OSI Model?

Physical Layer (Layer 1):
This is where the actual physical connection happens, like cables, wireless signals, and network devices (routers, switches).
It converts data into electrical signals or light pulses to send it over physical media.
Example: Ethernet cables, Wi-Fi signals, fiber optic cables.

1. Data Link Layer (Layer 2): This layer ensures that data can move between devices on the same network. It creates frames from the data, adds error checking, and helps avoid issues with collisions. It also uses MAC addresses to ensure devices can communicate. Example: Ethernet, Wi-Fi (MAC addresses).
2. Network Layer (Layer 3): This layer is responsible for routing data across different networks. It uses IP addresses to send data to the correct destination. Think of this layer as the postal system of the internet, figuring out the best route for the data to take. Example: Routers, IP addresses, IPv4/IPv6, OSPF, BGP.
3. Transport Layer (Layer 4): It ensures that data arrives reliably by breaking it into smaller pieces (called segments) and ensuring they’re reassembled correctly at the destination. It also ensures that data is sent in the right order and handles flow control and error correction. Example: TCP (Transmission Control Protocol), UDP (User Datagram Protocol), SSL/TLS.
4. Session Layer (Layer 5): This layer manages the communication session between devices. It ensures that sessions are properly established, maintained, and terminated once data exchange is done. It also ensures data synchronization to avoid errors. Example: Remote Desktop Protocol (RDP), API calls, login sessions.
5. Presentation Layer (Layer 6): The presentation layer is all about data formatting. It converts data into a format that the receiving application can understand. It also encrypts or compresses data for secure and efficient transmission. Example: SSL/TLS encryption, image file formats (JPEG, PNG), data compression.
6. Application Layer (Layer 7): The top layer is where end-user applications interact with the network. It provides network services like web browsing, email, file transfer, and more. This is where users experience the network directly (through their browsers or apps). Example: HTTP/HTTPS (web browsing), SMTP (email), FTP