diff --git a/lockable.go b/lockable.go
index 321895f..d9988bd 100644
--- a/lockable.go
+++ b/lockable.go
@@ -86,6 +86,12 @@ func LoadLockableExt(ctx *Context, data []byte) (Extension, error) {
   return &ext, nil
 }
 
+
+
+func (ext *LockableExt) HandleLinkSignal(ctx *Context, source NodeID, node *Node, signal LinkSignal) {
+  ctx.Log.Logf("lockable", "LINK_SIGNAL: %+v", signal)
+}
+
 func (ext *LockableExt) Process(ctx *Context, source NodeID, node *Node, signal Signal) {
   ctx.Log.Logf("signal", "LOCKABLE_PROCESS: %s", node.ID)
 
@@ -121,6 +127,11 @@ func (ext *LockableExt) Process(ctx *Context, source NodeID, node *Node, signal
       }
     }
   case Direct:
+    switch sig := signal.(type) {
+    case LinkSignal:
+      ext.HandleLinkSignal(ctx, source, node, sig)
+    default:
+    }
   default:
   }
 }
diff --git a/lockable_test.go b/lockable_test.go
new file mode 100644
index 0000000..ed8029c
--- /dev/null
+++ b/lockable_test.go
@@ -0,0 +1,13 @@
+package graphvent
+
+import (
+  "testing"
+)
+
+func TestLockableLink(t *testing.T) {
+  ctx := logTestContext(t, []string{"lockable", "signal"})
+  LockableType := NodeType("TEST_LOCKABLE")
+  err := ctx.RegisterNodeType(LockableType, []ExtType{LockableExtType})
+  fatalErr(t, err)
+}
+
diff --git a/signal.go b/signal.go
index 030945d..ec25568 100644
--- a/signal.go
+++ b/signal.go
@@ -98,6 +98,18 @@ func NewStatusSignal(status string, source NodeID) StatusSignal {
   }
 }
 
+type LinkSignal struct {
+  IDSignal
+  State string `json:"state"`
+}
+
+func NewLinkSignal(state string, source NodeID) LinkSignal {
+  return LinkSignal{
+    IDSignal: NewIDSignal("link", Direct, source),
+    State: state,
+  }
+}
+
 type StartChildSignal struct {
   IDSignal
   Action string `json:"action"`