diff --git a/specification/datafactory/resource-manager/Microsoft.DataFactory/2017-09-01-preview/entityTypes/Trigger.json b/specification/datafactory/resource-manager/Microsoft.DataFactory/2017-09-01-preview/entityTypes/Trigger.json
index e428ab333549..8d3e7cea460e 100644
--- a/specification/datafactory/resource-manager/Microsoft.DataFactory/2017-09-01-preview/entityTypes/Trigger.json
+++ b/specification/datafactory/resource-manager/Microsoft.DataFactory/2017-09-01-preview/entityTypes/Trigger.json
@@ -18,13 +18,6 @@
           "description": "Trigger description.",
           "type": "string"
         },
-        "pipelines": {
-          "type": "array",
-          "items": {
-            "$ref": "../datafactory.json#/definitions/TriggerPipelineReference"
-          },
-          "description": "Pipelines that need to be started."
-        },
         "runtimeState": {
           "$ref": "#/definitions/TriggerRuntimeState",
           "description": "Indicates if trigger is running or not. Updated when Start/Stop APIs are called on the Trigger.",
@@ -48,12 +41,30 @@
         "modelAsString": true
       }
     },
+    "MultiplePipelineTrigger": {
+      "x-ms-discriminator-value": "MultiplePipelineTrigger",
+      "description": "Base class for all triggers that support one to many model for trigger to pipeline.",
+      "allOf": [
+        {
+          "$ref": "#/definitions/Trigger"
+        }
+      ],
+      "properties": {
+        "pipelines": {
+          "type": "array",
+          "items": {
+            "$ref": "../datafactory.json#/definitions/TriggerPipelineReference"
+          },
+          "description": "Pipelines that need to be started."
+        }
+      }
+    },
     "ScheduleTrigger": {
       "description": "Trigger that creates pipeline runs periodically, on schedule.",
       "type": "object",
       "allOf": [
         {
-          "$ref": "#/definitions/Trigger"
+          "$ref": "#/definitions/MultiplePipelineTrigger"
         }
       ],
       "properties": {
@@ -219,7 +230,7 @@
       "type": "object",
       "allOf": [
         {
-          "$ref": "#/definitions/Trigger"
+          "$ref": "#/definitions/MultiplePipelineTrigger"
         }
       ],
       "properties": {
@@ -250,6 +261,97 @@
       "required": [
         "typeProperties"
       ]
+    },
+    "TumblingWindowTrigger": {
+      "description": "Trigger that schedules pipeline runs for all fixed time interval windows from a start time without gaps and also supports backfill scenarios (when start time is in the past).",
+      "type": "object",
+      "allOf": [
+        {
+          "$ref": "#/definitions/Trigger"
+        }
+      ],
+      "properties": {
+        "pipeline": {
+          "$ref": "../datafactory.json#/definitions/TriggerPipelineReference",
+          "description": "Pipeline for which runs are created when an event is fired for trigger window that is ready."
+        },
+        "typeProperties": {
+          "description": "Tumbling Window Trigger properties.",
+          "x-ms-client-flatten": true,
+          "properties": {
+            "frequency": {
+              "$ref": "#/definitions/TumblingWindowFrequency", 
+              "description": "The frequency of the time windows."
+            },
+            "interval": {
+              "type": "integer",
+              "format": "int32",
+              "description": "The interval of the time windows. The minimum interval allowed is 15 Minutes."
+            },
+            "startTime": {
+              "type": "string",
+              "format": "date-time",
+              "description": "The start time for the time period for the trigger during which events are fired for windows that are ready. Only UTC time is currently supported."
+            },
+            "endTime": {
+              "type": "string",
+              "format": "date-time",
+              "description": "The end time for the time period for the trigger during which events are fired for windows that are ready. Only UTC time is currently supported."
+            },
+            "delay": {
+              "type": "object",
+              "description": "Specifies how long the trigger waits past due time before triggering new run. It doesn't alter window start and end time. The default is 0. Type: string (or Expression with resultType string), pattern: ((\\d+)\\.)?(\\d\\d):(60|([0-5][0-9])):(60|([0-5][0-9]))."
+            },
+            "maxConcurrency": {
+              "description": "The max number of parallel time windows (ready for execution) for which a new run is triggered.",
+              "type": "integer",
+              "minimum": 1,
+              "maximum": 50
+            },
+            "retryPolicy": {
+              "$ref": "#/definitions/RetryPolicy",
+              "description": "Retry policy that will be applied for failed pipeline runs."
+            }
+          },
+          "required": [
+            "frequency",
+            "interval",
+            "startTime",
+            "maxConcurrency"
+          ]
+        }
+      },
+      "required": [
+        "pipeline",
+        "typeProperties"
+      ]
+    },
+    "TumblingWindowFrequency": {
+      "description": "Enumerates possible frequency option for the tumbling window trigger.",
+      "type": "string",
+      "enum": [
+        "Minute",
+        "Hour"
+      ],
+      "x-ms-enum": {
+        "name": "TumblingWindowFrequency",
+        "modelAsString": true
+      }
+    },
+    "RetryPolicy": {
+      "description": "Execution policy for an activity.",
+      "properties": {
+        "count": {
+          "type": "object",
+          "description": "Maximum ordinary retry attempts. Default is 0. Type: integer (or Expression with resultType integer), minimum: 0."
+        },
+        "intervalInSeconds": {
+          "description": "Interval between retries in seconds. Default is 30.",
+          "type": "integer",
+          "minimum": 30,
+          "maximum": 86400
+        }
+      }
     }
   }
 }