TryHackMe — Networking Concepts | Cyber Security 101 (THM)

OSI Model

The OSI (Open Systems Interconnection) model is a conceptual framework developed by ISO that outlines how communications should occur in a computer network. It consists of seven layers:

1. Physical Layer: Deals with the physical connection between devices, including the transmission medium and binary signal definitions (0s and 1s). Examples include Ethernet cables and WiFi radio bands.
2. Data Link Layer: Represents the protocol for data transfer between nodes on the same network segment. It defines agreements for communication, using protocols like Ethernet (802.3) and WiFi (802.11). MAC addresses are used to identify devices.
3. Network Layer: Manages data transfer between different networks, handling logical addressing and routing. Examples include IP and ICMP protocols.
4. Transport Layer: Enables end-to-end communication between applications on different hosts, supporting flow control, segmentation, and error correction. Key protocols include TCP and UDP.
5. Session Layer: Establishes, maintains, and synchronizes communication sessions between applications. Examples include NFS and RPC.
6. Presentation Layer: Ensures data is in a format understandable by the application layer, handling encoding, compression, and encryption. Examples include ASCII and MIME.
7. Application Layer: Provides network services to end-user applications, using…