Re: [xmpp] Brian Haberman's Discuss on draft-ietf-xmpp-6122bis-23: (with DISCUSS)

[Brian Haberman <[e-mail]>]

Hi Peter,

On 6/10/15 1:22 PM, Peter Saint-Andre - &yet wrote:
> Hi Brian, thanks for the review.
> 
> On 6/10/15 8:28 AM, Brian Haberman wrote:
>> Brian Haberman has entered the following ballot position for
>> draft-ietf-xmpp-6122bis-23: Discuss
>>
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>>
>> Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
>> for more information about IESG DISCUSS and COMMENT positions.
>>
>>
>> The document, along with other ballot positions, can be found here:
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>>
>>
>>
>> ----------------------------------------------------------------------
>> DISCUSS:
>> ----------------------------------------------------------------------
>>
>> This should be a relatively straightforward DISCUSS and may not result in
>> any changes to the document...
>>
>> I see this definition in the draft:
>> domainpart   = IP-literal / IPv4address / ifqdn
>>                       ;
>>                       ; the "IPv4address" and "IP-literal" rules are
>>                       ; defined in RFC 3986, and the first-match-wins
>>                       ; (a.k.a. "greedy") algorithm described therein
>>                       ; applies to the matching process
>>                       ;
>>                       ; note well that reuse of the IP-literal rule from
>>                       ; RFC 3986 implies that IPv6 addresses are enclosed
>>                       ; in square brackets (i.e., beginning with '[' and
>>                       ; ending with ']')
>>
>> RFC 3986 was updated by RFC 6874 to allow zone identifiers in address
>> literals when the address is not globally scoped.  Was this considered in
>> the drafting of this update?  RFC 6874 updates the ABNF to be:
>>
>>        IP-literal = "[" ( IPv6address / IPv6addrz / IPvFuture  ) "]"
>>        ZoneID = 1*( unreserved / pct-encoded )
>>        IPv6addrz = IPv6address "%25" ZoneID
>>
>> I suspect you will get varying results depending on how many implementers
>> follow the Updates chain of 3986.
> 
> My apologies, I forgot that RFC 6874 updated RFC 3986 in this regard. If
> we keep this text, I agree that we should point to RFC 6974.

Agreed.

> 
> RFC 6122 had this text:
> 
>                       ; note well that reuse of the IP-literal rule
>                       ; from RFC 3986 implies that IPv6 addresses are
>                       ; enclosed in square brackets (i.e., beginning
>                       ; with '[' and ending with ']'), which was not
>                       ; the case in RFC 3920
> 
> We could, I suppose, remove this text entirely since it was meant to
> give implementers notice about the change from RFC 3920 to RFC 6122.
> However, I think it's always good to keep implementation notes of this
> kind. So, looking at this again, I think I would change it to:
> 
>                      ; the IPv4address and IP-literal rules are
>                      ; defined in RFC 3986 and RFC 6874 respectively,
>                      ; and the first-match-wins (a.k.a. "greedy")
>                      ; algorithm described in Appendix B of RFC 3896

s/3896/3986/

>                      ; applies to the matching process
>                      ;
>                      ; note well that reuse of the IP-literal rule from
>                      ; RFC 6874 implies that IPv6 addresses are enclosed
>                      ; in square brackets (i.e., beginning with '[' and
>                      ; ending with ']'), which was not the case with
>                      ; the definition of the XMPP address format in
>                      ; RFC 3920
> 
> However, I might want to move the last paragraph to an implementation
> note (not an ABNF comment) so that we have a proper reference to RFC 6874.

I agree that a proper reference to 6874 would be useful.  Is there any
need to mention the potential for a literal to include the zone id?

Brian