What it is
A worldwide network of servers that serves site images and files from the point nearest the visitor. Needed when visitors are spread across countries or traffic is high; a small site usually does fine with one server.
How we use it
We connect one when needed for international sites; for Russian sites a server in Russia and light pages matter more.
Where it helps a business
- Visitors are in different countries, and the page must open quickly for all of them.
- Traffic is heavy, with many images and videos, and one server cannot cope.
How we use it
We add a CDN where needed for international sites. For sites aimed at Russia a local server and light pages matter more, and sometimes the opposite of a CDN is right: no external loads at all.
- Not a single external address. The museum complex website demo has to open under any access restrictions: fonts, images, video and the map snapshot live on our own server, and a CSP policy forbids the browser any external address.
- Self-hosted fonts. Valery Afanasiev's business card and the ยซะัั
ะฐะฝะธะต ะะพะฒะพะปะถััยป showcase never call Google Fonts: the font files sit next to the site.
- Long caching. On the business card, styles, scripts and fonts with a version in the URL are cached for a year, while the page itself is always revalidated with the server.
Common problems
- The external service is unavailable. If a font or script loads from someone else's server and that server is blocked or slow, the page breaks.
- A third party sees your visitors. Every external load is a request to someone else.
When you do not need it
A small site for an audience in one country is usually fine with one server in that country and light pages.