diff --git a/moto/ds/models.py b/moto/ds/models.py
index 84199a350..8d706df7b 100644
--- a/moto/ds/models.py
+++ b/moto/ds/models.py
@@ -107,7 +107,7 @@ class Directory(BaseModel):  # pylint: disable=too-many-instance-attributes
         """
         ip_addrs = []
         for subnet in subnets:
-            ips = ipaddress.IPv4Network(subnet.cidr_block)
+            ips = ipaddress.ip_network(subnet.cidr_block)
             # Not sure if the following could occur, but if it does,
             # the situation will be ignored.
             if ips:
diff --git a/moto/ds/responses.py b/moto/ds/responses.py
index 34b22aa67..7c1139d70 100644
--- a/moto/ds/responses.py
+++ b/moto/ds/responses.py
@@ -23,7 +23,7 @@ class DirectoryServiceResponse(BaseResponse):
         description = self._get_param("Description")
         size = self._get_param("Size")
         connect_settings = self._get_param("ConnectSettings")
-        tags = self._get_param("Tags")
+        tags = self._get_param("Tags", [])
         directory_id = self.ds_backend.connect_directory(
             region=self.region,
             name=name,
@@ -44,7 +44,7 @@ class DirectoryServiceResponse(BaseResponse):
         description = self._get_param("Description")
         size = self._get_param("Size")
         vpc_settings = self._get_param("VpcSettings")
-        tags = self._get_param("Tags")
+        tags = self._get_param("Tags", [])
         directory_id = self.ds_backend.create_directory(
             region=self.region,
             name=name,
@@ -72,7 +72,7 @@ class DirectoryServiceResponse(BaseResponse):
         description = self._get_param("Description")
         vpc_settings = self._get_param("VpcSettings")
         edition = self._get_param("Edition")
-        tags = self._get_param("Tags")
+        tags = self._get_param("Tags", [])
         directory_id = self.ds_backend.create_microsoft_ad(
             region=self.region,
             name=name,