SMPTE 430-1:2017

This specification defines a “Key Delivery Message” (KDM) for use in Digital Cinema (D-Cinema) systems. The KDM has been designed to deliver security parameters and usage rights between D-Cinema content processing centers (e.g. from post production to distribution, or from distribution to exhibition). The KDM carries fundamentally three information types:

• Content keys for a specified Composition Play List (CPL).
• Content key parameters — primarily the permitted key usage date/time window.
• The Trusted Device List (TDL) which identifies equipment permitted to use the content keys.

The KDM is based on the D-Cinema generic Extra-Theater Message (ETM) format [ETM]. It uses XML to represent the information about the content decryption keys and TDLs, and provides security using standardized XML encryption and signature primitives. The KDM message uses X.509 digital certificates, specified in [D-Cinema Digital Certificate], to provide authentication and trust.