diff --git a/utils/tracers/ndn-app-delay-tracer.cc b/utils/tracers/ndn-app-delay-tracer.cc
new file mode 100644
index 0000000..c84f176
--- /dev/null
+++ b/utils/tracers/ndn-app-delay-tracer.cc
@@ -0,0 +1,158 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013 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-app-delay-tracer.h"
+#include "ns3/node.h"
+#include "ns3/packet.h"
+#include "ns3/config.h"
+#include "ns3/names.h"
+#include "ns3/callback.h"
+
+#include "ns3/ndn-app.h"
+#include "ns3/ndn-interest.h"
+#include "ns3/ndn-content-object.h"
+#include "ns3/simulator.h"
+#include "ns3/node-list.h"
+#include "ns3/log.h"
+
+#include <boost/lexical_cast.hpp>
+#include <boost/make_shared.hpp>
+
+#include <fstream>
+
+NS_LOG_COMPONENT_DEFINE ("ndn.AppDelayTracer");
+
+using namespace std;
+
+namespace ns3 {
+namespace ndn {
+
+
+boost::tuple< boost::shared_ptr<std::ostream>, std::list<Ptr<AppDelayTracer> > >
+AppDelayTracer::InstallAll (const std::string &file)
+{
+  using namespace boost;
+  using namespace std;
+  
+  std::list<Ptr<AppDelayTracer> > tracers;
+  boost::shared_ptr<std::ofstream> outputStream = make_shared<std::ofstream> ();
+
+  outputStream->open (file.c_str (), std::ios_base::out | std::ios_base::trunc);
+  if (!outputStream->is_open ())
+    return boost::make_tuple (outputStream, tracers);
+
+  for (NodeList::Iterator node = NodeList::Begin ();
+       node != NodeList::End ();
+       node++)
+    {
+      NS_LOG_DEBUG ("Node: " << (*node)->GetId ());
+
+      Ptr<AppDelayTracer> trace = Create<AppDelayTracer> (outputStream, *node);
+      tracers.push_back (trace);
+    }
+
+  if (tracers.size () > 0)
+    {
+      // *m_l3RateTrace << "# "; // not necessary for R's read.table
+      tracers.front ()->PrintHeader (*outputStream);
+      *outputStream << "\n";
+    }
+
+  return boost::make_tuple (outputStream, tracers);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+
+AppDelayTracer::AppDelayTracer (boost::shared_ptr<std::ostream> os, Ptr<Node> node)
+: m_nodePtr (node)
+, m_os (os)
+{
+  m_node = boost::lexical_cast<string> (m_nodePtr->GetId ());
+
+  Connect ();
+
+  string name = Names::FindName (node);
+  if (!name.empty ())
+    {
+      m_node = name;
+    }
+}
+
+AppDelayTracer::AppDelayTracer (boost::shared_ptr<std::ostream> os, const std::string &node)
+: m_node (node)
+, m_os (os)
+{
+  Connect ();
+}
+
+AppDelayTracer::~AppDelayTracer ()
+{
+};
+
+
+void
+AppDelayTracer::Connect ()
+{
+  Config::ConnectWithoutContext ("/NodeList/"+m_node+"/ApplicationList/*/LastRetransmittedInterestDataDelay",
+                                 MakeCallback (&AppDelayTracer::LastRetransmittedInterestDataDelay, this));
+
+  Config::ConnectWithoutContext ("/NodeList/"+m_node+"/ApplicationList/*/LastRetransmittedInterestDataDelay",
+                                 MakeCallback (&AppDelayTracer::FirstInterestDataDelay, this));
+}
+
+void
+AppDelayTracer::PrintHeader (std::ostream &os) const
+{
+  os << "Node" << "\t"
+     << "AppId" << "\t"
+     << "SeqNo" << "\t"
+
+     << "Type" << "\t"
+     << "DelayS" << "\t"
+     << "DelayUS" << "\n";
+}
+
+void 
+AppDelayTracer::LastRetransmittedInterestDataDelay (Ptr<App> app, uint32_t seqno, Time delay)
+{
+  *m_os << m_node << "\t"
+        << app->GetId () << "\t"
+        << seqno << "\t"
+        << "LastDelay" << "\t"
+        << delay.ToDouble (Time::S) << "\t"
+        << delay.ToDouble (Time::US) << "\n";
+}
+  
+void 
+AppDelayTracer::FirstInterestDataDelay (Ptr<App> app, uint32_t seqno, Time delay)
+{
+  *m_os << m_node << "\t"
+        << app->GetId () << "\t"
+        << seqno << "\t"
+        << "FullDelay" << "\t"
+        << delay.ToDouble (Time::S) << "\t"
+        << delay.ToDouble (Time::US) << "\n";
+}
+
+
+} // namespace ndn
+} // namespace ns3
diff --git a/utils/tracers/ndn-app-delay-tracer.h b/utils/tracers/ndn-app-delay-tracer.h
new file mode 100644
index 0000000..af0007f
--- /dev/null
+++ b/utils/tracers/ndn-app-delay-tracer.h
@@ -0,0 +1,109 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013 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>
+ */
+
+#ifndef CCNX_APP_DELAY_TRACER_H
+#define CCNX_APP_DELAY_TRACER_H
+
+#include "ns3/ptr.h"
+#include "ns3/simple-ref-count.h"
+#include <ns3/nstime.h>
+#include <ns3/event-id.h>
+
+#include <boost/tuple/tuple.hpp>
+#include <boost/shared_ptr.hpp>
+#include <list>
+
+namespace ns3 {
+
+class Node;
+class Packet;
+
+namespace ndn {
+
+class App;
+
+/**
+ * @ingroup ndn
+ * @brief  network-layer tracer for aggregate packet counts
+ */
+class AppDelayTracer : public SimpleRefCount<AppDelayTracer>
+{
+public:
+  /**
+   * @brief Helper method to install tracers on all simulation nodes
+   *
+   * @param file File to which traces will be written
+   * @param averagingPeriod How often data will be written into the trace file (default, every half second)
+   *
+   * @returns a tuple of reference to output stream and list of tracers. !!! Attention !!! This tuple needs to be preserved
+   *          for the lifetime of simulation, otherwise SEGFAULTs are inevitable
+   * 
+   */
+  static boost::tuple< boost::shared_ptr<std::ostream>, std::list<Ptr<AppDelayTracer> > >
+  InstallAll (const std::string &file);
+
+  /**
+   * @brief Trace constructor that attaches to all applications on the node using node's pointer
+   * @param os    reference to the output stream
+   * @param node  pointer to the node
+   */
+  AppDelayTracer (boost::shared_ptr<std::ostream> os, Ptr<Node> node);
+
+  /**
+   * @brief Trace constructor that attaches to all applications on the node using node's name
+   * @param os        reference to the output stream
+   * @param nodeName  name of the node registered using Names::Add
+   */
+  AppDelayTracer (boost::shared_ptr<std::ostream> os, const std::string &node);
+
+  /**
+   * @brief Destructor
+   */
+  ~AppDelayTracer ();
+
+  /**
+   * @brief Print head of the trace (e.g., for post-processing)
+   *
+   * @param os reference to output stream
+   */
+  void
+  PrintHeader (std::ostream &os) const;
+  
+private:
+  void
+  Connect ();
+
+  void 
+  LastRetransmittedInterestDataDelay (Ptr<App> app, uint32_t seqno, Time delay);
+  
+  void 
+  FirstInterestDataDelay (Ptr<App> app, uint32_t seqno, Time delay);
+  
+private:
+  std::string m_node;
+  Ptr<Node> m_nodePtr;
+
+  boost::shared_ptr<std::ostream> m_os;
+};
+
+} // namespace ndn
+} // namespace ns3
+
+#endif // CCNX_CS_TRACER_H
diff --git a/utils/tracers/ndn-cs-tracer.cc b/utils/tracers/ndn-cs-tracer.cc
index 6cab66f..2200665 100644
--- a/utils/tracers/ndn-cs-tracer.cc
+++ b/utils/tracers/ndn-cs-tracer.cc
@@ -113,10 +113,10 @@
 void
 CsTracer::Connect ()
 {
-  Config::Connect ("/NodeList/"+m_node+"/$ns3::ndn::ContentStore/CacheHits",
-                   MakeCallback (&CsTracer::CacheHits, this));
-  Config::Connect ("/NodeList/"+m_node+"/$ns3::ndn::ContentStore/CacheMisses",
-                   MakeCallback (&CsTracer::CacheMisses, this));
+  Config::ConnectWithoutContext ("/NodeList/"+m_node+"/$ns3::ndn::ContentStore/CacheHits",
+                                 MakeCallback (&CsTracer::CacheHits, this));
+  Config::ConnectWithoutContext ("/NodeList/"+m_node+"/$ns3::ndn::ContentStore/CacheMisses",
+                                 MakeCallback (&CsTracer::CacheMisses, this));
 
   Reset ();  
 }
@@ -173,15 +173,13 @@
 }
 
 void 
-CsTracer::CacheHits (std::string context,
-                     Ptr<const InterestHeader>, Ptr<const ContentObjectHeader>)
+CsTracer::CacheHits (Ptr<const InterestHeader>, Ptr<const ContentObjectHeader>)
 {
   m_stats.m_cacheHits ++;
 }
 
 void 
-CsTracer::CacheMisses (std::string context, 
-                       Ptr<const InterestHeader>)
+CsTracer::CacheMisses (Ptr<const InterestHeader>)
 {
   m_stats.m_cacheMisses ++;
 }
diff --git a/utils/tracers/ndn-cs-tracer.h b/utils/tracers/ndn-cs-tracer.h
index af7419a..b52de9c 100644
--- a/utils/tracers/ndn-cs-tracer.h
+++ b/utils/tracers/ndn-cs-tracer.h
@@ -117,12 +117,10 @@
   Connect ();
 
   void 
-  CacheHits (std::string context,
-  Ptr<const InterestHeader>, Ptr<const ContentObjectHeader>);
+  CacheHits (Ptr<const InterestHeader>, Ptr<const ContentObjectHeader>);
   
   void 
-  CacheMisses (std::string context,
-  Ptr<const InterestHeader>);
+  CacheMisses (Ptr<const InterestHeader>);
 
 private:
   void