diff --git a/interfaces/SimpleScene/SimpleScene.proto b/interfaces/SimpleScene/SimpleScene.proto
index 79aa262ba9416e19aec32aa3f097b9e0a15e98d5..39a89aa2b2f563e89b4c57e0195c3bf8905129c9 100644
--- a/interfaces/SimpleScene/SimpleScene.proto
+++ b/interfaces/SimpleScene/SimpleScene.proto
@@ -7,12 +7,12 @@ message IposConfigWrapper { // wrapper-message for configuration-topic
   repeated IposObject objects = 2; // an object must be either in this list
   repeated IposObjectConfig objectConfigs = 3; // or in this list, not in both
   repeated POI pois = 4;
-  repeated RefSystem refsystems = 5;
+  repeated RefSystem refSystems = 5;
   repeated IposMonitoringRequest monitoringRequests = 6;
 }
 
 message IposObjectConfig {
-  string id = 1; // unique for each object, but there may be multiple positioning sensors for that object
+  string agentId = 1; // unique for each object, but there may be multiple positioning sensors for that object
   string sensorId = 2; // unique (each sensor localizes a single object)
   string agentType = 3; // CeTI will send BOX,BIN,ZONE,ROBOT,HUMAN,OTHER
   string sensorType = 4; // BLUETOOTH, UWB, NFC, RFID, IMU...
@@ -21,6 +21,12 @@ message IposObjectConfig {
 
 message IposPositionEvent {
   repeated IposObject object = 1;
+  string type = 2; // deprecated may be ExitNotification or EntryNotification
+  // repeated IposZoneDescriptor zoneDescriptors = 2; // contains information about all zones that this position belongs to
+}
+
+message IposZoneDescriptor {
+  string zoneId = 1;
   string type = 2; // may be ExitNotification or EntryNotification
 }
 
@@ -36,17 +42,18 @@ message IposObject {
 
 message IposFrameConfig {
   string id = 1; // unique for every frame, used for relative coordinates
-  IposSpace space = 2; // cube defining the extension, might be (0,0,0)
-  IposPosition position = 3; // centre of the "frame" cube
+  repeated IposSpace space = 2; // cube defining the extension, might be (0,0,0)
 }
 
 message RefSystem {
   string id = 1;
   IposPosition position = 2; // position of origin of RefSystem. May be relative or absolute
+  IposSimpleOrientation orientation = 3;
 }
 
 message IposMonitoringRequest {
-  string frameId = 1;
+  string frameId = 1; // deprecated
+  // repeated string frameIds = 1;
   float delta = 2; // min. change in position to trigger a position update, setting delta and updateFrequency to -1 cancels the (existing) monitoring task
   float updateFrequency = 3; // defines how many times per second a PositionUpdateEvent is sent
   repeated string type = 4; // object-types to be observed; CeTI will send BOX,BIN,ZONE,ROBOT,HUMAN,OTHER
@@ -76,15 +83,18 @@ message IposPoint3D {
 }
 
 message POI { // point-of-interest
-  string description = 1; // e.g., "tag"
-  map<string, string> data = 2; // e.g., "id" -> tag-id; "type" -> "nfc"
-  IposPosition position = 3;
+  string id = 1; // e.g. "NFC_TAG_1"
+  string description = 2; // e.g., "tag"
+  map<string, string> data = 3; // e.g., "tag-id" -> "b315332984"; "type" -> "nfc"
+  IposPosition position = 4;
 }
 
 message IposSpace {
-  float x = 1; // size in x direction in m
-  float y = 2; // size in y direction in m
-  float z = 3; // size in z direction in m (height)
+  IposPosition position = 1; // centre of the "space"-cube
+  IposSimpleOrientation orientation = 2;
+  float x = 3; // size in x direction in m
+  float y = 4; // size in y direction in m
+  float z = 5; // size in z direction in m (height)
 }
 
 message IposSimpleOrientation {