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+# c2 - Command and control #
+
+## mqtts ca certificates ##
+
+- combine root authority certificate and intermediary certificates into one `.pem` file
+`cat rootcert.pem intermediarycert.pem > cacert.pem`
+
+## mqtt topic structure ##
+
+`<major scope>/<minor scope>/<type of device>/<device>/<specific topic>`