Re: [Ecrit] AD evaluation: draft-ietf-ecrit-ecall-20

[Alissa Cooper <[e-mail]>]

Thanks Randy. Trimming down to ones where I have follow-up:

> On Dec 14, 2016, at 6:52 PM, Randall Gellens <[e-mail]> wrote:
> 
>> 
>> = Section 9.1.3.1 =
>> 
>> (1) msgid is underspecified. What is it supposed to be used for? 
>> Why is it Conditional?
> 
> It's used in draft-ietf-ecrit-car-crash.  It's Conditional because it 
> is only needed when using static messages.  It's used to indicate 
> either the static message that the vehicle should display/speak to 
> the occupants, or the set of static messages supported by the vehicle 
> (by specifying the highest supported value).  I added clarifying text 
> to the Description:
> 
>    Description:  Defined for extensibility.  Documents that make use of
>       it are expected to explain when it is required and how it it used.
> 
> Anything more explicit would require that I mention static messages, 
> which are not used in this document (they're used in car-crash), and 
> I'm afraid that would be more confusing.

The design of this seems like it could be improved, then. Since the attributes are generic and could be used to describe a variety of requests, wouldn’t it make more sense to specify a generic ID attribute in the event that a future extension defines some other action which also makes use of integer IDs? Come to think of it, isn’t this basically what element-ID is for, except that element-ID is a token rather than an integer? If the msgid attribute really only makes sense in the context of a specific extension defined elsewhere, it doesn’t make sense to define it narrowly here.

> 
> 
>> 
>> (2) For supported-values, requested-state, and element-ID, what is 
>> the expectation about where and how the permitted values will be 
>> specified?
> 
> Since these are all defined for extensibility, the expectation is 
> that the document that uses it defines this.  The car-crash draft 
> makes use of them and defines this.

I don’t see where car-crash uses requested-state or element-ID. Are you sure you need them (with a caveat about needing some kind of ID, per my comment above)?

Thanks,
Alissa