fi”.

• Network Layer:

1. It is the 3rd layer.
2. It is used to determine the path of the data packets.
3. At this layer, routing of data packets is found using IP Addressing.

• Transport Layer:

1. It is the 4th layer.
2. It guarantees the transportation/sending of data is successful.
3. It includes the error-checking operation.

• Session Layer:

1. It is the 5th layer
2. It is used to identify the established system session between different network entities.
3. It controls dialogues between computers.
4. For instance, while accessing a system remotely, the session is created between your computer and the remote system.

• Presentation Layer:

1. It is the 6th layer.
2. It does the translation of data to the next layer (Prepare the data to the Application Layer). Encryption and decryption protocols occur in this layer such as Secure Socket Layer (SSL).

• Application Layer:

1. It is the 7th layer.
2. It acts as the user interface platform comprising software within the system.