migrate vrouter service from XOS repo:
diff --git a/xos/models.py b/xos/models.py
new file mode 100644
index 0000000..d302b13
--- /dev/null
+++ b/xos/models.py
@@ -0,0 +1,143 @@
+from django.db import models
+from core.models import Service, PlCoreBase, Slice, Instance, Tenant, TenantWithContainer, Node, Image, User, Flavor, Subscriber, NetworkParameter, NetworkParameterType, Port, AddressPool
+from core.models.plcorebase import StrippedCharField
+import os
+from django.db import models, transaction
+from django.forms.models import model_to_dict
+from django.db.models import Q
+from operator import itemgetter, attrgetter, methodcaller
+from core.models import Tag
+from core.models.service import LeastLoadedNodeScheduler
+import traceback
+from xos.exceptions import *
+from xos.config import Config
+
+class ConfigurationError(Exception):
+    pass
+
+
+VROUTER_KIND = "vROUTER"
+
+# NOTE: don't change VROUTER_KIND unless you also change the reference to it
+#   in tosca/resources/network.py
+
+CORD_USE_VTN = getattr(Config(), "networking_use_vtn", False)
+
+class VRouterService(Service):
+    KIND = VROUTER_KIND
+
+    class Meta:
+        app_label = "vrouter"
+        verbose_name = "vRouter Service"
+        proxy = True
+
+    def ip_to_mac(self, ip):
+        (a, b, c, d) = ip.split('.')
+        return "02:42:%02x:%02x:%02x:%02x" % (int(a), int(b), int(c), int(d))
+
+    def get_gateways(self):
+        gateways=[]
+
+        aps = self.addresspools.all()
+        for ap in aps:
+            gateways.append( {"gateway_ip": ap.gateway_ip, "gateway_mac": ap.gateway_mac} )
+
+        return gateways
+
+    def get_address_pool(self, name):
+        ap = AddressPool.objects.filter(name=name, service=self)
+        if not ap:
+            raise Exception("vRouter unable to find addresspool %s" % name)
+        return ap[0]
+
+    def get_tenant(self, **kwargs):
+        address_pool_name = kwargs.pop("address_pool_name")
+
+        ap = self.get_address_pool(address_pool_name)
+
+        ip = ap.get_address()
+        if not ip:
+            raise Exception("AddressPool '%s' has run out of addresses." % ap.name)
+
+        t = VRouterTenant(provider_service=self, **kwargs)
+        t.public_ip = ip
+        t.public_mac = self.ip_to_mac(ip)
+        t.address_pool_id = ap.id
+        t.save()
+
+        return t
+
+#VRouterService.setup_simple_attributes()
+
+class VRouterTenant(Tenant):
+    class Meta:
+        proxy = True
+
+    KIND = VROUTER_KIND
+
+    simple_attributes = ( ("public_ip", None),
+                          ("public_mac", None),
+                          ("address_pool_id", None),
+                          )
+
+    @property
+    def gateway_ip(self):
+        if not self.address_pool:
+            return None
+        return self.address_pool.gateway_ip
+
+    @property
+    def gateway_mac(self):
+        if not self.address_pool:
+            return None
+        return self.address_pool.gateway_mac
+
+    @property
+    def cidr(self):
+        if not self.address_pool:
+            return None
+        return self.address_pool.cidr
+
+    @property
+    def netbits(self):
+        # return number of bits in the network portion of the cidr
+        if self.cidr:
+            parts = self.cidr.split("/")
+            if len(parts)==2:
+                return int(parts[1].strip())
+        return None
+
+    @property
+    def address_pool(self):
+        if getattr(self, "cached_address_pool", None):
+            return self.cached_address_pool
+        if not self.address_pool_id:
+            return None
+        aps=AddressPool.objects.filter(id=self.address_pool_id)
+        if not aps:
+            return None
+        ap=aps[0]
+        self.cached_address_pool = ap
+        return ap
+
+    @address_pool.setter
+    def address_pool(self, value):
+        if value:
+            value = value.id
+        if (value != self.get_attribute("address_pool_id", None)):
+            self.cached_address_pool=None
+        self.set_attribute("address_pool_id", value)
+
+    def cleanup_addresspool(self):
+        if self.address_pool_id:
+            ap = AddressPool.objects.filter(id=self.address_pool_id)
+            if ap:
+                ap[0].put_address(self.public_ip)
+                self.public_ip = None
+
+    def delete(self, *args, **kwargs):
+        self.cleanup_addresspool()
+        super(VRouterTenant, self).delete(*args, **kwargs)
+
+VRouterTenant.setup_simple_attributes()
+