PPT Slide
For communication in real time we may conclude:
- If the maximum time delay J is common knowledge and a message j includes a note on the time t it was sent at then at t+J even without any confirmation j has become common knowledge.
- If there is no common knowledge on the maximum time delay then no common knowledge of j can be achieved even if j and J were known to both parties from the beginning because
- The sending of confirmations has no effect on common knowledge. It is a non-simultaneous run through the communication system.