Question 30
A wholesaler receives inventory changes from three partners; one partner occasionally resends batches, producing duplicate invoices. Which limitation must be considered before claiming the issue is fully resolved?
Explanation
Correct Answer
At-least-once messaging can still require consumer deduplication. This caution prevents extrapolating beyond the specific evidence or product boundary. An integration boundary needs explicit replay and data consistency behavior. The unresolved point should be tested using message IDs, duplicate event traces and partner retry behavior rather than assuming a working interface proves full compliance or resilience.
Incorrect Answers
At-least-once delivery guarantees each business effect happens only once. This limitation is framed as a blanket exception, but the case requires a different, narrower caution. The relevant boundary is that at-least-once messaging can still require consumer deduplication. An integration boundary needs explicit replay and data consistency behavior. Inspect message IDs, duplicate event traces and partner retry behavior.
Broker delivery guarantees that partner systems never resend valid messages. The proposed claim mistakes an incomplete signal or product feature for a universal guarantee. The relevant boundary is that at-least-once messaging can still require consumer deduplication. An integration boundary needs explicit replay and data consistency behavior. Inspect message IDs, duplicate event traces and partner retry behavior.
Exact-once transport guarantees external partner systems never repeat payloads. This claim exceeds the evidence and ignores an important risk or operational dependency. The relevant boundary is that at-least-once messaging can still require consumer deduplication. An integration boundary needs explicit replay and data consistency behavior. Inspect message IDs, duplicate event traces and partner retry behavior.