Re: [Gen-art] Gen-ART Last Call review of draft-ietf-dnsop-edns-tcp-keepalive-04

[Tim Wicinski <[e-mail]>]

Brian

Thanks for the review - comments in line.

On 11/22/15 8:58 PM, Brian E Carpenter wrote:
> I am the assigned Gen-ART reviewer for this draft. The General Area
> Review Team (Gen-ART) reviews all IETF documents being processed
> by the IESG for the IETF Chair.  Please treat these comments just
> like any other last call comments.
>
> For more information, please see the FAQ at
> <http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>.
>
> Document: draft-ietf-dnsop-edns-tcp-keepalive-04.txt
> Reviewer: Brian Carpenter
> Review Date: 2015-11-23
> IETF LC End Date: 2015-11-30
> IESG Telechat date:
>
> Summary: Ready with issues
> --------
>
> Comment: These are only standards-language issues, nothing fundamental.
> --------
>
> Major Issues:
> -------------
>
> Last paragraph of section 3.2.2.  Receiving Responses:
>
>     A DNS client that sent a query containing the edns-keepalive-option
>     but receives a response that does not contain the edns-keepalive-
>     option should assume the server does not support keepalive and behave
>     following the guidance in [DRAFT-5966bis].  This holds true even if a
>     previous edns-keepalive-option exchange occurred on the existing TCP
>     connection.
>
> Firstly, shouldn't that "should" be a SHOULD?

Yes, that should be a SHOULD.  Good catch

>
> More important, [DRAFT-5966bis] really looks like a normative reference to me.
> I couldn't code this without reading that reference. It's already entering
> Last Call so hopefully this won't waste much time.

That's interesting. I think we decided to make it informative is that 
its covering new discussions.

>
> Section 3.6.  Anycast Considerations:
>
>     ...
>     Changes in network topology between clients and anycast servers may
>     cause disruption to TCP sessions making use of edns-tcp-keepalive
>     more often than with TCP sessions that omit it, since the TCP
>     sessions are expected to be longer-lived.  Anycast servers MAY make
>     use of TCP multipath [RFC6824] to anchor the server side of the TCP
>     connection to an unambiguously-unicast address in order to avoid
>     disruption due to topology changes.
>
> IMHO, [RFC6824] is another normative reference; and it's a downref since
> it's an Experimental RFC. I think you could avoid this by weakening
> the last sentence a bit:
>
>     It might be possible for anycast servers to avoid disruption due to
>     topology changes by making use of TCP multipath [RFC6824] to anchor
>     the server side of the TCP connection to an unambiguously unicast address.
>

That's a useful edit. I'll circle back to the authors on this.

thanks again

tim