Re: 6MAN WG Adoption Call: draft-nordmark-6man-rs-refresh-01

[Erik Nordmark <[e-mail]>]

On 4/20/15 6:54 AM, Lorenzo Colitti wrote:
> But then the "timely and scalable reconfiguration capabilities" cannot 
> be maintained. The network can't tell that host about any new 
> information, because that host won't receive it. The host will only 
> receive it when it wakes up next.
The host will take no action on any state until it wakes up. "timely" 
implies that hosts do not take any actions on stale state, and with RS 
refresh they would not. Hence it is very "timely".

Note that without RS refresh hosts can take action on stale state if the 
packet loss experienced by the RAs is such that they miss e.g., the RAs 
that set the preferred lifetime for a prefix to zero, or set the default 
router lifetime to zero. Thus RFC 4861 operates in a probabilistic mode 
- which made sense when all networks were wires and one could assume the 
packet loss were independent events. Walking out of range of a radio 
does not result in independent events.

Thus using RS refresh makes the "timely" work better than in RFC 4861.

> It depends how frequent the RAs are. In general purpose networks, they 
> might be more frequent. Also, any node joining may cause a solicited 
> multicast RA. Depending on the application, "after 10 minutes" may be 
> a lot better than "never".
For the network deployments where frequency of RAs is a concern, the 
desire seems to be to increase the time.
If you read e.g. section 5.1 in 
draft-yourtchenko-colitti-nd-reduce-multicast you'll see that.
Those are also the networks where resilient-RS makes sense.

>
> What about points #2 and #3?
I think this email thread should about WG adoption and not WG last call 
or even about WG discussion.
Are you arguing that all your points in the draft need to be addressed 
to your satisfaction before it can even become a WG draft?
That isn't how an IETF working group is supposed to operate.


FWIW your #2 was a statement of fact, but not clear how it is relevant 
to the discussion. Seems to be related to your assumption that any 
multicast RA makes this null and void, which is incorrect.
#3 was AFAICT a restatement of your conclusion based on some unstated 
assumptions. I already tried to guess at that unstated assumption in my 
first respond and I responded based on that. Was my guess wrong? Did I 
you make some other unstated assumptions?

Regards,
    Erik