diff --git a/JSON_for_IO-Link_unmerged.yaml b/JSON_for_IO-Link_unmerged.yaml
index 93b4fb7..5d0847c 100644
--- a/JSON_for_IO-Link_unmerged.yaml
+++ b/JSON_for_IO-Link_unmerged.yaml
@@ -4282,7 +4282,8 @@ components:
       description: |
         Parameter identifier. Can be either the parameter index (integer) or the parameter name (string). \
         Access via parameter names requires IODD support. \
-        Parameter names come from the IODD but are reformatted according to the **Parameter naming rules** described in the general remarks section above.
+        Parameter names come from the IODD but are reformatted according to the **Parameter naming rules** described in the general remarks section above. \
+        The index is an integer in the range of 0 to 65535.
       required: true
       schema:
         $ref: "./schemas.yaml#/schemas/parameterIdent"
diff --git a/schemas.yaml b/schemas.yaml
index 22928a4..bd03348 100644
--- a/schemas.yaml
+++ b/schemas.yaml
@@ -3394,13 +3394,9 @@ schemas:
         portNumber: 4
         ioddFileName: vendorname-devicename-20231016-IODD1.1.xml
   parameterIdent:
-    oneOf:
-      - $ref: "#/schemas/parameterName"
-      - $ref: "#/schemas/index"
+    $ref: "#/schemas/parameterName"
   subParameterIdent:
-    oneOf:
-      - $ref: "#/schemas/subParameterName"
-      - $ref: "#/schemas/subIndex"
+    $ref: "#/schemas/subParameterName"
   rawSmi:
     type: object
     properties: