Re: [apps-discuss] "X-" revisited

[Dave CROCKER <[e-mail]>]

On 7/6/2011 1:05 PM, Peter Saint-Andre wrote:
>>>   3.  When parameter names need to be very short
>>
>> I've no idea how this requirement can justify an x- name.  (A minor
>> point, but note that x- adds two bytes to the length of the name...)
>
> Well, "x-foo" is shorter than "VND.BrandenburgInternetWorking.foo".

Mumble.  This issue seems like one that is going to take vastly more effort than 
it ought, but that's probably true for the entire topic.  (Entire topic:  X- was 
a good idea to avoid collisions with standards, but turns out to be a much worse 
idea for uses that become standards.  So, don't use X-".)

Anyhow...

"X-foo" is longer than "foo".

And I believe the real comparision to VND should be 
"X-BrandenburgInternetWorking.foo"...


>>> Implementers are easily confused.
>>
>> I don't understand how using or not using x- creates or alleviates
>> confusion in implementers.
>
> I don't either, but that was one of the objections.

OK, but whoever was/is objecting needs to explain their concerns, of course.


>>     2.  Authors of application protocol specifications SHOULD NOT
>>         mandate that all parameters without the "X-" prefix need
>>         to be registered with the IANA.
>>
>> (#2 seems odd.  I don't really understand why it is needed or what it
>> does that's significant, given the recommendation of not using x-
>> parameters ever. Is there a way of stating what is desired affirmatively?)
>
> The point is directed at the kind of thing we find in RFC 5451, which
> says that x- params MUST NOT be registered and non-x- params MUST be
> registered. That seems wrongheaded to me.

OK.  I think this reduces to a new phrasing along the lines of:

   Authors of application protocol specifications SHOULD provide extensible 
registries for all parameters and SHOULD mandate use of the registries, for all 
values of the parameters, independent of the form of the parameter names.

(The absence of any reference to X- is intentional.)

d/
-- 

   Dave Crocker
   Brandenburg InternetWorking
   bbiw.net