The DNS already supports NOTIFY, which is a push notification for updates to a zone (this is something set up by the operators of the auth servers, typically fo

The DNS already supports NOTIFY, which is a push notification for updates to a zone (this is something set up by the operators of the auth servers, typically for mirrors/secondaries so that they know when to request a zone transfer); the alternative, polling, requests the SOA RR for a zone and compares serial numbers. Didn't give it a detailed read, but this looks like a more granular proposal, an example given being printer discovery.