Data Encapsulation

Transport Layer (L4): - Segments

• Data is segmented into smaller units of "segments"
• Adds a segment header, including [port numbers and sequence] numbers.

Network Layer (L3): - Packet

• Segments are encapsulated into  "packets"
• Adds a packet header, including [source and destination IPv4 (L3 Address)] addresses.

Data / Link Layer (L2): - Frame

• Packets are encapsulated into "frames"
• Adds a frame header and trailer, including [ MAC & Frame (L2) and check-sum]

OSI Protocols