Networking

What is AWS Console API Call Architecture? When you use the AWS Management Console in your browser, it makes API calls to AWS services. Understanding how these calls work is important for debugging, blocking specific services, or understanding the security model. Two Types of API Calls 1. Direct Browser → AWS Service API Example: SSM (Systems Manager) API call Browser JavaScript ↓ https://ssm.us-east-1.amazonaws.com/ ↓ AWS Service responds directly Characteristics: Browser makes HTTPS request directly to service endpoint Uses AWS SigV4 authentication (signed with temporary credentials) Subject to CORS (Cross-Origin Resource Sharing) rules Can be blocked via /etc/hosts Shows in DevTools Network tab with service endpoint URL Example from Session Manager: ...

What is Corporate Proxy with SSL Inspection? Corporate proxies intercept HTTPS traffic to inspect content for security and compliance. This is called SSL Inspection or MITM (Man-In-The-Middle). Complete Flow: curl Through Proxy Command: curl -v -x http://proxy.company.com:8080 https://api.example.com/data Step-by-Step Flow: 1. DNS Resolution curl resolves proxy hostname ↓ DNS: proxy.company.com → 192.168.1.100 2. TCP Connection to Proxy curl → proxy:8080 ↓ TCP handshake: SYN, SYN-ACK, ACK ↓ Connection established 3. CONNECT Request (HTTP Tunnel) curl sends: → CONNECT api.example.com:443 HTTP/1.1 → Host: api.example.com → User-Agent: curl/8.0.0 → Proxy-Connection: Keep-Alive Proxy responds: ← HTTP/1.1 200 Connection established Key point: CONNECT doesn’t create new TCP connection - it repurposes existing connection as tunnel. ...

What is HAR File? HAR (HTTP Archive) is a JSON format for recording browser HTTP transactions. Created by exporting from Browser DevTools Network tab. How to Create HAR File Chrome/Edge: 1. F12 → Network tab 2. Reload page or perform action 3. Right-click any request 4. "Save all as HAR with content" Firefox: 1. F12 → Network tab 2. Click gear icon → "Save All As HAR" HAR File Structure Overview { "log": { "version": "1.2", "creator": { ... }, "browser": { ... }, "pages": [ ... ], "entries": [ ... ] } } Complete HAR Structure Root Object { "log": { "version": "1.2", "creator": { "name": "WebInspector", "version": "537.36", "comment": "" }, "browser": { "name": "Chrome", "version": "142.0.0.0", "comment": "" }, "pages": [ { "startedDateTime": "2025-11-28T10:30:45.123Z", "id": "page_1", "title": "Example Page", "pageTimings": { "onContentLoad": 1234.5, "onLoad": 2345.6 } } ], "entries": [ { "pageref": "page_1", "startedDateTime": "2025-11-28T10:30:45.123Z", "time": 308.5, "request": { ... }, "response": { ... }, "cache": { ... }, "timings": { ... }, "serverIPAddress": "192.168.1.100", "connection": "443", "_initiator": { ... }, "_priority": "High", "_resourceType": "fetch" } ] } } log Object Top-level container for all HAR data. ...