Specifications

White Paper V800-Vodafone V802SE
41 August 2004
DRM
Digital Rights Management, DRM, is a technology
that enables secure distribution, promotion, and
sale of digital media. Examples of such content
include images, wallpapers and screen savers with
themes from films, ringtones from musical artists,
and branded games. In other words, content pro-
viders can control how users may use different
types of content in devices, such as mobile
phones, smartphones or PDAs. Content providers
can also control the use of content in related serv-
ices, such as MMS.
Sony Ericsson is actively focusing on technology
standardization for the DRM concept, and supports
the ongoing standardization work and activities of
the OMA (Open Mobile Alliance). Sony Ericsson is
fully committed to open standard solutions in the
mobile environment and is a principal driver of
many open standard initiatives. This will ensure the
interoperability of mobile terminals in the DRM area
and also result in a strong, competitive DRM stand-
ard.
How DRM works
The control of the content in digital media is exe-
cuted by defining usage rights for the content. The
usage rights give the content providers flexibility in
the way they can publish and sell content. Rights
can be defined so that a picture can be used by
subscribers only, and rights can be defined so that
a ringtone can be played only a limited number of
times or for a limited period of time. Rights can also
be defined so that the user is not able to forward
content to other devices.
Packaging of rights and content
Rights and content can be packaged together and
delivered to the device as one DRM package. As
an alternative, content can be delivered to the
device first, followed by the rights later being
pushed to the device, for example via SMS. The
kind of service and business model adopted by the
content provider determines how the content and
rights should be packaged and delivered to the
device.
DRM packager
A DRM packager is typically included in the soft-
ware used by the content provider. It is used to cre-
ate the DRM package that is delivered to the
device, including content and associated rights. In
the device, the content of the DRM package is
made available to the user according to the rights.
If the rights permit the user to play a ringtone ten
times, the device will keep track of the number of
times the ringtone is played, and notify the user
when the ringtone has been used for the tenth time.
A Sony Ericsson DRM Packager is available from
the Sony Ericsson Developer World at
www.sonyericsson.com/developer
.
Protection properties
Content protection according to the OMA DRM
standard gets special properties. Content with for-
ward lock protection has the “Send to” option disa-
bled, which prevents it from further distribution.
Unless the content is encrypted, the user cannot
copy DRM content to other devices since the Send
to option is disabled for pictures, ringtones, etc.
that are OMA DRM protected. Content providers
may choose to protect some content, but leave
some content unprotected.
Package and delivery
The OMA DRM standard defines two ways to pack-
age and deliver rights and content to a device:
combined or separated.
Combined delivery
Rights and content are packaged together into one
DRM Package and delivered to the device. In the
simplest case, no special rights are defined. The
content is just put into a DRM package, thus pro-
tected from being copied out from the device by
the user. This special case is called forward-lock.
It is useful for all types of content that the provider
wants to charge for.
Separate delivery
Rights are defined and sent in a push message.
The content is encrypted and made available for
users to download to their devices. The decryption
key is put into the rights file. Since the content is