Hi all,

We just uploaded an absolutely trivial new draft that is intended to close two 
holes that should be easy to close once we have DSYNC published (it is in the 
RFC Editor queue since earlier this spring).

https://datatracker.ietf.org/doc/draft-berra-dnsop-announce-scanner/

What holes may that be?

Hole #1: what is the frequency of the parent scanner?

As I work for a parent (.SE) that actually does both CDS and CSYNC scanning I 
know for a fact that we regularly get emails from children that are confused 
that we have not picked up on the CDS or CSYNC that they just published. We 
explain that the scanner only runs once every 24h and case is closed. 

Hole #2: is there a scanner at all or not?

Up until now there has been no standardized method for finding out (a) if there 
is a parent-side CDS (and/or CSYNC) scanner. Sure, we publish the existence on 
a web page somewhere, but I’m sure that child-side software will not read that. 
I’m also sure that other scanner operators publish existence of their scanners 
in some way differently from how we do it. And also human operators will 
typically not bother to hunt for that information.

However, my assumption (or perhaps, my hope) is that as DSYNC gains use there 
will be an increasing amount of child-side software systems that look for the 
DSYNC RRset to figure out how to announce new CDS and/or CSYNC publications. So 
then we can obviously use that to send signals back directly to the child 
system.

Our proposal is the following:

a) To signal the ABSENCE of a scanner or the FREQUENCY of a scanner that does 
not support generalized notifications the parent should publish a DSYNC record 
with a Target of “.” I.e. the target “.” should be interpreted as “don’t send 
notifications here, we’re just trying to tell you something”.

b) In the ABSENCE of a scanner, set the Port to 0 (zero). I.e.:

example.    DSYNC CDS NOTIFY 0 .

is effectively a statement that says “there is no CDS scanner here, we will not 
se your CDS records, don’t email us to ask whether our scanner is broken, etc…”

c) In the PRESENCE of a scanner, but no support (yet) for generalized 
notifications, set the Port to the intended frequency of the scanner, measured 
in minutes. I.e.:

Example.     DSYNC CSYNC NOTIFY 1440 .

is a statement that “yes, there is a CSYNC scanner, but it only runs once every 
24h and we do not (yet) support generalized notifications, please have some 
patience”.

Consequences:

Parent-side there is zero implementation work. Publishing these records is just 
policy statements.

Child-side there is limited implementation work to deal with this information 
from the parent. If a child-side implementation doesn’t want to deal with this 
information then that’s ok and nothing will break. But, presumably child side 
implementations are not yet set fully in stone, and by checking this data (if 
it is published by the parent) may allow them to set expectations correctly and 
thereby work better.

The draft is only a couple of pages long and we appreciate all and any comments.

Regards,
Johan

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

_______________________________________________
DNSOP mailing list -- [email protected]
To unsubscribe send an email to [email protected]

Reply via email to