🌐 Networking Knowledge Base
A structured guide covering everything you need to know about computer networking — from low-level protocols to distributed API design — with Java/Spring examples and interview questions throughout.
Topics Covered
| # | Topic | Description |
|---|---|---|
| 1 | OSI & TCP/IP Models | Layered models, encapsulation, ARP, ICMP, troubleshooting |
| 2 | TCP, UDP & Transport Layer | Handshake, flow control, congestion, UDP use cases |
| 3 | HTTP & HTTPS | HTTP/1.1–3, TLS handshake, headers, caching, CORS |
| 4 | QUIC & Modern Transport | QUIC internals, 0-RTT, HOL blocking, HTTP/3, BBR |
| 5 | DNS | Resolution process, record types, TTL, DNSSEC, DoH |
| 6 | CDN & Load Balancing | CDN architecture, LB algorithms, health checks, Anycast |
| 7 | Network Security | TLS, firewalls, DDoS, Zero Trust, mTLS, cert management |
| 8 | API Authentication & Authorization | OAuth 2.0, JWT, OIDC, client credentials, mTLS |
| 9 | Socket Programming & I/O Models | Sockets, blocking/NIO, epoll, Netty, virtual threads |
| 10 | REST & gRPC API Design | REST, gRPC/protobuf, GraphQL, versioning, OpenAPI |
| 11 | WebSockets & Real-Time | WS protocol, SSE, long polling, Spring WebSocket |
| 12 | Proxies, NAT & Firewalls | Forward/reverse proxy, NAT, nginx, Spring behind proxy |
| 13 | IP Addressing & Routing | IPv4/IPv6, CIDR, subnetting, BGP, OSPF, DHCP |
| 14 | Network Performance & Optimization | Latency, throughput, TCP tuning, connection pooling |
| 15 | Service Mesh & Microservices Networking | Istio, Envoy, circuit breaker, service discovery, K8s |
| 16 | Network Troubleshooting Tools | tcpdump, Wireshark, curl, openssl, dig, nmap, ss |
| 17 | Application Protocols Reference | SMTP, FTP, SSH, SNMP, NTP, MQTT, WebRTC |
| 18 | Interview Questions — Master List | Top questions across all topics, interview-ready answers |
Java / Spring Focus
Java NIO, Netty, Spring WebFlux, Spring WebSocket, gRPC-Java, WebClient, Spring Security OAuth2, and Resilience4j examples are included throughout.