According to the OSI model, at which of the following layers is data encapsulated into a packet?
A.
Layer 2 B.
Layer 3 C.
Layer 4 D.
Layer 5 E.
Layer 6
B.
According to the OSI model, at which of the following layers is data encapsulated into a packet?
A.
Layer 2
B.
Layer 3
C.
Layer 4
D.
Layer 5
E.
Layer 6
B.
According to the OSI (Open Systems Interconnection) model, data is encapsulated at different layers into different protocol data units (PDUs). The layer at which data is encapsulated into a packet is Layer 3, also known as the Network layer.
The Network layer is responsible for logical addressing and routing of data between different networks. When data is sent from a source device to a destination device across multiple networks, it is broken down into smaller packets and each packet is assigned a unique IP address. This process is called encapsulation, where data is wrapped or encapsulated in a packet with a header that includes the IP address of the destination device.
Once the packet is created, it is sent down to the Data Link layer (Layer 2) for further encapsulation into a frame that includes the source and destination MAC addresses. The frame is then transmitted over the physical network.
Layer 4, also known as the Transport layer, is responsible for end-to-end communication and ensures reliable delivery of data between applications. It encapsulates data into segments or datagrams, depending on the protocol being used.
Layers 5 and above deal with application-level protocols and do not directly encapsulate data into packets. Layer 6, also known as the Presentation layer, is responsible for data encryption and decryption, while Layer 7, also known as the Application layer, deals with protocols such as HTTP, SMTP, FTP, and Telnet.
Therefore, the correct answer to the question is B. Layer 3 (Network layer).