Re: [EME] Netflix’s secure release is unreliable without tamper-proof secure persistent storage and/or delayed shutdown

On Fri, Jun 12, 2015 at 4:32 AM, Henri Sivonen <hsivonen@hsivonen.fi> wrote:

> On Fri, Jun 12, 2015 at 3:19 AM, David Dorwin <ddorwin@google.com> wrote:
> > Unless there
> > is a solution that can be equally and reliably implemented across the
> wide
> > breadth of web platform clients, we do not believe secure release has a
> > place in EME.
>
> Considering these alternatives...
>
>  1) No secure release in either CDMs or EME.
>
>  2) Secure release support in CDMs but not in EME; JS has to dispatch
> on flags inside the supposedly opaque EME message data or on
> vendor-specific EME extensions.
>
>  3) Secure release support in CDMs and in EME.
>
> ...it seems to me that from a UA perspective, #1 is the best option,
> but #3 is better than #2.
>
> I'm worried that by withholding enum values from the EME spec to try
> to force #1, we may not actually end up with option #1 but with option
> #2. And if that happens, we'd be better off with option #3. To end up
> with option #1, the right method isn't withholding enum values from
> the spec but showing that there's a better way such that those who now
> want to do secure release no longer want to do it.
>
> I think there are parallels to the "individualization-request" issue
> (though that feature is truly optional in the sense that if you have a
> CDM that doesn't do download-based individualization or you have a CDM
> that does it out of band, then you don't need to emit messages of that
> kind).
>

I understand how you might see parallels, but the issues are *very*
different. This isn’t just about an "enum value" that is truly optional and
useful to some implementations. This is about defining a session type - an
entire mode - for simple online streaming along with the requirements it
imposes on user agent architectures, as described in
https://lists.w3.org/Archives/Public/public-html-media/2015Jun/0029.html.

I agree with your point about a better way and hope we can all work
together on this.