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+```mermaid
+---
+title: Establish session
+---
+
+sequenceDiagram
+    App->>+Cam: LanSearch
+    Cam->>-App: PunchPkt (SerialNo)
+    App-->>Cam: P2PReq?
+    App-->>Cam: LstReq?
+    App-->>Cam: P2PAlive?
+    App->>+Cam: P2PRdy
+    Cam->>-App: P2PRdy
+   
+   loop Every 400-500ms
+        Cam-->>+App: P2PAlive
+        App-->>-Cam: P2PAliveAck
+    end
+```