Inter-domain DNS Request Routing
Provider A has site cdn.blah.com to distribute
- Origin is: www.blah.com
- Assume A is authoritative CDN
If provider B wants to distribute, it must supply a CNAME for redirect of www.blah.com
Provider A request-routing system will redirect requests to B according to its policy
- Provider B will receive request (through CNAME) and pick an appropriate surrogate in its network
Key points:
- Must agree to distribute
- Must supply information back to upstream