> On Aug 17, 2015, at 6:42 AM, Warren Kumari <[email protected]> wrote:
> 
> On Tue, Aug 11, 2015 at 2:00 PM, Joe Touch <[email protected]> wrote:
>> 
>> Hi, Warren,
>> 
>> It might be useful to summarize on this list the rationale for this
>> allocation and the plan for its use.
>> 
>> In particular:
>> 
>>        - why port 53 is not sufficient using STARTTLS
>> 
> 
> - The WG decided that using a new port instead of a STARTTLS or
> octet-matching would better suite our operational goals.
> We had significant discussions on this, and we have concerns about
> things like middle boxes reacting to non-DNS on 53.

Additionally:

- A separate port avoids the 1xRTT incurred by STARTTLS negotiation.

- DNS-over-DTLS can't use STARTTLS (at least not as currently described), 
although
it does claim that it can run on port 53.  That relies on an unaware server
mis-interpreting a DTLS ClientHello message as a DNS message with Opcode=15.  
That,
in turn, takes Opcode 15 off the table for future allocation, etc.


DW

Attachment: smime.p7s
Description: S/MIME cryptographic signature

_______________________________________________
dns-privacy mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/dns-privacy

Reply via email to