Data Encapsulation in the OSI Model

The video explains data encapsulation and decapsulation in the OSI model. It describes how data is processed and transformed as it moves through different network layers, from the application layer down to the physical layer, and then back up in the reverse process. Key concepts include headers, trailers, and protocol data units (PDUs) at each layer, with a focus on how data is packaged and unpackaged for transmission.

What is the primary purpose of data encapsulation in the OSI model?

• To compress data for storage

• To add headers and trailers for data transmission

• To encrypt data for security

• To convert data into audio signals

At which layer does data get encoded or compressed to a standard format?

• Session Layer

• Presentation Layer

• Transport Layer

• Application Layer

What is the term used for the data unit at the transport layer when TCP is used?

• Packet

• Segment

• Frame

• Datagram

Which layer adds the IP header containing source and destination IP addresses?

• Physical Layer

• Transport Layer

• Network Layer

• Data Link Layer

What is the role of the trailer added at the data link layer?

• To encrypt the data

• To mark the end of the frame and check for errors

• To add a session ID

• To compress the data

What happens to the frame at the physical layer?

• It is encrypted

• It is converted into a signal

• It is compressed

• It is discarded

During decapsulation, what is the first step at the physical layer?

• Encrypting the data

• Adding a header

• Compressing the data

• Interpreting bits as a frame

What is checked at the data link layer during decapsulation?

• IP address

• MAC address and errors

• Port number

• Session ID

Which layer examines the segment header during decapsulation?

• Application Layer

• Presentation Layer

• Network Layer

• Transport Layer

What is the final step in the decapsulation process?

• Data is discarded

• Data is restored to its original form

• Data is compressed

• Data is encrypted