Re: [DNSOP] KSK rollover

["George Barwood" <[e-mail]>]

----- Original Message ----- 
From: "Patrik Wallstrom" <[e-mail]>
To: "George Barwood" <[e-mail]>
Cc: <[e-mail]>
Sent: Thursday, May 13, 2010 9:06 AM
Subject: Re: [DNSOP] KSK rollover



>On May 13, 2010, at 9:56 AM, George Barwood wrote:

>> I have been thinking about KSK rollover in my DNSSEC implementation, and it seems
> that there is currently no  specification for KSK rollover within the DNSSEC protocol.
>> 
>> There is this expired requirements draft
>> 
>> http://tools.ietf.org/wg/dnsop/draft-ietf-dnsop-key-rollover-requirements/
>> 
>> but that's all I found.
>> 
>> Have I missed something? It seems to me that this is a rather vital component if
>> DNSSEC is to be widely deployed.
>> 
>> Are there any plans to revive and/or implement these requirements?

> You probably want to read the Key Timing Considerations draft:
> http://tools.ietf.org/html/draft-morris-dnsop-dnssec-key-timing-02

That is certainly relevant to rollover, but it doesn't specify any means by which
the new DS records can be placed in the parent zone.

http://tools.ietf.org/html/rfc5011 "Automated Updates of DNS Security (DNSSEC) Trust Anchors"

has some relevance, but doesn't provide for parent notification, or for publishing
a DS record *before* the key is published in the zone, which is I think desirable.

The mechanism that occurs to me is to have a new RRtype, say "CDS", with identical
format to the DS record, but placed in the child zone ( and signed by the child zone).
The parent, at regular intervals, or on receiving a notification from the child, would
retrieve the contents of the CDS RRset, and use it as the new DS RRset ( of course
after validating it using the old DS RRset ).

There probably needs to be consideration of how the system can recover after
a KSK is compromised, maybe there should be some minimum time interval
before a new DS record is fully trusted. I have not thought that through.

Well, that's just my immediate thoughts, there may be a better way.

I'm somewhat puzzled that thre is no specification, and apparently no activity on this.

KSK rollover is probably a fairly rare event (maybe once every few years), so possibly
the feeling is that manual procedures will be sufficient. I think a standardized, automated
in-protocol mechanism would be advisable though. Maybe I'm wrong.

Best regards,
George