shieldCISSP Practice Domain 4 — Communication and Network Security Q72 of 120

Which OSI layer handles end-to-end transport with port numbers?

A CISSP practice question covering Domain 4: Communication and Network Security. Try answering before reading the explanation below.

Show options & answer
A
Layer 2 — Data Link
B
Layer 3 — Network
C
Layer 4 — Transport
✓ Correct answer
D
Layer 7 — Application
Why "Layer 4 — Transport" is the right answer

Layer 4 (Transport) hosts TCP and UDP, which use ports for endpoint identification. Layer 2 uses MAC addresses. Layer 3 uses IP addresses. Layer 7 contains applications and their protocols.

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