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doc/design/Seq.md

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+## QoS0 Publish Sequence 
+
+
+```
+title QoS0 Publish Sequence
+
+C1->PubSub: Publish QoS0
+PubSub-->S2: Dispatch QoS0
+S2-->C2: Deliver QoS0
+```
+
+## QoS1 Publish Sequence
+
+