Starting in Varnish 6.0, we have a new and exciting solution that is a game changer when it comes to content acceleration. The solution is Varnish E-Commerce Accelerator and it allows Varnish to cache previously uncacheable Magento content.
There once was a time that building your own CDN would have been unthinkable - complicated, expensive and not worth the hassle, considering that there were a number of well-known commercial CDN providers available who could make it easy to distribute content reliably across the geographies a company wanted to reach. CDN vendors offer the full package: hardware, software, network and so on, meaning that, for a long time, for most companies, convenience trumped other considerations.
Lately the content delivery industry looks more like a meteorological website for alpinists than anything else.