TheFLDTECtraining describes theTCP/IP encapsulationas a step-by-step process where data is passed down through the layers of the TCP/IP model:

Application Layer: User data is created (email, file, request) and the application layeradds the application header, creating a data payload.

Transport Layer: The data is segmented. Each segment receives a transport-layer header (TCP/UDP), enabling proper sequencing and error handling at the destination.

Internet Layer: Segments are encapsulated intopackets(IP datagrams), with an IPheader added to facilitate routing between networks.

Link Layer: Finally, packets are framed with Layer 2 headers and trailers (including theFrame Check Sequencefor error detection), creating aframeready to be transmitted on the physical medium.

This layered encapsulation ensuresinteroperabilityandtroubleshooting clarity, which is why it is emphasized inFLDTEC’s IOS Software Basics module.