I want to speed up one of my websites which is enjoyed across the globe. Would one easy way to do this involve using a CDN? I don't fully understand what they are they yet, but I have some vague notion of what they do. I know the name cloudflare and that they have a free plan. This is the limit of my knowledge, any insights, teachings or advice would be well received I also have no idea on what is involved to start one up. thanks.
Benefits: Global DNS presence makes DNS lookups faster for non-local visitors to your servers (useful for Australian visitors for instance - US/UK transfer rates and latency are generally excellent anyway). And also makes DNS more robust, by having more replications. CDN providers are very good at helping prevent DDOS attacks getting out of control. Likewise filtering out other potential attacks. In caching lots of your content locally to all visitors, not only will your site be quicker for browsing, your server load will be massively lower - so you can scale traffic more easily and at a lower hosting cost. Downsides: Potential cache busting issues/overhead when content changes. Extra cost of bandwidth. Although normally highly redundant, a CDN also becomes a potential point of failure. Edit: Worth saying that if you use AMP pages, that goes some way towards achieving the performance benefit on mobile at least.
What Martin said. I know a lot of people put cloudflare's free plan in front of every site they make.
