>Using ESI? VCL? Signed URLs or auth? Any other custom functionality? Are you depending on your provider's bot management features which are "CONTACT FOR PRICE" with other providers?
replyI have no idea what two of those acronyms mean. None of this is part of what a CDN offers.
Yes if you use DDoS protection, or cloudfare’s ZeroTrust or embrace $X proprietary features then what I said no longer applies.
I strictly said DNS and CDN.
ESI = Edge Side Includes think Server Side Includes on a CDN technology as supported by Akamai and used by sites like Ikea to deliver a fast maintainable experience
replyVCL = Varnish Configuration Language i.e. how you configure your Fastly services
If you're just using a CDN as a proxy then there's no lock in but plenty of sites are using CDNs for much more than that