Re: [Slim] Modality preference

We’ve been working on supporting emergency services with multiple media for some time in the NENA Next Generation 9-1-1 project.

At least in the U.S., all media offered should be accepted.  The language preference will be negotiated, and based on the result, an interpreting service may be bridged into the call.
As such, a modality preference is not seen as valuable, and in fact, could be considered harmful, as the call taker should be trained to provide an initial answer in all media negotiated and react to the user’s actions thereafter.  An important characteristic of emergency services when viewed from the lens of the slim work is that the mechanisms have to work for the small percentage of cases where the normal mechanisms fail.  In this case, it would be use of a device with language and media preferences labeled by a user who isn’t the usual user of the device when an emergency call is placed.  You do NOT want to assume that the labeled preferences are actually the real preferences.  You bias your responses by the preferences, but you have to allow for variation when the call is actually answered.  So, answering in all offered media is something we would do, regardless of what the highest media preference was. 

Another reason why media preference is not really wanted is that emergency services can use other media even when the user doesn’t prefer to use them.  An audio feed for a deaf caller can be helpful to identify what is happening around the caller.  A video feed for a blind caller (if the device really made the offer) could similarly be useful.

So, I think this is not a useful capability for emergency services and if it was in the offer, I’d tend to want to ignore it and accept all media, with an initial greeting in the preferred language.

Brian

> On Jun 19, 2017, at 7:43 AM, Filip Asplund <filip.asplund@omnitor.se> wrote:
> 
> In development of emergency services the need of modality preference has been identified.
> 
> It seems to me that the functions specified in draft-hellstrom-language-grouping is what we need for emergency services.
> 
> -- 
> Best regards
> 
> Filip Asplund
> Developer
> filip.asplund@omnitor.se
> Omnitor AB
> 
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