Re: problem statement [was Re: New Version Notification for draft-hinden-ipv4flag-00.txt]

[Brian E Carpenter <[e-mail]>]

On 20/11/2017 03:25, Nick Hilliard wrote:
> Lorenzo Colitti wrote:
>> Let's not forget about battery life. According to the numbers in RFC
>> 7772, on a phone even just sending DHCPv4 packets every 2 minutes could
>> reduce battery life by ~8% compared to a completely idle device.
> 
> is there any guarantee in this situation that any other apps would not
> be chattering in the background over ipv6 anyway?  From what I've seen
> on tcpdump, mobile phones tend to be extraordinarily noisy, and a dhcpv4
> packet every two minutes would, in any situation where I've examined
> mobile phone traffic from normal handsets, be nothing more than
> background noise.
> 
> Also, the whole internet isn't a mobile phone network, and what might be
> relevant or appropriate on a cell network might not be in any way
> relevant to another type of network.  

My phone has been instructed to prefer WiFi when there is a choice.

> Without meaning to state the
> obvious, it would be important to take this into account when framing
> any problem statement.
> 
> One relatively straightforward way of dealing with extraneous dhcpv4
> packets would be to create a new dhcpv4 reply option hinting to the
> requester to cease DHCPv4 requests on the interface in question, or to
> slow down the request rate from one every two minutes to one every X
> minutes where X is network defined.

The hypothesis of this draft is that there is no IPv4 support, hence
nobody to send a DHCP(v4) reply.

otoh, unable to resist solutionism even in this thread, a minor update
to RFC2131 would allow battery-powered devices to slow down the
DHCPDISCOVER rate as much as they want to.

    Brian