What is decapsulation?

What is decapsulation?

• A. Adding a header
• B. Removing the header as data moves to the receiving device
• C. Fragmenting data
• D. Encrypting data

Answer: (B)

Decapsulation is the process that happens at the receiving host where the headers (and trailers) added by each protocol layer as data traveled down the stack are removed. As a packet arrives, the data link layer strips its header and trailer, the network layer removes the IP header, the transport layer removes its header, and the payload is then delivered up to the appropriate application. This stepwise header removal is what allows the original data to be handed off correctly to the destination application. The described action—removing the header as data moves to the receiving device—captures this concept. Adding a header is encapsulation, not decapsulation. Fragmentation splits data into smaller pieces, and encryption protects data; neither describes header removal at the receiving end.

Decapsulation is the process that happens at the receiving host where the headers (and trailers) added by each protocol layer as data traveled down the stack are removed. As a packet arrives, the data link layer strips its header and trailer, the network layer removes the IP header, the transport layer removes its header, and the payload is then delivered up to the appropriate application. This stepwise header removal is what allows the original data to be handed off correctly to the destination application. The described action—removing the header as data moves to the receiving device—captures this concept.

Adding a header is encapsulation, not decapsulation. Fragmentation splits data into smaller pieces, and encryption protects data; neither describes header removal at the receiving end.