Guides

Caching is one of the simplest ways to improve delivery. A cache saves a copy of a response so it can be served without a round trip to the origin. The core control surface is the Cache-Control header and the time-to-live (TTL). This guide explains how freshness and validation work, which directives do what, and how to choose sane defaults that fit real sites and APIs. Freshness vs validation A cache serves a response when it is fresh. Freshness comes from an explicit lifetime such as max-age or from an older Expires date. After freshness ends, a cache either revalidates or fetches again. ...

Use this framework to shortlist providers: Traffic profile: static assets, APIs, video, images, downloads. Regions/ISPs: where latency and throughput matter to you. Features: WAF, image optimization, video delivery, edge compute, logs. Operational fit: purge SLAs, staging, Terraform/API maturity. Pricing: egress, request costs, commit levels, overage. Support: 24/7 channels, SE coverage, status transparency. Run a short A/B trial in two regions with real traffic before signing.

Why the choice matters A content delivery network (CDN) sits between your origin and end users. It handles caching, routing, and often security. The right provider improves performance and reliability, while the wrong fit can raise costs or limit flexibility. The choice depends on workload, geography, and operational model. Coverage and performance Global reach is uneven. A CDN strong in North America may be weaker in Africa or Southeast Asia. Check where your users are located and compare coverage in those regions. Performance metrics such as latency and throughput matter, but so does stability under peak load. Independent measurement platforms can help validate claims. ...

Why HTTP/3 matters for CDNs HTTP/3 is the next major version of the web’s application protocol. It runs over QUIC, which uses UDP instead of TCP. For CDNs, this change alters how connections are established, how traffic is routed, and how performance is measured. While the protocol foundations are handled elsewhere, CDN users need to understand what changes in day-to-day operations. Latency and connection setup QUIC integrates TLS into its transport layer. This means the handshake takes fewer round trips than TCP with TLS. In practice, first-time connections complete faster, and resumed connections can achieve near-zero delay. For CDNs, this reduces latency on long-haul paths and improves page load times. ...

What purging is Purging is the process of removing cached objects from a CDN. A purge tells the edge nodes that a file should no longer be served from cache. The CDN will then fetch a fresh copy from the origin the next time a client requests it. Purging differs from TTL expiry. TTLs control how long content is considered valid by default. Purges are active interventions to remove content before it would have expired. ...