messaging - Publish/Subscribe pattern with subscriber response -


is possible in publish/subscribe pattern?

  1. a publisher publishes message topic;
  2. subscriber(s) receive(s) message;
  3. the subscribers reply publisher custom message.

is step 3 possible? i'm designing system use mqtt protocol (communication between smartphones , microcontrollers). however, subscriber needs send answer publisher other acknowledged message.

there no way directly reply message in mqtt system, there nothing stop using 2 topics (outboud/inbound) , including message id in payload of message identify reply original published message


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