Understand the edge.
A CDN adds a distributed delivery layer between your visitors and the source of your content. Understanding that request path helps you choose what to cache, protect information that belongs to one visitor, and compare delivery services against the requirements of your actual website.
Start with the source and the response
The origin supplies the authoritative content. It can be a web server, object storage, or an application that generates a response on demand. An edge server receives the visitor's request and checks whether a suitable stored response can be reused. A cache hit can avoid another origin fetch; a miss or required validation involves an upstream request.
These roles can be offered by separate providers or included in one hosting platform. Identify what your host already supplies before adding another delivery layer. Our CDN and hosting comparison explains the responsibilities in common website architectures.
Global delivery depends on the request
Network proximity can reduce delivery delay, but a map of server locations does not predict every visitor's experience. Routing, connectivity, cache state, file size, and origin response time all matter. A location may need to fetch content before it can reuse a copy, so repeated requests and first requests can behave differently.
Classify your traffic before making changes. Public images and versioned stylesheets are often straightforward candidates. Personalized account pages require different handling. Public HTML may be reusable when its variation and freshness requirements are understood. The important question is whether two requests can safely receive the same response.
Compare the requirements that matter
- Audience: test from the countries, networks, and device conditions your visitors actually use.
- Content: identify large downloads, public pages, personalized responses, and frequently changing assets.
- Publishing: confirm how updated content replaces or invalidates stored copies.
- Operations: check available logs, configuration controls, support, and a documented recovery process.
- Cost: compare the complete workload, including requests, delivery, origin traffic, and optional features.
Write those requirements down before comparing product descriptions. A small documentation site and a personalized application can have very different priorities even with similar visitor counts. Keep the first implementation narrow, record the baseline, and use the CDN testing checklist to confirm correctness as well as speed. Expand coverage after the initial behavior is understood.