diff --git a/utils/ndn-limits-window.cc b/utils/ndn-limits-window.cc
new file mode 100644
index 0000000..6f371b4
--- /dev/null
+++ b/utils/ndn-limits-window.cc
@@ -0,0 +1,83 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2011 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#include "ndn-limits-window.h"
+
+#include "ns3/log.h"
+#include "ns3/simulator.h"
+#include "ns3/random-variable.h"
+
+NS_LOG_COMPONENT_DEFINE ("ndn.Limits.Window");
+
+namespace ns3 {
+namespace ndn {
+
+NS_OBJECT_ENSURE_REGISTERED (Limits);
+
+TypeId
+LimitsWindow::GetTypeId ()
+{
+  static TypeId tid = TypeId ("ns3::ndn::Limits::Window")
+    .SetGroupName ("Ndn")
+    .SetParent <Limits> () 
+    .AddConstructor <LimitsWindow> ()
+    
+    .AddTraceSource ("Outstanding",
+                     "Number of outstanding interests",
+                     MakeTraceSourceAccessor (&LimitsWindow::m_outstanding))
+    ;
+  return tid;
+}
+
+bool
+LimitsWindow::IsBelowLimit ()
+{
+  if (!IsEnabled ()) return true;
+
+  if (m_curMaxLimit - m_outstanding >= 1.0)
+    {
+      // static UniformVariable acceptanceProbability (0, m_curMaxLimit);
+      // double value = acceptanceProbability.GetValue ();
+      double value = m_outstanding + 1;
+      
+      if (m_outstanding < value)
+        {
+          m_outstanding += 1.0;
+          return true;
+        }
+      else
+        return false;
+    }
+  else
+    return false;
+}
+
+void
+LimitsWindow::RemoveOutstanding ()
+{
+  if (!IsEnabled ()) return; 
+
+  NS_LOG_DEBUG (m_outstanding);
+  NS_ASSERT_MSG (m_outstanding >= (uint32_t)1, "Should not be possible, unless we decreasing this number twice somewhere");
+  m_outstanding -= 1;
+}
+
+} // namespace ndn
+} // namespace ns3