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Next: Robustness to Lost Messages Up: Communication Paradigm Previous: Robustness to Active Interference

Multiple Simultaneous Responses

The next challenge to meet is that of messages that require responses from several teammates. However, not all messages are of this type. For example, a message meaning ``where are you?'' requires a response, while ``look out behind you'' does not. Therefore it is first necessary for agents to classify messages in terms of whether or not they require responses as a function of the <message-type> field. Since the low-bandwidth channel prevents multiple simultaneous responses, the agents must also reason about the number of intended recipients as indicated by the <target> field. Taking these two factors into account, there are six types of messages:

tabular82

When hearing any message, the agent should update its internal beliefs of the other agent's status as indicated by the <time-stamped-team-strategy> field. However, only when the message is intended for it should it consider the content of the message. Then it should use the following algorithm in response to the message:

s_enumerate91

Then, if an internal behavior keeps decrementing communicate-delay as time passes, an external behavior can use the communication condition-action pair presented in Section 2: if (response-flag set and communicate-delay==0) then SAY(response). Players can also set the communicate-delay variable in the event that they need to send multiple messages to the same agent in a short time. This communication paradigm allows agents to continue real-time acting while reasoning about the appropriate time to communicate.



Peter Stone
Mon Nov 24 11:31:14 EST 1997