Hi, I’m DaYul Lee, a backend developer candidate with a business background. Over the past two months, I’ve put together a 5-part series on networking.

As a non-CS major, the hardest part wasn't memorizing concepts, but figuring out "why it was designed this way." I couldn't find resources explaining the exact problems behind OSI, TCP, or HTTP, so I wrote this focusing strictly on the 'why' and the flow. I hope this also bridges the communication gap between devs and non-devs.

Part 1. OSI 7 Layer (A Map to Finding Bottlenecks): Traces "where problems occurred" rather than rote memorization. Part 2. TCP Handshake (The Cost of Connection): Focuses on why this process is essential for real-world reliability. Part 3. Evolution of HTTP (A History of Trade-offs): Looks at the struggles of each version and what they sacrificed to fix them. Part 4. Load Balancer (Dividing Traffic with Information): Explores how different methods choose trade-offs based on how they handle information. Part 5. CDN, WebSocket, Idempotency (Architectures for Real Traffic): Uses real scenarios to show how these tech click together under high load.

Any feedback or different perspectives are always welcome! Here is the link. Hope this helps your studies!

👇 My blog:lukyday

Next up: a Database (DB) series, focusing again on "why this structure is necessary."