Tape and file labeling controls: In operations using header/trailer labels, what information is typically included on trailer labels to aid identification and retention management?

Introduction / Context:
In traditional batch and archive operations, header and trailer labels on tapes or logical files provide essential metadata. They help operators and automated systems verify that the correct dataset is being processed and that retention/disposition policies are observed.

Given Data / Assumptions:

• We consider standard operational labeling conventions.
• Trailer labels finalize and summarize the dataset written.
• Key metadata include the dataset (file) identifier and retention/disposition indicators.

Concept / Approach:
Trailer labels commonly store file identification and control data (for example, record counts, creation date, and retention information), enabling end-of-job verification and compliance with retention schedules. Including both identifiers and retention details facilitates audit trails and controlled media vaulting.

Step-by-Step Solution:
Identify the purpose of labels: accurate identification and lifecycle control.Confirm that file IDs and retention cues satisfy these purposes.Therefore, select “both (a) and (b).”

Verification / Alternative check:
Operations manuals describe trailer labels as containing dataset names and control information used by job control languages and tape management systems.

Why Other Options Are Wrong:

• File identification only: Incomplete; lacks retention guidance.
• Retention period only: Incomplete; without the file ID, controls are weakened.
• Neither / None: Incorrect because both are typically present.

Common Pitfalls:
Relying on handwritten or ad hoc labels; failing to synchronize label metadata with catalog systems.

Final Answer:
both (a) and (b)