Author: Chirag

Link-state routing inside an organization. Areas, LSAs, the Shortest Path First algorithm, and why OSPF dominates enterprise networks.

The protocol every ISP runs. Autonomous Systems, peering, route advertisements, and why a typo in a BGP config can take down half the internet.

When to hand-write routes vs let protocols figure it out. Tradeoffs, use cases, and why most networks use both.

Routing tables, hops, default gateway. The basic logic of how a packet finds its way from your laptop to a server across the internet.

Two ways to push real-time data from server to client. WebSockets are bidirectional. SSE is one-way and simpler. When to use which.

Resources, verbs, status codes, idempotency. The conventions almost every modern HTTP API follows.

Why each version exists, what changed, and why HTTP/3 abandoned TCP entirely. The performance evolution of the web.

How encryption + certificates make HTTPS work. The TLS handshake step by step, why it matters, and what changed in TLS 1.3.

The protocol that runs the web. Methods, headers, status codes, body — everything happens through these four pieces.

How DNS responses get cryptographically verified. Chain of trust from root to your domain. RRSIG, DS, DNSKEY records.