What you’ll learn
- What a DKDM is used for.
- The difference between a KDM and DKDM.
- How to open the KDM / DKDM Creator.
- How to define the validity period.
- How to select the encrypted DCP key.
- How to load the recipient mastering-system certificate.
- How to generate DKDMs for one or several certificates.
What is a DKDM?
A DKDM, or Distribution Key Delivery Message, allows another DCP authoring or mastering system to decrypt an encrypted DCP.
The DKDM is valid only between its configured Start Time and End Time.
The recipient can use the DKDM to open and work with the encrypted DCP during that validity period.
KDM versus DKDM
| Message type | Recipient | Typical use |
|---|---|---|
| KDM | Cinema server or projector | Exhibition |
| DKDM | DCP authoring or mastering system | Post-production and mastering |
Before you begin
You need:
- An encrypted DCP.
- A usable decryption key for that DCP.
- The public certificate for the recipient authoring or mastering system.
- The required Start Time and End Time.
- A destination folder for the generated file or files.
Open the KDM / DKDM Creator
There are two ways to open the Creator:
- Choose File > Create KDM / DKDM.
- Right-click an unlocked encrypted Timeline and choose Create KDM / DKDM.
When opened from a Timeline, DaCaPo automatically uses the decryption key associated with that Timeline.
When opened from the File menu, a compatible key source must be provided manually.
Add optional Annotation Text
The optional Annotation Text field can be used to add a descriptive note to the generated DKDM.
This field may be left empty.
Set the validity period
The Start Time and End Time fields define when the DKDM is valid.
The recipient system will only be able to decrypt the content during the specified validity period.
Select the DCP Key
The DCP Key is the encryption key used to create the DKDM.
When the Creator is opened from a Timeline, the key is loaded automatically from the Timeline's encryption slot.
When opened from the File menu, provide a compatible key source manually.
Compatible sources include:
.dcpkey- DKDM
- Digest XML
- Other supported key files
Select the Server Certificate
Select the public certificate for the target DCP authoring or mastering system.
Supported certificate formats include:
- PEM
- CRT
- DER
Create DKDMs for multiple certificates
A folder containing multiple certificates can also be selected.
In that case, DaCaPo generates a separate DKDM for each certificate found in the folder.
Choose the destination
Select the folder where the generated DKDM file or files should be saved.
Generate the DKDM
Click Generate to create the DKDM.
The generated file or files can then be delivered to the recipient system together with the encrypted DCP.
Common problems
No DCP Key is available
Open the Creator from an unlocked encrypted Timeline or provide a compatible key source manually.
The recipient cannot use the DKDM
Confirm that the correct authoring or mastering-system certificate was selected and that the DKDM validity period is active.
The DKDM is not yet valid
Check the configured Start Time.
The DKDM has expired
Create a new DKDM with an appropriate End Time.