Re: [dhcwg] FW: New Version Notification for draft-wing-dhc-dns-reconfigure-01.txt

Isn't this also only half the problem? And doesn't it cause more work for the relay?

What I mean is shouldn't there also be an option for the relay to communicate this for "normal" client traffic? I.e., all Relay-Forws. There might be more values (such as unknown) to be considered -- though I guess not including the option could imply that.

Doesn't this also imply that the relay would have to monitor what the server provided the client to know if it was wrong (and hence trigger a reconfigure). I guess the relay could just do this when things (regarding the client's provisioning) changed.

But what then happens if the client sends requests to the server at a later time? There's no signaling to the server from the relay as to what to send then? If the server sends the wrong information, how would the relay know without monitoring what the server actually delivers to the client (as there may not be a change in the client's connective).

While you could require the server to remember this from a Reconfigure-Request, that seems rather onerous and has issues if this state is lost or becomes stale (i.e., server misses updates from relay).

Also, this mechanism currently requires the clients to support Reconfigure. Otherwise, the relay's request doesn't cause any change at the client.

And, this again is where having this be a normal part of the Relay-Forw would be useful -- at least the server then has the ability to update the client at the next communication.

Note also that server policy to use perhaps shorter Information-Refresh or T1 times when this information isn't available or the relay reports it is 'unknown' could be used to 'correct' the information in the client more quickly once it is determined?

It would also be nice if this was expanded to handle more than DNS -- though exactly what else would use that information isn't completely clear.

Anyway, looks like this work will be discussed in the Sunset4/DHC WG joint session at Berlin (as well as at the DHC wg session).

- Bernie

-----Original Message-----
From: dhcwg-bounces@ietf.org [mailto:dhcwg-bounces@ietf.org] On Behalf Of Prashanth Patil (praspati)
Sent: Friday, June 07, 2013 8:45 AM
To: dhcwg@ietf.org
Cc: Tirumaleswar Reddy (tireddy)
Subject: [dhcwg] FW: New Version Notification for draft-wing-dhc-dns-reconfigure-01.txt

Hi all,
This draft proposes a mechanism to extend DHCPv6 such that a DHCPv6 Relay
Agent can dynamically influence priority of DNS servers provided to a
host, so that a host can use an optimal DNS server for resolution.

Regards,
Prashanth

On 07/06/13 6:05 PM, "internet-drafts@ietf.org" <internet-drafts@ietf.org>
wrote:

>
>A new version of I-D, draft-wing-dhc-dns-reconfigure-01.txt
>has been successfully submitted by Dan Wing and posted to the
>IETF repository.
>
>Filename:	 draft-wing-dhc-dns-reconfigure
>Revision:	 01
>Title:		 DHCPv6 Dynamic DNS Reconfiguration
>Creation date:	 2013-06-07
>Group:		 Individual Submission
>Number of pages: 8
>URL:             
>http://www.ietf.org/internet-drafts/draft-wing-dhc-dns-reconfigure-01.txt
>Status:          
>http://datatracker.ietf.org/doc/draft-wing-dhc-dns-reconfigure
>Htmlized:        
>http://tools.ietf.org/html/draft-wing-dhc-dns-reconfigure-01
>Diff:            
>http://www.ietf.org/rfcdiff?url2=draft-wing-dhc-dns-reconfigure-01
>
>Abstract:
>   Some networks are expected to support IPv4-only, dual-stack, and
>   IPV6-only hosts at the same time.  This makes prioritizing the DNS
>   servers for hosts tricky due to a heterogeneous mix of protocol
>   stacks causing optimal behavior to occur only when the host stack re-
>   initializes.  The networks infrastructure is usually well equipped to
>   be aware of single/dual-stack nature of hosts.  This specification
>   extends DHCPv6 so that a DHCPv6 Relay Agent can dynamically influence
>   the priority of DNS servers provided to the host, so that the host
>   can use an optimal DNS server for resolution.
>
>                  
>        
>
>
>The IETF Secretariat
>

_______________________________________________
dhcwg mailing list
dhcwg@ietf.org
https://www.ietf.org/mailman/listinfo/dhcwg