OSI MODEL
The Open Systems Interconnection (OSI) model is a conceptual 7-layer framework developed by the ISO to standardize networking functions, allowing diverse systems to communicate. It maps the flow of data from software applications down to physical hardware, aiding in troubleshooting, security, and interoperability. A Layer Protocols / Data Data Unit Functions Hardware / Examples A Application HTTP, HTTPS, FTP, TELNET, SMTP, DNS Message Provides services to end-users, interface for apps Browsers (Chrome/Firefox), Email clients, Servers P Presentation JPEG, PNG, GIF, MOV, SSL/TLS Message Data translation, encryption/decryption, compression Handled by software, libraries (e.g., OpenSSL) S Session RPC, NetBIOS, APIs Message Session establishment, managemen...