diff --git a/vrtManager/instance.py b/vrtManager/instance.py
index 143465b..76f9360 100644
--- a/vrtManager/instance.py
+++ b/vrtManager/instance.py
@@ -986,6 +986,21 @@ class wvmInstance(wvmConnect):
                 source.set('bridge', bridge_name)
                 source = interface.find('filterref')
 
+                if net_filter:
+                    if source is not None: source.set('filter', net_filter)
+                    else:
+                        element = ElementTree.Element("filterref")
+                        element.attrib['filter'] = net_filter
+                        interface.append(element)
+                else:
+                    if source is not None: interface.remove(source)
+            elif interface.get('type') == 'network':
+                source = interface.find('mac')
+                source.set('address', net_mac)
+                source = interface.find('source')
+                source.set('network', net_source)
+                source = interface.find('filterref')
+
                 if net_filter:
                     if source is not None: source.set('filter', net_filter)
                     else: