CDN Cost Optimization

CDN egress vs origin egress.

Overview

CDN cost optimization recognises that CDN egress is dramatically cheaper than origin egress and architects content delivery around that economics. CloudFront, Fastly, and Cloudflare egress runs roughly 1/2 to 1/4 of EC2 egress for most regions; pushing more traffic through the CDN (high cache hit rates, origin shield, regional pricing awareness) produces savings that recur with every byte served.

• CDN egress vs origin egress. Per-byte cost differential is significant; CDN egress is cheaper than origin egress in every region.
• Cache hit rate. Per-CDN hit rate drives cost; below 80 percent the CDN is paying origin transit, above 95 percent it is paying for itself.
• Origin shield. Single regional cache between edges and origin; reduces origin load by collapsing duplicate fetches across edge locations.
• Per-region pricing plus quarterly audit. Per-region egress cost varies (cheaper in NA, expensive in Asia); per-quarter audit catches drift in hit rate and shield effectiveness.

The approach

The practical approach is to drive cache hit rate up via cache-key design and TTL tuning, enable origin shield to reduce origin load from edge locations, model per-region pricing into the architecture decision (where to host origins), run quarterly audits against CDN cost dashboards, and document the per-CDN configuration so the rationale is reviewable.

• Hit-rate driven. Per-CDN hit rate as the primary cost lever; tune cache keys and TTLs to maximise it.
• Origin shield. Single regional cache between edges and origin; collapses duplicate fetches across edges.
• Per-region pricing. Per-region egress cost informs origin placement; cheaper regions for origin reduce shield-to-origin transit cost.
• Per-quarter audit plus documented policy. Quarterly CDN cost review against dashboards; per-CDN configuration rationale committed to the infrastructure repo.

Why this compounds

CDN cost discipline compounds across bytes served. Each percentage point of hit-rate improvement reduces ongoing egress cost on every byte; each origin shield deployment reduces origin load durably; the team builds intuition for content-delivery economics that pays off on every new asset class.

• Cost efficiency. Right hit rate matches workload; the bill tracks origin-served bytes rather than CDN-served bytes.
• Latency. Right CDN matches the user; user-facing latency drops at edge.
• Operational fit. Right architecture matches workload; CDN absorbs cacheable traffic, origin handles dynamic.
• Institutional knowledge. Each tuning teaches CDN patterns; the team learns where caching pays off and where it does not.

CDN cost discipline is an operational discipline that pays off across years. Nova AI Ops integrates with edge telemetry, surfaces hit-rate patterns, and supports the team’s content delivery discipline.