Re: Network Information API

On Sun, Dec 8, 2013 at 2:43 PM, Mounir Lamouri <mounir@lamouri.fr> wrote:

> On Mon, Dec 9, 2013, at 0:21, Marcos Caceres wrote:
> > From the data we collected, the main cases appear to be:
> >
> > * warn the user that this could cost them money (bbc website, only works
> > on Safari in iOS)
> > * give the user control as to whether large uploads/downloads should
> > happen over cellular.
> > * Prevent accident data transfer over cellular, which could use up of the
> > user's download quota and/or cost them money.
>
> As I see it, UC does not mean "what people do" but "what people could do
> if they have that tool". For the moment, it is fairly hard to guess the
> connection quality of your users so websites/apps will use the best tool
> they have: cellular vs wifi. But as said multiple times, there is fast
> and uncapped cellular and slow and capped wifi. Why the iTunes store
> prevent users to do large downloads over their cellular connections?
> Likely because users might end up paying without knowing it and complain
> to Apple and also because the download might be so slow that it could
> affect the user experience.
>
> I see UC for bandwidth. Basically, anything related to content quality
> negotiation:
> - default image quality: you visit Google+, Facebook or Flickr and
> depending on your device, you will see an image that will be fast enough
> to be downloaded (yes, this is intended to be solved by responsive
> images too);
>

Since content image loading happens at the latest when HTMLImageElement is
parsed, loading it with scripts in order for them to use bandwidth
evaluation to decide which resource to download will introduce a
significant delay to the image loading process. Providing the browser with
possible resources and letting it make that decision much earlier, is a
much better option. A responsive images solution will provide that.

 - default video quality: Netflix currently shows a low quality video
>  and improve it until they reach a quality that match what the user can
>  download. It would be better for the user perspective if the first
>  video quality was closer to what they would expect;
> - default texture in a game: a game might want to show LD quality
> because your system can't handle HD quality but also because downloading
> the assets would be too slow;
> - downloading the email bodies without monopolizing the bandwidth.
>

Each one of these cases could very well use heuristics based on Navigation
Timing and Resource Timing to decide which resource they want to download.
For resources where it makes sense, they can also split the download into
ranges and measure the download time of each range, deciding whether to
continue with the same quality, or move to a lower/higher one. For the
email bodies case, they can just download bundles, and stop when one of the
bundles takes too long to download.

And they can do that today without any new APIs.


>
> For what its worth, we are having this discussion every 6 months. Some
> UC are listed in the specification I believe and could definitely be
> found in the list archives.
>
> Cheers,
> --
> Mounir
>
>