A one-page reference to choose an encryption scheme before you lock a packaging config or sign a DRM contract: the two schemes that ship (cenc = AES counter mode read by Widevine and PlayReady; cbcs = AES chaining mode with a 1:9 pattern read by all three including FairPlay), the cbcs-everywhere rule and the cenc-only black-screen warning, the four signaling boxes (schm, tenc, senc, pssh) and what default_KID means, the packaging decision (cbcs default; cenc only as a deliberate legacy fallback
Download free PDF
The handbook · 7 volumes
Fora Soft Video Engineering Handbook
This reference helps you choose cenc or cbcs before you lock packaging, explains the cbcs-everywhere rule, the four signaling boxes and default_KID. Our seven-volume handbook covers the full video stack; start with Volume 3 for DRM and players, then Volume 2 for CMAF packaging and Volume 1 for encoding. Written by Nikolay Sapunov, CEO at Fora Soft.
Choosing between cenc and cbcs before you sign a DRM contract?
Send us your device list and packaging setup, and we will confirm the scheme, signaling boxes and key handling for every DRM. 250+ video products shipped since 2005.
You get a realistic estimate, technical recommendations and next steps. Free, no obligations.
