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Network+ Exam

OSI Model

October 29, 2025

  • #network+

OSI Model

Open systems interconnetion (OSI) model

OSI Stack

Made up of 7 layers. This is Domain 1 Explain concepts to the OSI model. The 7 layer are useful when troubleshooting a network.

OSI is a refrence model

TCP/IP is the real world network model that we use.

Layer 1 - (Physical)

Layer 2 (Data Link)

Layer 3 (Network)

Layer 4 (Transport)

Layer 5 (Session)

Layer 6 (Presentation)

Layer 7 (Application)

Data changes as it moves down from data, segments, packets, frames, bits.

Encapsulation

Wireshark