Troubleshooting common issues in easyDCP KDM Generator+

easyDCP KDM Generator+: Step‑by‑Step WorkflowThis article walks through a complete workflow for creating Key Delivery Messages (KDMs) using easyDCP KDM Generator+. It’s written for DCP (Digital Cinema Package) operators, post‑production professionals, and delivery engineers who need a reliable, repeatable process to securely deliver decryption keys to cinema servers. The guide covers prerequisites, setup, stepwise procedures, common options, best practices, and troubleshooting.

What is easyDCP KDM Generator+?

easyDCP KDM Generator+ is a professional application used to create KDMs — secure, time‑limited XML files that deliver the decryption keys (Content Keys) required to play encrypted DCPs on cinema servers. KDMs bind a Content Key to a specific theater’s server by using the server’s public certificate (KDM recipient certificate) and define an activation window (validity period).

Prerequisites and terminology

Before creating KDMs, ensure you have:

• The encrypted DCP’s Content Key(s) or the easyDCP transfer/package that includes them.
• The recipient cinema server’s X.509 certificate (often called KDM certificate or server certificate) and its corresponding recipient name.
• The Content Creator’s (sender) X.509 certificate and private key (used to sign the KDM).
• Clock/time synchronization on both sender and recipient systems.
• Knowledge of the required validity window (start and end dates/times) for playback.

Key terms:

• Content Key — the symmetric AES key used to encrypt essence within the DCP.
• KDM (Key Delivery Message) — an encrypted XML that packages Content Key(s) for a recipient.
• SRM (Security Rules/Management) — theater policies, sometimes influencing KDM usage.

Installation and initial setup

1. Install easyDCP KDM Generator+ following the vendor’s instructions for your OS (macOS/Windows).
2. Launch the app and register/activate with your license key.
3. Configure time zone and clock synchronization to avoid validity window mismatches.
4. Import your signing certificate and private key (Content Creator certificate). In easyDCP this typically appears under the keys/certificates or preferences area.
   • Ensure the private key is accessible and protected; KDM signing requires access to it.
5. Create or organize a folder structure for DCPs, recipient certificates, and generated KDMs for version control and traceability.

Step‑by‑step KDM creation workflow

Below is the typical workflow inside easyDCP KDM Generator+. Menu names and exact button labels may vary slightly by version.

1. Open easyDCP KDM Generator+.
2. Create a new KDM project or session (File → New KDM or similar).
3. Import the DCP or the key information:
   • If you have an easyDCP transfer or DCP package, import it. The application reads the Composition Play List (CPL) and extracts Content IDs and Key IDs automatically.
   • Alternatively, manually enter the Content Key IDs (KIDs) and track IDs if necessary.
4. Add recipient certificates:
   • Click Add Recipient or Import Certificate.
   • Load the recipient’s X.509 certificate (.pem, .cer, .der formats are typically accepted).
   • Assign a recognizable label (e.g., “CinemaName_Server123”) for traceability.
5. Select validity window:
   • Set the “Not Before” (activation) and “Not After” (expiration) dates/times.
   • Consider timezone differences; many systems expect UTC. Confirm target server requirements.
6. Assign which Content Key(s) to include for each recipient:
   • By default, the app will include all KIDs associated with the imported CPL.
   • For granular control, tick only the specific KIDs required.
7. Configure optional settings:
   • KDM Content Title or Description field for internal tracking.
   • Custom metadata if your workflow or recipient requires it.
   • Logging level and output folder for the generated KDM files.
8. Sign the KDM:
   • Choose the signing certificate (your Content Creator certificate) and confirm the private key’s passphrase, if prompted.
   • The app signs and encrypts the KDM per DCI/CPL standards.
9. Export and save:
   • Save the generated KDM(s) to a secure folder.
   • easyDCP often packages KDMs as .kdm or .xml files; verify extensions expected by recipients.
10. Verify KDM integrity:
    • Use the built‑in validation (Validate KDM) if available.
    • Check that KIDs, recipients, and validity windows match expectations.
11. Deliver securely:
    • Transfer KDMs via secure email, SFTP, or a KDM delivery portal as specified by the recipient.
    • Use secure channels and verify recipient identity before transmitting.

Batch processing (multiple recipients / titles)

easyDCP KDM Generator+ supports batch creation of KDMs, useful for wide distribution:

• Prepare a CSV or spreadsheet mapping recipient certificate filenames/names to validity windows and KID lists (if your version supports CSV import).
• Use the batch import feature to create KDMs for hundreds of recipients in one run.
• Validate a sample of generated KDMs before distributing all.

Example CSV columns commonly supported:

• recipient_cert, recipient_name, not_before, not_after, kid_list, title

Best practices

• Always test one KDM with the recipient server before mass distribution.
• Keep private signing keys in a secure Hardware Security Module (HSM) if available.
• Log all generated KDMs with recipient details, validity windows, and transmission records.
• Use short, well‑defined validity windows to minimize exposure; avoid overly long KDM durations unless required.
• Maintain synchronized, reliable NTP time across systems.
• Archive KDMs and associated metadata for at least the duration required by your business/legal needs.

Common issues and troubleshooting

• “Invalid recipient certificate” — ensure the cert is the server’s public key and formatted correctly (.pem/.cer). Convert DER ↔ PEM if needed.
• “KDM not accepted by server” — verify that the recipient’s certificate fingerprint/KID matches what the server expects; check time zone and clock skew.
• “Missing KIDs” — re‑import the CPL or manually add KIDs; confirm DCP contains encrypted tracks with associated KIDs.
• “Signature error” — confirm you used the correct signing certificate and private key; check passphrase and certificate validity.
• “Batch import errors” — check CSV formatting, mandatory columns, and that file paths to certificates are correct.

Example command/automation snippet

If you automate aspects with scripting (outside easyDCP’s GUI), maintain strict handling of private keys and use secure temporary storage. GUI automation options differ by environment; consult easyDCP’s docs for command‑line tools or APIs if available.

Security and compliance notes

KDMs are a sensitive element of secure content delivery. Treat recipient certificates and your signing private key as high‑value assets. Follow studio or distributor security requirements (DRM rules, key rotation policies, chain of custody).

Final checklist before distribution

• Confirm correct KIDs are included.
• Verify recipient certificates and labels.
• Double‑check validity window times and time zones.
• Sign and validate KDMs.
• Use secure delivery channels and keep logs.

This workflow covers the practical steps to generate, validate, and deliver KDMs using easyDCP KDM Generator+. If you’d like, I can create a printable checklist, a CSV template for batch sends, or step‑by‑step screenshots tailored to a specific easyDCP version.