Subject: [Slim] Claim of consensus on meaning of RFC 4566 "lang" attribute

From: Bernard Aboba <[email-masked]>
Date: Thu, 7 Apr 2016 13:03:58 -0700

In today's meeting, we had folks pointing to discussions of the meaning of
the "lang" attribute in previous meetings (in MMUSIC).  Can people post
pointers to those previous discussions?

---

From: Bernard Aboba <[email-masked]>
Date: Thu, 7 Apr 2016 13:08:30 -0700

Here is what we have in RFC 4566bis (
https://tools.ietf.org/html/draft-ietf-mmusic-rfc4566bis-16#page-36):

   Multiple lang attributes can be provided either at session or media
   level if the session or media has capabilities to use multiple
   languages, in which case the order of the attributes indicates the
   order of preference of the various languages in the session or media,
   from most preferred to least preferred.

   As a session-level attribute, lang specifies a language capability
   for the session being described.  As a media-level attribute, it
   specifies a language capability for that media, overriding any
   session-level language(s) specified.

   The "lang" attribute value must be a single [RFC5646
<https://tools.ietf.org/html/rfc5646>] language tag in
   US-ASCII.  A "lang" attribute SHOULD be specified when a session is
   of sufficient scope to cross geographic boundaries where the language
   of recipients cannot be assumed, or where the session has
   capabilities in languages different from the locally assumed norm.

   Events during the session can influence which language(s) are used,
   and the participants are not strictly bound to only use the declared
   languages.

---

From: Gunnar Hellström <[email-masked]>
Date: Thu, 7 Apr 2016 23:11:32 +0200

I had a discussion in mmusic in October 2015 under the subject:
"Clarification for multiple lang attributes in rfc4566bis"
Starting at:
https://mailarchive.ietf.org/arch/search/?email_list=mmusic&qdr=y&q=rfc4566bis

/Gunnar

Den 2016-04-07 kl. 22:08, skrev Bernard Aboba:
> Here is what we have in RFC 4566bis 
> (https://tools.ietf.org/html/draft-ietf-mmusic-rfc4566bis-16#page-36):
>
>     The "lang" attribute value must be a single [RFC5646 <https://tools.ietf.org/html/rfc5646>] language tag in
> On Thu, Apr 7, 2016 at 1:03 PM, Bernard Aboba <[email-masked] 
> <mailto:[email-masked]>> wrote:
>
>     In today's meeting, we had folks pointing to discussions of the
>     meaning of the "lang" attribute in previous meetings (in MMUSIC). 
>     Can people post pointers to those previous discussions?
>
>
>
>
> _______________________________________________
> SLIM mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/slim

-- 
-----------------------------------------
Gunnar Hellström
Omnitor
[email-masked]
+46 708 204 288

---

From: Randall Gellens <[email-masked]>
Date: Thu, 7 Apr 2016 14:40:17 -0700

> Can people post pointers to those previous discussions?

There were various ad-hoc discussions going back a number of years. 
I'd have to do a search of my email archives to find them all, but I 
do have notes from a meeting in 2013 where some combination of the 
following people attended (all of whom indicated interest in 
participating; I sent notes from the discussion to all of them, but 
didn't note who was there): Peter Saint-Andre, Flemming Andreasen, 
Gunnar Hellstrom, Brian Rosen, Keith Drage, Peter Saint-Andre, Brian 
Rosen, Hannes Tschofenig, Ari Keranen, Alexey Melnikov, John C 
Klensin, Harald Alvestrand, Andrew Hutton, Pete Resnick, Dale Worley, 
Randall Gellens.  The notes indicate that we agreed that:

	New SDP attribute(s) vs re-use of existing 'lang' attribute:
		- Existing attribute semantics are unclear so should be avoided
		- Minting new attributes is cheap

-- 
Randall Gellens
Opinions are personal;    facts are suspect;    I speak for myself only
-------------- Randomly selected tag: ---------------
C++ is pronounced "C cross cross."  Not one but two crosses to bear: C
and a broken interpretation of object-orientation.

---

From: Gunnar Hellström <[email-masked]>
Date: Fri, 8 Apr 2016 00:58:31 +0200

Bernard,
Also the discussion we had in SLIM in October explains the history of 
the 'lang' attribute.
Starting with mail with subject "The use of multiple lang attributes in 
SDP" on 2015-10-04.

Linking it back to a need to describe language negotiation in RFC 2277.

This background makes it clear that the intention was for selection and 
negotiation.

/Gunnar

Den 2016-04-07 kl. 23:11, skrev Gunnar Hellström:
>> On Thu, Apr 7, 2016 at 1:03 PM, Bernard Aboba 
>> <[email-masked] <mailto:[email-masked]>> wrote:
>>
>>     meaning of the "lang" attribute in previous meetings (in
>>     MMUSIC).  Can people post pointers to those previous discussions?
>>
>>
>>
>>

---

From: Martin J. Dürst <[email-masked]>
Date: Fri, 8 Apr 2016 15:13:58 +0900

I wasn't there, so I can't speak from experience, but

On 2016/04/08 06:40, Randall Gellens wrote:

> There were various ad-hoc discussions going back a number of years. I'd
> have to do a search of my email archives to find them all, but I do have
> notes from a meeting in 2013 where some combination of the following
> people attended (all of whom indicated interest in participating; I sent
> notes from the discussion to all of them, but didn't note who was
> there):

> Peter Saint-Andre,

> Flemming Andreasen, Gunnar Hellstrom,
 > Brian Rosen,

> Keith Drage,

> Peter Saint-Andre,
> Brian Rosen,

some people paid for doubles, or there were too many mirrors in the 
room, or some people already had a bit too much booze, or whatever.

Regards,    Martin.

> Hannes Tschofenig,
> Ari Keranen, Alexey Melnikov, John C Klensin, Harald Alvestrand, Andrew
> Hutton, Pete Resnick, Dale Worley, Randall Gellens.  The notes indicate
> that we agreed that:
>

---

From: Brian Rosen <[email-masked]>
Date: Fri, 8 Apr 2016 09:24:46 -0300

Yes, of course.  I had a double!

I was there, twice!

> On Apr 8, 2016, at 3:13 AM, Martin J. Dürst <[email-masked]> wrote:
> 
> some people paid for doubles, or there were too many mirrors in the room, or some people already had a bit too much booze, or whatever.
> 
> Regards,    Martin.
> 
>> Hannes Tschofenig,

---

From: Randall Gellens <[email-masked]>
Date: Fri, 8 Apr 2016 05:38:16 -0700

At 3:13 PM +0900 4/8/16, Martin J. Dürst wrote:

>  some people paid for doubles, or there were too 
> many mirrors in the room, or some people 
> already had a bit too much booze, or whatever.

Sorry, I coped the names from the email 
recipients and neglected to do a duplicate 
removal operation (left as an exercise for the 
reader).

-------------- Randomly selected tag: ---------------
Look Bruce, the bat signal!!!

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From: Gunnar Hellström <[email-masked]>
Date: Sun, 10 Apr 2016 21:44:56 +0200

The very origin of the 'lang' sdp attribute is its announcement last in 
this e-mail from 1997-11-23
https://mailarchive.ietf.org/arch/msg/mmusic/hEU4yCmc31ib4Vk23aCQPfm5QvQ

It is said to fulfill a requirement from a draft that later became RFC 2277.

/Gunnar

Den 2016-04-08 kl. 00:58, skrev Gunnar Hellström:
> Starting with mail with subject "The use of multiple lang attributes 
> in SDP" on 2015-10-04.
>
> This background makes it clear that the intention was for selection 
> and negotiation.
>
> /Gunnar
>
>
>