Digital rights management (DRM) is a complex world with many different rabbit holes to venture into. The good news is we’ve done a lot of heavy lifting by navigating in, out, and around many of these complex situations to provide you with an overview and the knowledge you need to make the best decisions for the security and playback experience of your content.
This blog post showcases our latest findings on digital rights management for Samsung Tizen TVs. With the Connected TV viewership increasing steadily, we’re excited to share this information with you, and we’re confident that you’ll find it useful. Additionally, if you want to see more devices analyzed, tell us which ones by joining our developer community and starting a discussion.
So, with no further wait, let’s get into it!
DRM & Cipher Modes
To start with, it may be worth having a refresher on the types of DRM and the most common DRM technologies available on the market. In one of our previous blog posts, you can find an in-depth outline of the types of DRM, available DRM offerings, and how they work. To quote a part of it regarding how content is encrypted:
“Standard content encryption is done according to the Advanced Encryption Standard (AES), using 128-bit keys and a Cipher Block – usually either Counter Mode (CTR) or Cipher Block Chaining (CBC). These two modes differentiate how a payload is encrypted”.
DRMs fundamentally apply the AES encryption algorithm, which supports various cipher blocks, with CTR, and CBC being the standard. The ISO standard ISO/IEC 23001-7 defines the four common encryption modes.
Table of common encryption details
In the table below, you can see which DRM supports each cipher block.
DRMs and the ciphers supported
As you can see, Widevine and PlayReady support CTR, and CBC for specific devices, while Fairplay only supports CBC. In the next section, we’ll take a closer look at the support for MSE/EME stack specifically, as TV DRM & Cipher support can vary between their native player and the MSE/EME player.
Tizen Support for Cipher Modes
With Bitmovin’s Stream Lab and our work with Samsung, we have detailed all of our findings/results in the matrix below:
Samsung TVs and the ciphers each MSE/EME supports
As a rule of thumb, for TVs older than 2019, CBC support is limited. Another rabbit hole worth watching out for in regards to every TV is if it indicates support for CBC, it is worth validating it’s for MSE/EME stack and NOT the native player stack.
What is the best DRM setup for Samsung Tizen?
You will notice from the table above that Widevine + CTR cipher covers a large proportion of the Tizen TVs. You can use the Bitmovin Encoding CENC API encryptionModeCTR to package video with Widevine + CTR. Check out this tutorial to see how you can set it up.
Looking forward, Tizen TVs for 2022 and beyond look like they are heading in the CBCS-friendly direction. Hopefully, in about 5 years, when 2022 TVs become the standard version, it might be possible to have a single copy for all three DRMs.
On a related note, if you intend to serve only CBCS devices, Bitmovin Encoding CENC API also allows you to output a single copy for all three DRMs just by specifying encryptionModeCBC.
Additionally, you may find it helpful to have the following links at your disposal: the Playready CBCS documentation and the Tizen TV DRM specification.
What devices would you like analyzed next?
That wraps up the Samsung DRM cipher analysis. Let us know if you found it useful and if there is more information or guidance we can help you with by starting a discussion on the Bitmovin developer community.
Also, while you’re there, let us know which additional devices you’d like this analysis done for next, and if you want, you can also test out the Bitmovin Player for yourself with our 30-day free trial.
