diff --git a/xos/synchronizer/manifest b/xos/synchronizer/manifest
new file mode 100644
index 0000000..dccfcdc
--- /dev/null
+++ b/xos/synchronizer/manifest
@@ -0,0 +1,10 @@
+manifest
+vtn-synchronizer.py
+steps/sync_tenant.py
+steps/sync_port_addresses.py
+start.sh
+stop.sh
+model-deps
+supervisor/vtn-observer.conf
+run.sh
+vtn_synchronizer_config
diff --git a/xos/synchronizer/model-deps b/xos/synchronizer/model-deps
new file mode 100644
index 0000000..0967ef4
--- /dev/null
+++ b/xos/synchronizer/model-deps
@@ -0,0 +1 @@
+{}
diff --git a/xos/synchronizer/run.sh b/xos/synchronizer/run.sh
new file mode 100755
index 0000000..000a563
--- /dev/null
+++ b/xos/synchronizer/run.sh
@@ -0,0 +1,2 @@
+export XOS_DIR=/opt/xos
+python vtn-synchronizer.py  -C $XOS_DIR/synchronizers/vtn/vtn_synchronizer_config
diff --git a/xos/synchronizer/start.sh b/xos/synchronizer/start.sh
new file mode 100755
index 0000000..2c43440
--- /dev/null
+++ b/xos/synchronizer/start.sh
@@ -0,0 +1,2 @@
+export XOS_DIR=/opt/xos
+nohup python vtn-synchronizer.py  -C $XOS_DIR/synchronizers/vtn/vtn_synchronizer_config > /dev/null 2>&1 &
diff --git a/xos/synchronizer/steps/sync_port_addresses.py b/xos/synchronizer/steps/sync_port_addresses.py
new file mode 100644
index 0000000..553df6f
--- /dev/null
+++ b/xos/synchronizer/steps/sync_port_addresses.py
@@ -0,0 +1,133 @@
+import os
+import requests
+import socket
+import sys
+import base64
+from django.db.models import F, Q
+from xos.config import Config
+from synchronizers.base.syncstep import SyncStep
+from core.models import Service, Port, Controller, Tag, Tenant
+from core.models.service import COARSE_KIND
+from services.vsg.models import VSGTenant
+from xos.logger import Logger, logging
+from requests.auth import HTTPBasicAuth
+
+# hpclibrary will be in steps/..
+parentdir = os.path.join(os.path.dirname(__file__),"..")
+sys.path.insert(0,parentdir)
+
+logger = Logger(level=logging.INFO)
+
+# XXX should save and load this
+glo_saved_vtn_maps = []
+
+class SyncPortAddresses(SyncStep):
+    requested_interval = 0 # 3600
+    provides=[Port]
+    observes=Port
+
+    def __init__(self, **args):
+        SyncStep.__init__(self, **args)
+
+    def call(self, **args):
+        global glo_saved_vtn_maps
+
+        logger.info("sync'ing vsg tenant to port addresses")
+
+        # build up a dictionary of port-->[wan_addrs] mappings
+        port_addrs = {}
+        for vsg in VSGTenant.get_tenant_objects().all():
+            if not vsg.instance:
+                logger.info("skipping vsg %s because it has no instance" % vsg)
+
+            wan_ip = vsg.wan_container_ip
+            if not wan_ip:
+                logger.info("skipping vsg %s because it has no wan_container_ip" % vsg)
+
+            wan_mac = vsg.wan_container_mac
+            if not wan_mac:
+                logger.info("skipping vsg %s because it has no wan_container_mac" % vsg)
+
+            lan_network = vsg.get_lan_network(vsg.instance)
+            if not lan_network:
+                logger.info("skipping vsg %s because it has no lan_network" % vsg)
+
+            lan_port = Port.objects.filter(instance = vsg.instance, network=lan_network)
+            if not lan_port:
+                logger.info("skipping vsg %s because it has no lan_port" % vsg)
+            lan_port = lan_port[0]
+
+            if not lan_port.port_id:
+                logger.info("skipping vsg %s because its lan_port has no port_id" % vsg)
+
+            if not (lan_port.pk in port_addrs):
+                port_addrs[lan_port.pk] = []
+            entry = {"mac_address": wan_mac, "ip_address": wan_ip}
+            addr_pairs = port_addrs[lan_port.pk]
+            if not entry in addr_pairs:
+                 addr_pairs.append(entry)
+
+            # now do the VM_WAN_IP from the instance
+            if vsg.instance:
+                wan_vm_ip = vsg.wan_vm_ip
+                wan_vm_mac = vsg.wan_vm_mac
+                entry = {"mac_address": wan_vm_mac, "ip_address": wan_vm_ip}
+                if not entry in addr_pairs:
+                    addr_pairs.append(entry)
+
+        # Get all ports in all controllers
+        ports_by_id = {}
+        for controller in Controller.objects.all():
+            if not controller.admin_tenant:
+                logger.info("controller %s has no admin_tenant" % controller)
+                continue
+            try:
+                driver = self.driver.admin_driver(controller = controller)
+                ports = driver.shell.quantum.list_ports()["ports"]
+            except:
+                logger.log_exc("failed to get ports from controller %s" % controller)
+                continue
+
+            for port in ports:
+                ports_by_id[port["id"]] = port
+
+        for port_pk in port_addrs.keys():
+            port = Port.objects.get(pk=port_pk)
+            addr_pairs = port_addrs[port_pk]
+            neutron_port = ports_by_id.get(port.port_id,None)
+            if not neutron_port:
+                logger.info("failed to get neutron port for port %s" % port)
+                continue
+
+            ips = [x["ip_address"] for x in addr_pairs]
+
+            changed = False
+
+            # delete addresses in neutron that don't exist in XOS
+            aaps = neutron_port.get("allowed_address_pairs", [])
+            for aap in aaps[:]:
+                if not aap["ip_address"] in ips:
+                    logger.info("removing address %s from port %s" % (aap["ip_address"], port))
+                    aaps.remove(aap)
+                    changed = True
+
+            aaps_ips = [x["ip_address"] for x in aaps]
+
+            # add addresses in XOS that don't exist in neutron
+            for addr in addr_pairs:
+                if not addr["ip_address"] in aaps_ips:
+                    logger.info("adding address %s to port %s" % (addr, port))
+                    aaps.append( addr )
+                    aaps_ips.append(addr["ip_address"])
+                    changed = True
+
+            if changed:
+                logger.info("updating port %s" % port)
+                driver.shell.quantum.update_port(port.port_id, {"port": {"allowed_address_pairs": aaps}})
+
+
+
+
+
+
+
diff --git a/xos/synchronizer/steps/sync_tenant.py b/xos/synchronizer/steps/sync_tenant.py
new file mode 100644
index 0000000..a0e6cdb
--- /dev/null
+++ b/xos/synchronizer/steps/sync_tenant.py
@@ -0,0 +1,94 @@
+import os
+import requests
+import socket
+import sys
+import base64
+from django.db.models import F, Q
+from xos.config import Config
+from synchronizers.base.syncstep import SyncStep
+from core.models import Service, Tenant
+from core.models.service import COARSE_KIND
+from xos.logger import Logger, logging
+from requests.auth import HTTPBasicAuth
+
+# hpclibrary will be in steps/..
+parentdir = os.path.join(os.path.dirname(__file__),"..")
+sys.path.insert(0,parentdir)
+
+logger = Logger(level=logging.INFO)
+
+# XXX should save and load this
+glo_saved_vtn_maps = []
+
+class SyncTenant(SyncStep):
+    provides=[Tenant]
+    observes=Tenant
+    requested_interval=0
+
+    def __init__(self, **args):
+        SyncStep.__init__(self, **args)
+
+    def get_vtn_onos_service(self):
+#        vtn_tenant = Tenant.objects.filter(name="VTN_ONOS_app")   # XXX fixme - hardcoded
+#        if not vtn_tenant:
+#            raise "No VTN Onos App found"
+#        vtn_tenant = vtn_tenant[0]
+#
+#        vtn_service = vtn_tenant.provider_service
+        vtn_service = Service.objects.filter(name="service_ONOS_VTN")  # XXX fixme - harcoded
+        if not vtn_service:
+            raise "No VTN Onos Service"
+
+        return vtn_service[0]
+
+    def get_vtn_addr(self):
+        vtn_service = self.get_vtn_onos_service()
+
+        if not vtn_service.slices.exists():
+            raise "VTN Service has no slices"
+
+        vtn_slice = vtn_service.slices.all()[0]
+
+        if not vtn_slice.instances.exists():
+            raise "VTN Slice has no instances"
+
+        vtn_instance = vtn_slice.instances.all()[0]
+
+        return vtn_instance.node.name
+
+    def call(self, **args):
+        global glo_saved_vtn_maps
+
+        logger.info("sync'ing vtn services")
+
+        vtn_maps = []
+        for service in Service.objects.all():
+           for id in service.get_vtn_src_ids():
+               dependencies = service.get_vtn_dependencies_ids()
+               if dependencies:
+                   for dependency in dependencies:
+                       vtn_maps.append( (id, dependency) )
+
+        for vtn_map in vtn_maps:
+            if not (vtn_map in glo_saved_vtn_maps):
+                # call vtn rest api to add map
+                url = "http://" + self.get_vtn_addr() + ":8181/onos/cordvtn/service-dependency/%s/%s" % (vtn_map[0], vtn_map[1])
+
+                print "POST %s" % url
+                r = requests.post(url, auth=HTTPBasicAuth('karaf', 'karaf') )    # XXX fixme - hardcoded auth
+                if (r.status_code != 200):
+                    raise Exception("Received error from vtn service (%d)" % r.status_code)
+
+        for vtn_map in glo_saved_vtn_maps:
+            if not vtn_map in vtn_maps:
+                # call vtn rest api to delete map
+                url = "http://" + self.get_vtn_addr() + ":8181/onos/cordvtn/service-dependency/%s/%s" % (vtn_map[0],vtn_map[1])
+
+                print "DELETE %s" % url
+                r = requests.delete(url, auth=HTTPBasicAuth('karaf', 'karaf') )    # XXX fixme - hardcoded auth
+                if (r.status_code != 200):
+                    raise Exception("Received error from vtn service (%d)" % r.status_code)
+
+        glo_saved_vtn_maps = vtn_maps
+        # TODO: save this
+
diff --git a/xos/synchronizer/stop.sh b/xos/synchronizer/stop.sh
new file mode 100755
index 0000000..7ff2b06
--- /dev/null
+++ b/xos/synchronizer/stop.sh
@@ -0,0 +1 @@
+pkill -9 -f vtn-synchronizer.py
diff --git a/xos/synchronizer/supervisor/vtn-observer.conf b/xos/synchronizer/supervisor/vtn-observer.conf
new file mode 100644
index 0000000..714afa7
--- /dev/null
+++ b/xos/synchronizer/supervisor/vtn-observer.conf
@@ -0,0 +1,2 @@
+[program:vtn-observer]
+command=python /opt/xos/observers/vbng/vtn-observer.py -C /opt/xos/observers/vbng/vtn_observer_config
diff --git a/xos/synchronizer/vtn-synchronizer.py b/xos/synchronizer/vtn-synchronizer.py
new file mode 100755
index 0000000..84bec4f
--- /dev/null
+++ b/xos/synchronizer/vtn-synchronizer.py
@@ -0,0 +1,11 @@
+#!/usr/bin/env python
+
+# This imports and runs ../../xos-observer.py
+
+import importlib
+import os
+import sys
+observer_path = os.path.join(os.path.dirname(os.path.realpath(__file__)),"../../synchronizers/base")
+sys.path.append(observer_path)
+mod = importlib.import_module("xos-synchronizer")
+mod.main()
diff --git a/xos/synchronizer/vtn_synchronizer_config b/xos/synchronizer/vtn_synchronizer_config
new file mode 100644
index 0000000..d931839
--- /dev/null
+++ b/xos/synchronizer/vtn_synchronizer_config
@@ -0,0 +1,44 @@
+
+[plc]
+name=plc
+deployment=VICCI
+
+[db]
+name=xos
+user=postgres
+password=password
+host=localhost
+port=5432
+
+[api]
+host=128.112.171.237
+port=8000
+ssl_key=None
+ssl_cert=None
+ca_ssl_cert=None
+ratelimit_enabled=0
+omf_enabled=0
+mail_support_address=support@localhost
+nova_enabled=True
+
+[observer]
+name=vtn
+dependency_graph=/opt/xos/synchronizers/vtn/model-deps
+steps_dir=/opt/xos/synchronizers/vtn/steps
+sys_dir=/opt/xos/synchronizers/vtn/sys
+deleters_dir=/opt/xos/synchronizers/vtn/deleters
+log_file=console
+#/var/log/hpc.log
+driver=openstack
+pretend=False
+backoff_disabled=True
+
+[nova]
+ca_ssl_cert=/etc/ssl/certs/ca-certificates.crt
+
+[feefie]
+client_id='vicci_dev_central'
+user_id='pl'
+
+[networking]
+use_vtn=True