diff --git a/misc/sim/treesim.go b/misc/sim/treesim.go
index 8d4d3f7d..afb681e7 100644
--- a/misc/sim/treesim.go
+++ b/misc/sim/treesim.go
@@ -377,6 +377,14 @@ func dumpDHTSize(store map[[32]byte]*Node) {
 	fmt.Printf("DHT min %d / avg %f / max %d\n", min, avg, max)
 }
 
+func (n *Node) startUDP(listen string) {
+	n.core.DEBUG_setupAndStartGlobalUDPInterface(listen)
+}
+
+func (n *Node) connectUDP(remoteAddr string) {
+	n.core.DEBUG_maybeSendUDPKeys(remoteAddr)
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 var cpuprofile = flag.String("cpuprofile", "", "write cpu profile `file`")
@@ -416,6 +424,22 @@ func main() {
 	  }
 	*/
 	startNetwork(kstore)
+	if true {
+		for _, node := range kstore {
+			node.startUDP("localhost:0")
+			node.connectUDP("localhost:12345")
+			break // just 1
+		}
+		for _, node := range kstore {
+			go func() {
+				// Just dump any packets sent to this node
+				for range node.recv {
+				}
+			}()
+		}
+		var block chan struct{}
+		<-block
+	}
 	//time.Sleep(10*time.Second)
 	// Note that testPaths only works if pressure is turend off
 	//  Otherwise congestion can lead to routing loops?
diff --git a/src/yggdrasil/admin.go b/src/yggdrasil/admin.go
index eec1d71e..3cf2cd2b 100644
--- a/src/yggdrasil/admin.go
+++ b/src/yggdrasil/admin.go
@@ -111,24 +111,60 @@ func (a *admin) handleRequest(conn net.Conn) {
 		}
 		a.core.router.doAdmin(getSessions)
 
-		// Now print it all out
-		conn.Write([]byte(fmt.Sprintf("graph {\n")))
-		for k := range m {
-			var mask [mDepth]switchPort
-			copy(mask[:mDepth], k[:])
-			for mk := range mask {
-				mask[len(mask)-1-mk] = 0
-				if len(m[k]) == 0 {
-					m[k] = fmt.Sprintf("%+v (missing)", k)
+		// Start building a tree from all known nodes
+		type nodeInfo struct {
+			name   string
+			key    [mDepth]switchPort
+			parent [mDepth]switchPort
+		}
+		infos := make(map[[mDepth]switchPort]nodeInfo)
+		// First fill the tree with all known nodes, no parents
+		for k, n := range m {
+			infos[k] = nodeInfo{
+				name: n,
+				key:  k,
+			}
+		}
+		// Now go through and create placeholders for any missing nodes
+		for _, info := range infos {
+			for idx, port := range info.key {
+				if port == 0 {
+					break
 				}
-				if len(m[mask]) == 0 {
-					m[mask] = fmt.Sprintf("%+v (missing)", mask)
+				var key [mDepth]switchPort
+				copy(key[:idx], info.key[:])
+				newInfo, isIn := infos[key]
+				if isIn {
+					continue
 				}
-				if len(m[mask]) > 0 && m[mask] != m[k] {
-					conn.Write([]byte(fmt.Sprintf("  \"%+v\" -- \"%+v\";\n", m[k], m[mask])))
+				newInfo.name = "missing"
+				newInfo.key = key
+				infos[key] = newInfo
+			}
+		}
+		// Now go through and attach parents
+		for _, info := range infos {
+			info.parent = info.key
+			for idx := len(info.parent) - 1; idx >= 0; idx-- {
+				if info.parent[idx] != 0 {
+					info.parent[idx] = 0
 					break
 				}
 			}
+			infos[info.key] = info
+		}
+		// Now print it all out
+		conn.Write([]byte(fmt.Sprintf("digraph {\n")))
+		// First set the labels
+		for _, info := range infos {
+			conn.Write([]byte(fmt.Sprintf("\"%v\" [ label = \"%v\" ];\n", info.key, info.name)))
+		}
+		// Then print the tree structure
+		for _, info := range infos {
+			if info.key == info.parent {
+				continue
+			} // happens for the root, skip it
+			conn.Write([]byte(fmt.Sprintf("  \"%+v\" -> \"%+v\";\n", info.key, info.parent)))
 		}
 		conn.Write([]byte(fmt.Sprintf("}\n")))
 		break