Not so long ago and not so far away, the idea of building your own CDN was a complex, remote and expensive proposition, requiring more technical expertise than most companies delivering digital content wanted to commit when there were perfectly reasonable commercial CDN options available.
When using a traditional CDN or caching system, creating user-centric security and access policies can be a complex and performance challenging undertaking. Not only do you have to pull user data from a backend, but you then have to apply the security policies from that data onto the request. VCL is an excellent candidate for the latter problem of applying security policies to requests. This leaves the problem of how you get user data (JSON) into VCL? How do you do that on a user-by-user basis? And how do you do that in a way where you keep backend communication to an absolute minimum, or put another way, serve as much data from cache as possible?
You hear and read a lot these days about “taking back control of your content” … but are you really in control of your content when its delivery is in someone else’s hands? Or when you can’t decide how you want to manage the content and its delivery? Anyone who delivers copious amounts of content, has unconventional needs or wants to create a solution that works to the advantage and convenience of their own requirements will recognize that it’s kind of an adventure finding the right balance.
“Not everybody does it but everybody should…” Okay, quoting George Michael circa 1987 won’t get us anywhere, and the truth is, not everybody should build their own content delivery solution. But you should know that the option is there if you’ve got the need. Some companies do indeed have a need, with clear cases for building a private content delivery solution for themselves.