marco_marcelli writes with a link to the founder and chairman of MPEG, Leonardo Chiariglione, replying to Steve Jobs on DRM and TPM. After laying the groundwork by distinguishing DRM from digital rights protection, Chiariglione suggests we look to GSM as a model of how a fully open and standardized DRM stack enabled rapid worldwide adoption. He gently reminds Jobs (and us) that there exists a reference implementation of such a DRM stack — Chillout — that would be suitable for use in the music business.