--- a/service/iot2/messages.capnp	Wed Jan 29 01:02:06 2020 -0800
+++ b/service/iot2/messages.capnp	Wed Jan 29 01:03:40 2020 -0800
@@ -6,3 +6,27 @@
   sensor @0 :Data;
   value @1 :Float32;
 }
+
+# node is at config version n (config pusher will update it)
+# replace node config
+# node component returns interesting sensor reports
+# node component periodically returns state
+# send 'command' updates to components
+
+# from node: <node>/announce
+# (<node> is picked by the node itself, often hostname or an id compiled into esp code)
+struct NodeAnnounce {
+  config_version @0 :Int32;
+  hostname @1 :Data;
+  mac_address @2 :UInt64; # 48-bit
+}
+
+# to node: <node>/configure
+struct ConfigureNode {
+  config_version @0 :Int32;
+  components @0 :List(Component)
+  struct Component {
+    id :Text
+
+  }
+}