diff --git a/packages/@azure/arm-iothub/lib/iotHubClientContext.ts b/packages/@azure/arm-iothub/lib/iotHubClientContext.ts
index 6809caeb616d..19669fd683fb 100644
--- a/packages/@azure/arm-iothub/lib/iotHubClientContext.ts
+++ b/packages/@azure/arm-iothub/lib/iotHubClientContext.ts
@@ -46,7 +46,7 @@ export class IotHubClientContext extends msRestAzure.AzureServiceClient {
     }
     super(credentials, options);
 
-    this.apiVersion = '2018-04-01';
+    this.apiVersion = '2018-12-01-preview';
     this.acceptLanguage = 'en-US';
     this.longRunningOperationRetryTimeout = 30;
     this.baseUri = options.baseUri || this.baseUri || "https://management.azure.com";
diff --git a/packages/@azure/arm-iothub/lib/models/certificatesMappers.ts b/packages/@azure/arm-iothub/lib/models/certificatesMappers.ts
index 063684f78e5f..06bd7fe28ea3 100644
--- a/packages/@azure/arm-iothub/lib/models/certificatesMappers.ts
+++ b/packages/@azure/arm-iothub/lib/models/certificatesMappers.ts
@@ -38,6 +38,7 @@ export {
   CloudToDeviceProperties,
   FeedbackProperties,
   OperationsMonitoringProperties,
+  IotHubPropertiesDeviceStreams,
   IotHubSkuInfo
 } from "../models/mappers";
 
diff --git a/packages/@azure/arm-iothub/lib/models/index.ts b/packages/@azure/arm-iothub/lib/models/index.ts
index 2f2cbd0a4b7f..a6daac9150ec 100644
--- a/packages/@azure/arm-iothub/lib/models/index.ts
+++ b/packages/@azure/arm-iothub/lib/models/index.ts
@@ -493,7 +493,7 @@ export interface RoutingStorageContainerProperties {
   maxChunkSizeInBytes?: number;
   /**
    * @member {string} [encoding] Encoding that is used to serialize messages to
-   * blobs. Supported values are 'avro' and 'avroDeflate'. Default value is
+   * blobs. Supported values are 'avro' and 'avrodeflate'. Default value is
    * 'avro'.
    */
   encoding?: string;
@@ -647,8 +647,8 @@ export interface RoutingProperties {
  */
 export interface StorageEndpointProperties {
   /**
-   * @member {string} [sasTtlAsIso8601] The period of time for which the SAS
-   * URI generated by IoT Hub for file upload is valid. See:
+   * @member {string} [sasTtlAsIso8601] The period of time for which the the
+   * SAS URI generated by IoT Hub for file upload is valid. See:
    * https://docs.microsoft.com/azure/iot-hub/iot-hub-devguide-file-upload#file-upload-notification-configuration-options.
    */
   sasTtlAsIso8601?: string;
@@ -759,6 +759,19 @@ export interface OperationsMonitoringProperties {
   events?: { [propertyName: string]: OperationMonitoringLevel };
 }
 
+/**
+ * @interface
+ * An interface representing IotHubPropertiesDeviceStreams.
+ * The device streams properties of iothub.
+ *
+ */
+export interface IotHubPropertiesDeviceStreams {
+  /**
+   * @member {string[]} [streamingEndpoints] List of Device Streams Endpoints.
+   */
+  streamingEndpoints?: string[];
+}
+
 /**
  * @interface
  * An interface representing IotHubProperties.
@@ -783,7 +796,7 @@ export interface IotHubProperties {
    */
   readonly provisioningState?: string;
   /**
-   * @member {string} [state] The hub state.
+   * @member {string} [state] Thehub state state.
    * **NOTE: This property will not be serialized. It can only be populated by
    * the server.**
    */
@@ -839,6 +852,11 @@ export interface IotHubProperties {
    * @member {OperationsMonitoringProperties} [operationsMonitoringProperties]
    */
   operationsMonitoringProperties?: OperationsMonitoringProperties;
+  /**
+   * @member {IotHubPropertiesDeviceStreams} [deviceStreams] The device streams
+   * properties of iothub.
+   */
+  deviceStreams?: IotHubPropertiesDeviceStreams;
   /**
    * @member {Capabilities} [features] The capabilities and features enabled
    * for the IoT hub. Possible values include: 'None', 'DeviceManagement'
@@ -957,6 +975,12 @@ export interface OperationDisplay {
    * the server.**
    */
   readonly operation?: string;
+  /**
+   * @member {string} [description] Description of the operation
+   * **NOTE: This property will not be serialized. It can only be populated by
+   * the server.**
+   */
+  readonly description?: string;
 }
 
 /**
@@ -1398,13 +1422,13 @@ export interface RoutingMessage {
  */
 export interface RoutingTwinProperties {
   /**
-   * @member {any} [desiredProperties] Twin desired properties
+   * @member {any} [desired] Twin desired properties
    */
-  desiredProperties?: any;
+  desired?: any;
   /**
-   * @member {any} [reportedProperties] Twin desired properties
+   * @member {any} [reported] Twin desired properties
    */
-  reportedProperties?: any;
+  reported?: any;
 }
 
 /**
diff --git a/packages/@azure/arm-iothub/lib/models/iotHubResourceMappers.ts b/packages/@azure/arm-iothub/lib/models/iotHubResourceMappers.ts
index edcf42a6f5d8..c8a209fa4571 100644
--- a/packages/@azure/arm-iothub/lib/models/iotHubResourceMappers.ts
+++ b/packages/@azure/arm-iothub/lib/models/iotHubResourceMappers.ts
@@ -29,6 +29,7 @@ export {
   CloudToDeviceProperties,
   FeedbackProperties,
   OperationsMonitoringProperties,
+  IotHubPropertiesDeviceStreams,
   IotHubSkuInfo,
   ErrorDetails,
   TagsResource,
diff --git a/packages/@azure/arm-iothub/lib/models/mappers.ts b/packages/@azure/arm-iothub/lib/models/mappers.ts
index a4484a54dd40..887107cbbc17 100644
--- a/packages/@azure/arm-iothub/lib/models/mappers.ts
+++ b/packages/@azure/arm-iothub/lib/models/mappers.ts
@@ -965,6 +965,27 @@ export const OperationsMonitoringProperties: msRest.CompositeMapper = {
   }
 };
 
+export const IotHubPropertiesDeviceStreams: msRest.CompositeMapper = {
+  serializedName: "IotHubProperties_deviceStreams",
+  type: {
+    name: "Composite",
+    className: "IotHubPropertiesDeviceStreams",
+    modelProperties: {
+      streamingEndpoints: {
+        serializedName: "streamingEndpoints",
+        type: {
+          name: "Sequence",
+          element: {
+            type: {
+              name: "String"
+            }
+          }
+        }
+      }
+    }
+  }
+};
+
 export const IotHubProperties: msRest.CompositeMapper = {
   serializedName: "IotHubProperties",
   type: {
@@ -1085,6 +1106,13 @@ export const IotHubProperties: msRest.CompositeMapper = {
           className: "OperationsMonitoringProperties"
         }
       },
+      deviceStreams: {
+        serializedName: "deviceStreams",
+        type: {
+          name: "Composite",
+          className: "IotHubPropertiesDeviceStreams"
+        }
+      },
       features: {
         serializedName: "features",
         type: {
@@ -1240,6 +1268,13 @@ export const OperationDisplay: msRest.CompositeMapper = {
         type: {
           name: "String"
         }
+      },
+      description: {
+        readOnly: true,
+        serializedName: "description",
+        type: {
+          name: "String"
+        }
       }
     }
   }
@@ -1808,14 +1843,14 @@ export const RoutingTwinProperties: msRest.CompositeMapper = {
     name: "Composite",
     className: "RoutingTwinProperties",
     modelProperties: {
-      desiredProperties: {
-        serializedName: "desiredProperties",
+      desired: {
+        serializedName: "desired",
         type: {
           name: "Object"
         }
       },
-      reportedProperties: {
-        serializedName: "reportedProperties",
+      reported: {
+        serializedName: "reported",
         type: {
           name: "Object"
         }