Block 4. DRM and Content Protection

What is DRM in video streaming? How content protection encrypts video, what DRM actually protects, the analog hole it can't stop, and when you need it.

Widevine, PlayReady, and FairPlay compared: which devices each DRM covers, what the security levels mean for 4K, and why every platform needs all three.

Multi-DRM explained: encrypt once with cbcs, then license Widevine, PlayReady, and FairPlay per device. The workflow, the cost, and build vs buy.

CENC, CTR, and CBCS explained: the two AES schemes behind multi-DRM, why FairPlay needs cbcs, and why you should encrypt your catalog once with cbcs.

How a player gets the key to decrypt: the EME license flow, license servers and the entitlement proxy, key rotation, and where each secret lives.

How a DRM license enforces rentals, offline playback, HDCP output control, and resolution caps — turning studio terms into device-enforced rules.

What Encrypted Media Extensions (EME) is, how browser DRM works, and which CDM lives in Chrome, Edge, Firefox, and Safari — plus the multi-DRM rule.

PlayReady 4.8 reaches Samsung Tizen TVs in 2026 with a new certificate revocation list. What breaks, the model-year cipher map, and how to test it.

Forensic watermarking hides a per-viewer ID in the video so a leak traces to its source. How A/B watermarking works, costs, and when it's required.

How OTT anti-piracy operations work: monitor for leaks, trace them with watermarks, and act via DMCA takedown, EU notice, or live dynamic blocking.

The full DRM and content-protection reference architecture for OTT: the boundary, encrypt-once cbcs, multi-DRM licensing, EME, and watermarking.