add default_isolation to slice tosca
diff --git a/xos/tosca/custom_types/xos.m4 b/xos/tosca/custom_types/xos.m4
index 3606601..4f726fc 100644
--- a/xos/tosca/custom_types/xos.m4
+++ b/xos/tosca/custom_types/xos.m4
@@ -588,6 +588,10 @@
                 type: integer
                 default: 10
                 description: Quota of instances that this slice may create.
+            default_isolation:
+                type: string
+                required: false
+                description: default isolation to use when bringing up instances (default to 'vm')
 
     tosca.nodes.Node:
         derived_from: tosca.nodes.Root
diff --git a/xos/tosca/custom_types/xos.yaml b/xos/tosca/custom_types/xos.yaml
index 7a6030e..246c922 100644
--- a/xos/tosca/custom_types/xos.yaml
+++ b/xos/tosca/custom_types/xos.yaml
@@ -776,6 +776,10 @@
                 type: integer
                 default: 10
                 description: Quota of instances that this slice may create.
+            default_isolation:
+                type: string
+                required: false
+                description: default isolation to use when bringing up instances (default to 'vm')
 
     tosca.nodes.Node:
         derived_from: tosca.nodes.Root
diff --git a/xos/tosca/resources/slice.py b/xos/tosca/resources/slice.py
index 2c02365..e37bfc8 100644
--- a/xos/tosca/resources/slice.py
+++ b/xos/tosca/resources/slice.py
@@ -12,7 +12,7 @@
 class XOSSlice(XOSResource):
     provides = "tosca.nodes.Slice"
     xos_model = Slice
-    copyin_props = ["enabled", "description", "slice_url", "max_instances"]
+    copyin_props = ["enabled", "description", "slice_url", "max_instances", "default_isolation"]
 
     def get_xos_args(self):
         args = super(XOSSlice, self).get_xos_args()
diff --git a/xos/tosca/samples/container_slice.yaml b/xos/tosca/samples/container_slice.yaml
new file mode 100644
index 0000000..520bec0
--- /dev/null
+++ b/xos/tosca/samples/container_slice.yaml
@@ -0,0 +1,24 @@
+tosca_definitions_version: tosca_simple_yaml_1_0
+
+description: >
+    * Create a new deployment, controller, and site.
+    * Add a SiteDeployment from the site to the deployment using the controller.
+    * Create a Slice in the Site, with one Instance
+
+imports:
+   - custom_types/xos.yaml
+
+topology_template:
+  node_templates:
+    mysite:
+      type: tosca.nodes.Site
+
+    mysite_containers:
+      type: tosca.nodes.Slice
+      requirements:
+          - slice:
+                node: mysite
+                relationship: tosca.relationships.MemberOfSite
+      properties:
+          default_isolation: container
+