diff --git a/neutron/services/trunk/rules.py b/neutron/services/trunk/rules.py
index 80fb80cee31..9535e9f1ed7 100644
--- a/neutron/services/trunk/rules.py
+++ b/neutron/services/trunk/rules.py
@@ -12,6 +12,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from neutron_lib.api import converters
 from neutron_lib import constants as n_const
 from neutron_lib import exceptions as n_exc
 
@@ -102,20 +103,26 @@ class SubPortsValidator(object):
         # figure out defaults when the time comes to support Ironic.
         # We can reasonably expect segmentation details to be provided
         # in all other cases for now.
-        segmentation_id = subport.get("segmentation_id")
-        segmentation_type = subport.get("segmentation_type")
-        if not segmentation_id or not segmentation_type:
+        try:
+            segmentation_type = subport["segmentation_type"]
+            segmentation_id = (
+                converters.convert_to_int(subport["segmentation_id"]))
+        except KeyError:
             msg = _("Invalid subport details '%s': missing segmentation "
                     "information. Must specify both segmentation_id and "
                     "segmentation_type") % subport
             raise n_exc.InvalidInput(error_message=msg)
+        except n_exc.InvalidInput:
+            msg = _("Invalid subport details: segmentation_id '%s' is "
+                    "not an integer") % subport["segmentation_id"]
+            raise n_exc.InvalidInput(error_message=msg)
 
         if segmentation_type not in self._segmentation_types:
-            msg = _("Invalid segmentation_type '%s'") % segmentation_type
+            msg = _("Unknown segmentation_type '%s'") % segmentation_type
             raise n_exc.InvalidInput(error_message=msg)
 
         if not self._segmentation_types[segmentation_type](segmentation_id):
-            msg = _("Invalid segmentation id '%s'") % segmentation_id
+            msg = _("Segmentation ID '%s' is not in range") % segmentation_id
             raise n_exc.InvalidInput(error_message=msg)
 
         trunk_validator = TrunkPortValidator(subport['port_id'])
diff --git a/neutron/services/trunk/validators/vlan.py b/neutron/services/trunk/validators/vlan.py
index 51f61abfa3f..a9ef8f89570 100644
--- a/neutron/services/trunk/validators/vlan.py
+++ b/neutron/services/trunk/validators/vlan.py
@@ -16,7 +16,7 @@ from oslo_log import log as logging
 
 from neutron.callbacks import events
 from neutron.callbacks import registry
-from neutron.plugins.common import constants as common_consts
+from neutron.plugins.common import utils
 from neutron.services.trunk import constants as trunk_consts
 
 LOG = logging.getLogger(__name__)
@@ -29,10 +29,6 @@ def register():
 
 
 def handler(resource, event, trigger, **kwargs):
-    trigger.add_segmentation_type(trunk_consts.VLAN, vlan_range)
+    trigger.add_segmentation_type(
+        trunk_consts.VLAN, utils.is_valid_vlan_tag)
     LOG.debug('Registration complete')
-
-
-def vlan_range(segmentation_id):
-    min_vid, max_vid = common_consts.MIN_VLAN_TAG, common_consts.MAX_VLAN_TAG
-    return min_vid <= segmentation_id <= max_vid
diff --git a/neutron/tests/unit/services/trunk/test_rules.py b/neutron/tests/unit/services/trunk/test_rules.py
index ba205c691ee..6de285d4d43 100644
--- a/neutron/tests/unit/services/trunk/test_rules.py
+++ b/neutron/tests/unit/services/trunk/test_rules.py
@@ -20,11 +20,11 @@ from neutron_lib import exceptions as n_exc
 from oslo_utils import uuidutils
 
 from neutron import manager
+from neutron.plugins.common import utils
 from neutron.services.trunk import constants
 from neutron.services.trunk import exceptions as trunk_exc
 from neutron.services.trunk import plugin as trunk_plugin
 from neutron.services.trunk import rules
-from neutron.services.trunk.validators import vlan as vlan_driver
 from neutron.tests import base
 from neutron.tests.unit.plugins.ml2 import test_plugin
 
@@ -33,7 +33,7 @@ class SubPortsValidatorTestCase(base.BaseTestCase):
 
     def setUp(self):
         super(SubPortsValidatorTestCase, self).setUp()
-        self.segmentation_types = {constants.VLAN: vlan_driver.vlan_range}
+        self.segmentation_types = {constants.VLAN: utils.is_valid_vlan_tag}
         self.context = mock.ANY
 
     def test_validate_subport_subport_and_trunk_shared_port_id(self):
@@ -57,6 +57,26 @@ class SubPortsValidatorTestCase(base.BaseTestCase):
                           validator.validate,
                           self.context)
 
+    def test_validate_subport_vlan_id_not_an_int(self):
+        validator = rules.SubPortsValidator(
+            self.segmentation_types,
+            [{'port_id': uuidutils.generate_uuid(),
+              'segmentation_type': 'vlan',
+              'segmentation_id': 'IamNotAnumber'}])
+        self.assertRaises(n_exc.InvalidInput,
+                          validator.validate,
+                          self.context)
+
+    def test_validate_subport_valid_vlan_id_as_string(self):
+        validator = rules.SubPortsValidator(
+            self.segmentation_types,
+            [{'port_id': uuidutils.generate_uuid(),
+              'segmentation_type': 'vlan',
+              'segmentation_id': '2'}])
+        with mock.patch.object(rules.TrunkPortValidator, 'validate') as f:
+            validator.validate(self.context)
+            f.assert_called_once_with(self.context)
+
     def test_validate_subport_subport_invalid_segmenation_type(self):
         validator = rules.SubPortsValidator(
             self.segmentation_types,
@@ -101,7 +121,7 @@ class TrunkPortValidatorTestCase(test_plugin.Ml2PluginV2TestCase):
         super(TrunkPortValidatorTestCase, self).setUp()
         self.trunk_plugin = trunk_plugin.TrunkPlugin()
         self.trunk_plugin.add_segmentation_type(constants.VLAN,
-                                                vlan_driver.vlan_range)
+                                                utils.is_valid_vlan_tag)
 
     def test_validate_port_parent_in_use_by_trunk(self):
         with self.port() as trunk_parent: