Home / Companies / Fly.io / Blog / Post Details
Content Deep Dive

How CDNs Generate Certificates

Blog post from Fly.io

Post Details
Company
Date Published
Author
Thomas Ptacek
Word Count
2,241
Company Posts That Month
3
Language
English
Hacker News Points
127
Post removed?
No
Summary

Fly is a content delivery network for Docker containers that uses Firecracker VMs and a global WireGuard mesh. To generate certificates, it utilizes LetsEncrypt's ACME protocol which involves domain-validated certificates based on proof of ownership. The ACME challenges include tls-http-01, tls-dns-01, and tls-sni-01, with the latter being deprecated due to security concerns related to subdomain takeover. Fly mitigates this issue by not reusing IP addresses for applications. The new ACME challenge is tls-alpn-01, which uses ALPN (Application Layer Protocol Negotiation) and is more explicit than the SNI challenge.

Trends Found in this Post
Trend Post Mentions Total Month Mentions Posts Companies MoM
Kubernetes 1 774 105 42 +1%
Use This Data

Use this post, company, and trend context to find content marketing opportunities, perform competitive analysis, or address product feature gaps via the Plushcap MCP server or the Plushcap API.