Encapsulation is how layering manifests in data representation.
Layer N data is payload to layer N-1
The way this works is each protocol layer has some headers, followed by its payload, followed by some footers.
Hardware: first bit on right
Software: first bit on left
Encapsulation allows you to layer recursively
<aside> 📖 Example
Virtual Private Network (VPN):
▶ HTTP (web) application payload in
▶ a TCP transport segment in
▶ an IP network packet in
▶ a secured TLS presentation message in
▶ a TCP transport segment in
▶ an IP network packet in
▶ an Ethernet link frame.
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