How to open Mobile Alliance Digital Rights Management
DRM has always been a controversial technology. On the one hand, the content providers want to protect their own intellectual property, while, on the other hand, users would like to enjoy free resources. The argument of DRM exists not only in traditional music, video field (such DRM can be removed), but also in the recent appeared app store, Mobile Market, BAE Widget, etc. Those areas are also encountered similar software copyright protection problem. In this business model, the developers play the role as the content providers. Whether the software can be protected will directly affect the profitability of each developer in the market.
By using some certain security algorithm/ protocol and the security management methods, Digital Rights Management (DRM) technology can finally achieve its goal to protect the digital content (e-books, videos, audio, pictures, games, etc.). With DRM, the digital content without authorization or permission cannot be used, copied or distributed. DRM will not only control the physical transferring process of the content, but also manage and control the entire life cycle of the content. Bring the DRM technology into the mobile communications business can ensure that the digital content will spread in the mobile network, and then the content providers’ profit will be guaranteed..
There exist many DRM systems. Here are some standards: OMA DRM 1.0, OMA DRM 2.0, Marlin, Microsoft DRM, etc. Here we are going to talk about the more discussed OMA DRM.
OMA stands for Open Mobile Alliance which established in the earlier June, 2002. Its predecessors are Open Mobile Architecture Initiative supporters and WAP Forum. Later, some other organizations also joined OMA including Wireless Village, MGIF (Mobile Gaming Interoperability Forum), Sync ML Initiative, MWIF (Mobile Wireless Internet Forum), MMSIOP and LIF (Location Interoperability Forum). The main task of OMA is to collect market demand and set norms to remove obstacles in interoperable development, and to accelerate the development and application of a variety of new enhanced mobile information, communication and entertainment services and apps. OMA represents the trend of the innovation in wireless communications industry. It encourages that all members in the value chain can greatly involves in making the industry standard, so that a more complete and end to end solution will be established.
Open Mobile Alliance released OMA DRM V1.0 in September 2002, and in March 2006 the OMA DRM V2.0 was released. OMA DRM is completely open and most operators have already adopted the OMA DRM standards. DRM v1.0 standard defines a primary DRM system, and can basically achieve Forward Lock, Combined Delivery, and Separate Delivery mode in commercial needs. While other versions are more complex and secure DRM systems, such as OMA DRM2.0 can enhance the support for Combined Delivery, Separate Delivery and streaming media services, etc. OMA DRM2.1 was further enhanced based on version 2.0.
OMA DRM 1.0 is the earliest version OMA launched. Its main methods to protect the content have Forward Lock, Combined Delivery, Separate Delivery mode and Super Delivery.
Forward Lock: A media object is encapsulated in a DRM message which is transmitted to the device, and the device is allowed to use the content, but the content can not be transmitted to other devices, and the device can not modify this media object.
Combined Delivery: A permission object and a media object are encapsulated in a DRM message and are sent to the device. The device can provide content to users according to the authority objects, but users cannot modify, forward the authority objects and media objects.
Separate Delivery: The content object is packed in a special DRM Content Format using symmetric encryption technology and users have to use Content Encryption Key (CEK) to access the media content. CEK is stored in the copyright object. In this way, the content can be transmitted through the non-secure path and the copyright content needs to be transmitted with a more secure transmission path.
Super Delivery: This is a special application for delivery. In this mode, you can send a media object through any possible way between ends, but the copyright object can only be obtained by WAP Push from the copyright Publisher. This will encourage the users to easily share contents with each other without endangering any copyright protection conditions in business mode.