Understanding the OSI Model with a Real HTTP Request Example
Networking is everywhere — from browsing Google to streaming Netflix — but behind the scenes, a lot is happening to make sure data travels safely and reliably. To explain this, engineers often use the OSI Model (Open Systems Interconnection Model) : a framework that splits network communication into seven layers . In this post, we’ll break down the OSI layers, see what software or hardware handles them, and then walk through a real-life example of an HTTP request to Google . 🔹 The 7 Layers of the OSI Model Physical Layer → Transmits raw bits as electrical signals, radio waves, or light pulses. Devices: Cables, Wi-Fi, NICs, hubs. Data Link Layer → Moves frames between devices on the same network. Uses MAC addresses. Devices: Switches, NIC drivers. Network Layer → Routes packets between different networks. Uses IP addresses. Devices: Routers, firewalls. Transport Layer → Ensures reliable end-to-end delivery. Breaks data into segments. Handled...