دلالات التسليم

في هذا الدرس

explain the three guarantees and the exactly-once limit.

الموضوعات المخطط لها

• At-most-once: send and forget; messages may be lost, never duplicated.
• At-least-once: retry until acknowledged; no loss, but duplicates are possible. The usual default.
• Exactly-once delivery across systems is not achievable end to end, because an acknowledgment can be lost (MID-023).
• Effectively-once: at-least-once delivery plus idempotent processing (or deduplication), so repeats have no extra effect.
• Some platforms offer exactly-once processing within their own boundary (for example Kafka transactions); verify scope before relying on it.