Hitchhiker's Guide to Streaming Media: DRM
>> Looking up:””DRM”
Digital rights management (DRM) is, in broad principle, a technology that is applied to items of digital media to allow the copyright wwner to control the right of access to the content from its creation to its use regardless of the distribution and medium within which that content is disseminated. Since many copyright owners are non-technical, DRM service providers are often contracted to provide the skills required. The DRM system typically encrypts the content after it has been encoded or compressed into a format suitable for the particular distributions audience. This encryption is then part of the finally released file and this means that each use of the file will require some form of license to be granted. This may be automatic and silent as far as the end user is concerned, but the central technical system is then able to audit, control, and expire the content as needed on a usage by usage basis—and potentially at the discretion of the copyright owner.
Although there is no absolute definition, DRM is a close relation to a group of technologies that are employed in digital networks to restrict user access to digital media items called “conditional access” (CA) technologies. So close that it is often confused with CA. In the CA model, the rights owner licenses the network owner to distribute the content, and the network owner takes on the responsibility for only allowing validated users on the network to access the content. If, however, the item of content is removed from that network, conditional access systems become powerless. Also, the copyright owner is only protected by the contractual licenses with the network operator, and has not direct control over their content or visibility of its usage, as provided by DRM.
DRM is more flexible and more suited to the multi-network environment of the internet. Conditional access is more straightforward to implement and more established. CA is found predominantly in cable/satellite and now IPTV networks, where users are validated at the point of connection to the network in question by virtue of having a device (set-top box or cable modem) that uniquely identifies them.
There is also a tertiary group of technologies that, while not allowing any actual control of use or distribution of the content, can validate which version of a “master” was used. These are known as watermarking technologies. Often watermarking is used in conjunction with DRM and CA systems. That way a content owner who licenses an item of content to a particular DRM or CA provider has a way to audit any leakage from the security system put in place. Watermarks are generally, these days, only visible to technical systems that are a component part of the watermark suite.
One interesting social change recently has been that DRM is regarded in different lights in different communities. There are those who feel that DRM is a new model for an old way of doing things – so the argument goes that DRM is a way for industries that have relied on the controlled sale of “fixed” media (CD/vinyl/DVD etc) to move into the internet with their existing sale/royalty-based financial business models. There are those who argue that piracy in the instant-copy world of the internet is so inevitable that DRM is simply “clutching at straws” and a diversion from trying to develop NEW business models where sale and royalty are not features.
There are views, seemingly predominantly in the US, that DRM is a “threat” or “negative” while in Europe DRM is seen very definitely as an opportunity.
Some of these views stem from a variance in expectation. In the US there was a long discussion, post-Napster and mp3.com days, and with the SDMI initiative at the forefront, that it would be possible to introduce a DRM that was copy-proof. As such, every time a DRM emerged there was more press about how quickly it was cracked than about how it enabled a content owner to benefit.