JobCannon
All skills

CDN Architecture

Global content delivery for fast, reliable web experiences

⬢ TIER 2Technical
Medium
Salary impact
6 months
Time to learn
Medium
Difficulty
2
Careers
At a glance

CDN Architecture is mastery of global content delivery, edge caching, and origin infrastructure: cache-control headers, cache key strategies, surrogate-key invalidation, origin shielding, edge compute (Workers/Compute@Edge), regional failover, and cost optimization. Career path: Practitioner (static asset CDN, $90-120k) → Intermediate (cache strategies, origin optimization, $120-155k) → Advanced (edge computing, multi-CDN, $155-210k) over 6-9 months. Market tools: Cloudflare (300+ PoPs, Workers), Fastly (edge compute leader), AWS CloudFront (deepest AWS integration), Bunny.net (performance-per-dollar), Akamai (enterprise scale).

What is CDN Architecture

1. Week 1, CDN Fundamentals. Understand PoP (point of presence) networks, latency reduction, caching at edge. Measure latency from multiple geos using WebPageTest. Resource: Cloudflare Learning Center intro, Fastly docs. 2. Week 2, Cache Headers & Configuration. Study Cache-Control (public, max-age, s-maxage), surrogate-key/cache-tags. Configure basic CDN for a static site (HTML + assets). Resource: Cloudflare Cache Rules, Fastly VCL intro.

🔧 TOOLS & ECOSYSTEM
CloudflareFastlyAWS CloudFrontBunny.netAkamaiVercel Edge NetworkCloudflare WorkersFastly Compute@EdgeAWS Lambda@EdgeVarnishNGINX cachingHTTP cache headers

💰 Salary by region

RegionJuniorMidSenior
USA$100k$150k$210k
UK£65k£95k£140k
EU€70k€105k€155k
CANADAC$115kC$165kC$235k

🎯 Careers using CDN Architecture

Devops Engineer
Network Engineer

❓ FAQ

CDN vendor choice in 2026, Cloudflare vs Fastly vs CloudFront vs Bunny?
Cloudflare: best all-around, 300+ PoPs, Workers free tier, DDoS included, $20-200/mo. Fastly: edge compute leader, bare-metal for ultra-low latency, expensive ($0.12/req). AWS CloudFront: deepest integration with S3/Lambda, regional discount, pay-per-GB. Bunny.net: best performance-per-dollar ($0.01/GB), no API rate limits, smaller brand. Pick: AWS-native stacks → CloudFront; startups + DX → Cloudflare; performance obsessive → Fastly; price-sensitive → Bunny.
When should I use edge compute (Workers/Compute@Edge) vs origin?
Edge compute: A/B testing, image resizing, auth, geo-routing, request rewriting, <100ms operations. NO database queries, file I/O, or >10MB payloads. Origin: business logic, DB calls, complex state. Hybrid: edge handles 80% (cache hits + transformations), origin handles the 20% (cache misses + mutations). Cost: Workers $0.50/1M requests; Compute@Edge $0.12/request is pricey.
Cache-Control vs Surrogate-Key vs cache tags, which invalidation strategy?
Cache-Control (public/max-age/s-maxage) is HTTP standard, works everywhere. Surrogate-Key is Fastly/Akamai, allows tag-based instant purge (e.g., purge all posts by author). Cache tags are Cloudflare's version. For content that changes together: use surrogate-key/tags + instant purge. For time-based expiry: Cache-Control s-maxage. Hybrid: s-maxage=86400 (24h default) + surrogate-key=author:123 (purge on update).
Image CDN strategy, separate domain or same CDN?
Separate domain (e.g., cdn.example.com for images, api.example.com for API): cleaner cache isolation, easier resize-on-upload, avoids cookie bloat. Same CDN with path-based routing: simpler ops, one vendor relationship. Modern: Vercel Image Optimization or Cloudflare Image Resizing (on-demand transforms). For high volume: dedicated image CDN (Imgix, Cloudinary) with your CDN in front.
Multi-CDN load balancing, is it worth the complexity?
Yes if: >100k rps, region-specific SLAs, vendor incident risk, negotiating volume discounts. How: GeoDNS (Route53, Dyn) routes to primary/secondary CDNs per region. Or: failover at origin (try Fastly → fallback CloudFront). Overhead: 2-5% extra cost for dual-ingestion, operator complexity. Small-mid companies: stick to one CDN, prioritize cache hit rate.
Image optimization at edge, resize/compress/format in real-time?
YES, if you have 100+ image variants. Tools: Cloudflare Image Resizing ($5/month + compute), Fastly Image Optimizer, AWS Lambda@Edge + Sharp. Workflow: upload original to S3 → querystring params (?w=400&h=300&format=webp) → edge resizes on first request → cache as new variant. Saves 60-80% bandwidth vs serving full-res. Tradeoff: CPU cost + cold-start latency on first resize.
CDN cost optimization, how to not get surprised by the bill?
Set alerts on data transfer. Estimate: 1M users × 2MB per visit × 0.015/GB (CloudFront) = $30/month. Tactics: (1) Enable compression (gzip/brotli, save 60-70%), (2) Immutable filenames + long max-age (cache hits), (3) Lazy-load images (defer non-critical), (4) Origin shielding (Fastly/CloudFront, reduce 404s from cache misses), (5) Smart TTLs (static: 1yr, HTML: 5min, API: 0min). Monitor hit rates; <70% = misconfigured.

Not sure this skill is for you?

Take Career Match — we'll suggest the right tracks.

Find my best-fit skills →

Find your ideal career path

Skill-based matching across 2,521 careers. Free, ~3 minutes.

Take Career Match — free →