Re: [Slim] Negotiation issue in draft-ietf-slim-negotiating-human-language

"Randall Gellens" <> Thu, 15 February 2018 22:44 UTC

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From: "Randall Gellens" <>
To: "Bernard Aboba" <>
Date: Thu, 15 Feb 2018 14:44:09 -0800
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Subject: Re: [Slim] Negotiation issue in draft-ietf-slim-negotiating-human-language
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On 15 Feb 2018, at 4:53, Bernard Aboba wrote:

> As noted in the below thread, multiple ambiguities need to be resolved 
> in
> draft-ietf-slim-negotiating-human-language:
> In the SDP codec negotiation, multiple codecs are offered, and the 
> answerer
> selects among them, with the first codec being the preferred one.  
> Codecs
> not present in the Offer cannot be included in the Answer.
> The model proposed in draft-ietf-slim-negotiating-human-language does 
> not
> conform to this paradigm, allowing languages not present in the Offer 
> to be
> presented in the Answer, and also (previously) having an ambiguity 
> about
> whether a single language or multiple languages can be included in an
> Answer.

There are important reasons why we need to permit an answer to 
potentially select a language that was not included in the offer, e.g., 
in an emergency services case, if the PSAP does not support any of the 
languages in the offer, it still wants the call to proceed, and will 
indicate the language it supports.  (In some cases this is likely to 
result in a more or less comprehensible communication stream, e.g., in 
some Scandinavian countries where cross-border languages may be 
different enough not to be included in an offer but mutually 
comprehensible to an extent, while in some cases it may result in 
incomprehensible communication that is still of value to the PSAP in 
responding to the emergency.)

> Gunnar has proposed language to address this.  Any reason not to 
> accept his
> proposal?

Which language is this?  Can you copy the text or point to the message?