Re: Campaign for position of chair and mandate to close this community group

On Thu, Jan 16, 2014 at 8:20 AM, Henri Sivonen <hsivonen@hsivonen.fi> wrote:

> On Thu, Jan 16, 2014 at 5:32 PM, Henri Sivonen <hsivonen@hsivonen.fi>
> wrote:
> > That is, are the Android apps that don't rely on a device-resident
> > PlayReady component and that roll their own PlayReady implementation
> > using PlayReady Porting Kit without Microsoft PlayReady Client SDK for
> > Android? If there are, do they work on any Android system (including
> > vanilla AOSP)?
>
> Or in a less cryptic way:
>
> There are cases where Microsoft (as I understand it, I haven't
> actually tried signing up for the SDKs, but I imagine you get object
> code from MS in the SDK cases) provides the PlayReady object code:
>  * System PlayReady on Windows 8.x
>  * Silverlight for XP, Vista, 7, 8 and Mac
>  * Microsoft PlayReady Client SDK for Android
>  * Microsoft PlayReady Client SDK for iOS
>  * PlayReady PC SDK (for Windows Vista SP1 and Windows 7)
>
> Then there's the case where Microsoft provides PlayReady source code:
>  * PlayReady Device Porting Kit
>
> Now, it's clear that if a platform is one where Microsoft provides an
> SDK (Windows Vista+, Android, iOS), then it's possible to license
> PlayReady for that platform. Also, it appears that if the platform is
> locked-down against user-installable software, as "embedded Linux"
> stuff tends to be, or there's a kernel-unreachable place to stick the
> PlayReady implementation into (e.g. TrustZone), it's possible *for the
> vendor of the platform* to license PlayReady for that platform by
> doing the porting using PlayReady Device Porting Kit.
>
> But what about platforms for which Microsoft doesn't provide an SDK
> and that aren't locked down against user-installable software in
> general and that don't provide a TrustZone-like locked down second
> domain of computing? It seems that for many people on this list,
> desktop Linux is their top concern that fits this description. But OS
> X is more mainstream and it's still in this category. Moreover, from
> Silverlight, we see that *Microsoft* can permit itself to ship
> PlayReady for OS X. But what about a non-Microsoft entity that isn't
> the platform vendor (Apple in this case), either?
>

Thanks for the less cryptic version ;-)

I don't know if this is the whole answer - you'd have to ask Microsoft -
but likely it comes down to whether your implementation satisfies the
robustness rules. One might think that so long as you meet the rules, it
doesn't matter how, whether that is through Tivoization, Trusted Execution
Environment or software obfuscation. Or, at least, if it does matter how
doesn't that mean the rules are incomplete ? I am aware of cases where
software obfuscation has been used to meet DRM robustness rules on non
Tivo-ized platforms without a TEE.



...Mark





>
> That's why it's interesting to ask about OS X.
>
> (Of course, it's pretty bizarre that the question whether a component
> can be licensed from Microsoft is relevant to the practical
> implementability of a W3C spec.)
> --
> Henri Sivonen
> hsivonen@hsivonen.fi
> https://hsivonen.fi/
>
>