[dns-operations] resolvers considered harmful

Robert Edmonds edmonds at mycre.ws
Wed Oct 22 20:32:28 UTC 2014

Paul Vixie wrote:
> [...] we can move the stubs to an HTTPS transport if we can agree on a
> RESTful query API and either JSON or XML schema for responses, but it
> is not in our power to make UDP, especially fragmented UDP as in EDNS,
> work in the last mile. [...]

Why does moving to a new transport require re-designing the encoding

Register a new IANA media type, e.g., "application/dnsmessage", defined
as a binary DNS message, encoded per RFC 1035 §4.1.

See RFC 4027, 2540 for a related precedent, the extant "application/dns"
media type:


The HTTP client POSTs to a static entry point for this hypothetical
DNS-over-HTTP proxy, setting request headers:

    Accept: application/dnsmessage
    Content-Type: application/dnsmessage

and attaching the RFC 1035 §4.1 encoded DNS query message as the request

The HTTP server responds with status code 200 and sends the RFC 1035
§4.1 encoded DNS response message as the response body.

Robert Edmonds

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