I’m seeing a “DynDNS2” protocol referenced a lot but I have a hard time locating its specification. AFAICS, RFC 2136 is not versioned on the protocol level so I’m inclined to rule that one out. Somehow I can find numerous implementations of DynDNS2 but the repos I’ve browsed don’t link to a canonical document either.
Example: https://support.google.com/domains/answer/6147083 – that’s Google claiming they support this protocol without further explanation.
Where can I find the official specification of DynDNS2?
Who is in charge of its standardization and development?
The link (now) shows how to do so "manually":
https://username:password@domains.google.com/nic/update?hostname=subdomain.yourdomain.com&myip=1.2.3.4
And gives more specs. You should check the link to the support page again and click the Using the API to update your Dynamic DNS record
Example HTTP query:
POST /nic/update?hostname=subdomain.yourdomain.com&myip=1.2.3.4 HTTP/1.1
Host: domains.google.com
Authorization: Basic base64-encoded-auth-string User-Agent: Chrome/41.0 your_email@yourdomain.com
Also you need to add the User Agent header to make sure your call is not ignored or worse, your client is blocked.
At source forge you can find a list of these dynamic DNS "protocols".