Subject: Re: [v6ops] draft-ietf-v6ops-reducing-ra-energy-consumption WGLC

From: Lorenzo Colitti <[email-masked]>
Date: Mon, 7 Sep 2015 21:15:07 +0900

On Mon, Aug 31, 2015 at 6:59 AM, David Farmer <[email-masked]> wrote:

> 1. Section "3. Consequences" seems to express disapproval of ignoring RA's
> or IPv6 traffic altogether while devices are asleep.  However, there are no
> recommendations regarding the proper behavior of host implementations in
> this respect within Section 4.  Please clearly recommend RAs not be
> ignored, if that is the intent.  Otherwise, maybe suggest an upper limit on
> the period RA's or IPv6 traffic MAY be ignored by host implementations.
>

There are recommendations on host implementations. Specifically, the draft
says:

   - Mobile devices that intend to maintain IPv6 connectivity while asleep
   MUST NOT ignore RAs while asleep.
   - Mobile devices that do not intend to maintain IPv6 connectivity while
   asleep SHOULD disconnect from the IPv6 network and SHOULD reconnect to the
   network (including performing any DNAv6 procedures [RFC6059], sending
   Router Solicitations and performing Duplicate Address Detection) when
   waking up.

2. Section "4. Recommendations" currently intermixes recommendations for
> router implementations and network operators.  I would like to see three
> sets of recommendations that clearly delineate the recommendations for
> router implementations, host implementations, and network operators
> separately.  This may cause some slight repetition, however I think the
> clarity provided would be very beneficial.
>

There are only 4 recommendations. I split them half way and ended up with:

=========
4.  Recommendations

4.1.  Network recommendations

   1.  Router manufacturers SHOULD allow network administrators to
       configure the routers to respond to Router Solicitations with
       unicast Router Advertisements if:

       *  The Router Solicitation's source address is not the
          unspecified address, and:

       *  The solicitation contains a valid Source Link-Layer Address
          option.

   2.  Administrators of networks that serve large numbers (tens or
       hundreds) of battery-powered devices SHOULD enable this
       behaviour.

   3.  Networks that serve battery-powered devices SHOULD NOT send
       multicast RAs too frequently (e.g., more than one every 5-10
       minutes for current battery-powered devices) unless the
       information in the RA packet has substantially changed.  If there
       is a desire to ensure that hosts pick up configuration changes
       quickly, those networks MAY send frequent Router Advertisements
       for a limited period of time (e.g., not more than one minute)
       immediately after a configuration change.

   No protocol changes are required.  Responding to Router Solicitations
   with unicast Router Advertisements is already allowed by section
   6.2.6 of [RFC4861], and Router Advertisement intervals are already
   configurable by the administrator to a wide range of values.

4.2.  Device recommendations

   1.  Mobile devices that intend to maintain IPv6 connectivity while
       asleep MUST NOT ignore RAs while asleep.

   2.  Mobile devices that do not intend to maintain IPv6 connectivity
       while asleep SHOULD disconnect from the IPv6 network and SHOULD
       reconnect to the network (including performing any DNAv6
       procedures [RFC6059], sending Router Solicitations and performing
       Duplicate Address Detection) when waking up.

=========

I'm not sure if the result is better or worse.

---

From: David Farmer <[email-masked]>
Date: Mon, 7 Sep 2015 11:29:23 -0500

> On Sep 7, 2015, at 07:15, Lorenzo Colitti <[email-masked]> wrote:
> 

The added text uses the term "mobile devices", where as the rest of the document uses the term "battery-powered devices".  I think I prefer the term used in the rest of the document.  Otherwise, the added text resolves two of the issues I brought up.

Thanks.

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