diff --git a/d3mapbuilder.py b/d3mapbuilder.py
index 34e238b..a60665c 100644
--- a/d3mapbuilder.py
+++ b/d3mapbuilder.py
@@ -7,13 +7,16 @@ class D3MapBuilder:
   def build(self):
     output = dict()
 
+    nodes = self._db.get_nodes()
+
     output['nodes'] = [{'group': x.group, 'name': x.name, 'id': x.id,
                         'macs': ', '.join(x.macs)
-                       } for x in self._db.get_nodes() if x.online]
+                       } for x in nodes if x.online]
     output['links'] = [{'source': x.pair[0], 'target': x.pair[1],
                         'distance': x.distance,
                         'strength': x.strength,
-                        'quality': x.quality
+                        'quality': x.quality,
+                        'id': "-".join(nodes[i].id for i in x.pair)
                        } for x in self._db.get_links()]
 
     return json.dumps(output)
diff --git a/node.py b/node.py
index 077d399..57c7f88 100644
--- a/node.py
+++ b/node.py
@@ -13,7 +13,11 @@ class Node():
     # 3 TT
 
   def add_mac(self, mac):
-    self.macs.add(mac.lower())
+    mac = mac.lower()
+    if len(self.macs) == 0:
+      self.id = mac
+
+    self.macs.add(mac)
 
   def __repr__(self):
     return self.macs.__repr__()