OSI Model and Network Basics: How Data Travels Across the Internet
Summary: The Complete Journey Your PC (192.168.1.10) │ │ Create HTTP request │ Encode UTF-8 → Compress → Encrypt (TLS) ▼ ┌─────────────────────────────────────────┐ │ Ethernet: Dest=Router MAC │ │ IP: Dest=142.250.190.14 (Google) │ │ TCP: Dest Port=443 │ │ TLS: Encrypted HTTP data │ └─────────────────────────────────────────┘ │ ▼ Your Router (NAT: private → public IP) │ ▼ ISP Routers (forward based on IP) │ ▼ Google Edge Router (forward to internal) │ ▼ Google Load Balancer (NAT: public → private server IP) │ ▼ Google Server (10.0.0.20) │ │ Decrypt → Decompress → Decode │ Process HTTP request ▼ Response travels back the same way What is the OSI Model? A theoretical 7-layer model that describes how data moves from an application to physical transmission. Created in 1984 to standardize network communication. ...