diff --git a/tempest/common/utils/net_utils.py b/tempest/common/utils/net_utils.py
new file mode 100644
index 0000000..d98fb32
--- /dev/null
+++ b/tempest/common/utils/net_utils.py
@@ -0,0 +1,48 @@
+# Copyright 2016 Hewlett Packard Enterprise Development Company
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import itertools
+import netaddr
+
+from tempest.lib import exceptions as lib_exc
+
+
+def get_unused_ip_addresses(ports_client, subnets_client,
+                            network_id, subnet_id, count):
+
+    """Return a list with the specified number of unused IP addresses
+
+    This method uses the given ports_client to find the specified number of
+    unused IP addresses on the given subnet using the supplied subnets_client
+    """
+
+    ports = ports_client.list_ports(network_id=network_id)['ports']
+    subnet = subnets_client.show_subnet(subnet_id)
+    ip_net = netaddr.IPNetwork(subnet['subnet']['cidr'])
+    subnet_set = netaddr.IPSet(ip_net.iter_hosts())
+    alloc_set = netaddr.IPSet()
+
+    # prune out any addresses already allocated to existing ports
+    for port in ports:
+        for fixed_ip in port.get('fixed_ips'):
+            alloc_set.add(fixed_ip['ip_address'])
+
+    av_set = subnet_set - alloc_set
+    ip_list = [str(ip) for ip in itertools.islice(av_set, count)]
+
+    if len(ip_list) != count:
+        msg = "Insufficient IP addresses available"
+        raise lib_exc.BadRequest(message=msg)
+
+    return ip_list