diff --git a/neutron_lib/exceptions/qos.py b/neutron_lib/exceptions/qos.py
index ee5fd1475..7b5bdb7c2 100644
--- a/neutron_lib/exceptions/qos.py
+++ b/neutron_lib/exceptions/qos.py
@@ -69,6 +69,11 @@ class QosRuleNotSupported(e.Conflict):
     message = _("Rule %(rule_type)s is not supported by port %(port_id)s")
 
 
+class QosRuleNotSupportedByNetwork(e.Conflict):
+    message = _("Rule %(rule_type)s is not supported "
+                "by network %(network_id)s")
+
+
 class QoSRuleParameterConflict(e.Conflict):
     message = _("Unable to add the rule with value %(rule_value)s to the "
                 "policy %(policy_id)s as the existing rule of type "
diff --git a/neutron_lib/services/qos/base.py b/neutron_lib/services/qos/base.py
index 574a6f99a..938e40351 100644
--- a/neutron_lib/services/qos/base.py
+++ b/neutron_lib/services/qos/base.py
@@ -109,6 +109,17 @@ class DriverBase(object):
         """
         return True
 
+    def validate_rule_for_network(self, context, rule, network_id):
+        """Return True/False for valid/invalid.
+
+        This is only meant to be used when a rule is compatible
+        with some networks but not with others (depending on
+        network properties).
+
+        Returns True by default for backwards compatibility.
+        """
+        return True
+
     def create_policy(self, context, policy):
         """Create policy invocation.