diff --git a/examples/congestion-pop.cc b/examples/congestion-pop.cc
index aed4aa9..0c65860 100644
--- a/examples/congestion-pop.cc
+++ b/examples/congestion-pop.cc
@@ -45,101 +45,126 @@
 
 NS_LOG_COMPONENT_DEFINE ("Scenario");
 
-void PrintTime ()
-{
-  cout << "Progress: " << Simulator::Now ().ToDouble (Time::S) << "s" << endl;
+// void PrintTime ()
+// {
+//   cout << "Progress: " << Simulator::Now ().ToDouble (Time::S) << "s" << endl;
 
-  Simulator::Schedule (Seconds (1.0), PrintTime);
-}
+//   Simulator::Schedule (Seconds (1.0), PrintTime);
+// }
 
 class Experiment
 {
 public:
   Experiment ()
     : m_rand (0,52)
-    , reader ("/sprint")
+    , reader (0)
   { }
-  
+
+  ~Experiment ()
+  {
+    if (reader != 0) delete reader;
+  }
+    
   void
-  ConfigureCcnxTopology ()
+  ConfigureTopology ()
   {
     Names::Clear ();
+    cout << "Configure Topology\n";
+    if (reader != 0) delete reader;
+    reader = new RocketfuelWeightsReader ("/sprint");
     
     string weights   ("./src/NDNabstraction/examples/sprint-pops.weights");
     string latencies ("./src/NDNabstraction/examples/sprint-pops.latencies");
     string positions ("./src/NDNabstraction/examples/sprint-pops.positions");
   
-    RocketfuelWeightsReader reader ("/sprint");
-
-    reader.SetFileName (positions);
-    reader.SetFileType (RocketfuelWeightsReader::POSITIONS);
-    reader.Read ();
+    reader->SetFileName (positions);
+    reader->SetFileType (RocketfuelWeightsReader::POSITIONS);
+    reader->Read ();
   
-    reader.SetFileName (weights);
-    reader.SetFileType (RocketfuelWeightsReader::WEIGHTS);    
-    reader.Read ();
+    reader->SetFileName (weights);
+    reader->SetFileType (RocketfuelWeightsReader::WEIGHTS);    
+    reader->Read ();
 
-    reader.SetFileName (latencies);
-    reader.SetFileType (RocketfuelWeightsReader::LATENCIES);    
-    reader.Read ();
+    reader->SetFileName (latencies);
+    reader->SetFileType (RocketfuelWeightsReader::LATENCIES);    
+    reader->Read ();
     
-    reader.Commit ();
-    NS_ASSERT_MSG (reader.LinksSize () != 0, "Problems reading the topology file. Failing.");
-    
-    NS_LOG_INFO("Nodes = " << reader.GetNodes ().GetN());
-    NS_LOG_INFO("Links = " << reader.LinksSize ());
-  
-    // ------------------------------------------------------------
-    // -- Read topology data.
-    // --------------------------------------------
-        
+    reader->Commit ();
+  }
+
+  void InstallCcnxStack ()
+  {
     InternetStackHelper stack;
     Ipv4GlobalRoutingHelper ipv4RoutingHelper ("ns3::Ipv4GlobalRoutingOrderedNexthops");
     stack.SetRoutingHelper (ipv4RoutingHelper);
-    stack.Install (reader.GetNodes ());
+    stack.Install (reader->GetNodes ());
 
-    reader.AssignIpv4Addresses (Ipv4Address ("10.0.0.0"));
+    reader->AssignIpv4Addresses (Ipv4Address ("10.0.0.0"));
     
     // Install CCNx stack
-    NS_LOG_INFO ("Installing CCNx stack");
+    cout << "Installing CCNx stack\n";
     CcnxStackHelper ccnxHelper;
     ccnxHelper.SetForwardingStrategy ("ns3::CcnxBestRouteStrategy");
     ccnxHelper.EnableLimits (true, Seconds(0.1));
     ccnxHelper.SetDefaultRoutes (false);
     ccnxHelper.InstallAll ();
-  }
 
-  void
-  ConfigureRouting ()
-  {
-    CcnxStackHelper ccnxHelper;
     // // Populate FIB based on IPv4 global routing controller
     ccnxHelper.InstallFakeGlobalRoutes ();
     ccnxHelper.InstallRoutesToAll ();
   }
   
-  ApplicationContainer
-  AddCcnxRandomApplications (uint16_t numStreams)
+  void InstallIpStack ()
   {
-    map<uint32_t, set<uint32_t> > streams;
-    ApplicationContainer apps;
+    InternetStackHelper stack;
+    stack.Install (reader->GetNodes ());
+    reader->AssignIpv4Addresses (Ipv4Address ("10.0.0.0"));
+
+    Ipv4GlobalRoutingHelper::PopulateRoutingTables ();
+  }
+
+  void
+  GenerateRandomPairs (uint16_t numStreams)
+  {
+    m_pairs.clear ();
+    // map<uint32_t, set<uint32_t> > streams;
+    set<uint32_t> usedNodes;
     
     uint16_t createdStreams = 0;
     uint16_t guard = 0;
     while (createdStreams < numStreams && guard < (numeric_limits<uint16_t>::max ()-1))
       {
         guard ++;
-        
+
         uint32_t node1_num = m_rand.GetValue ();
         uint32_t node2_num = m_rand.GetValue ();
 
         if (node1_num == node2_num)
           continue;
 
-        if (streams[node1_num].count (node2_num) > 0) // don't create duplicate streams
-          continue;
-        
-        streams[node1_num].insert (node2_num);
+        if (usedNodes.count (node1_num) > 0 ||
+            usedNodes.count (node2_num) > 0 )
+          {
+            continue; // don't reuse nodes
+          }
+
+        usedNodes.insert (node1_num);
+        usedNodes.insert (node2_num);
+
+        m_pairs.push_back (make_tuple (node1_num, node2_num));
+        createdStreams ++;
+      }
+  }
+  
+  ApplicationContainer
+  AddCcnxApplications ()
+  {
+    ApplicationContainer apps;
+
+    for (list<tuple<uint32_t,uint32_t> >::iterator i = m_pairs.begin (); i != m_pairs.end (); i++)
+      {
+        uint32_t node1_num = i->get<0> ();
+        uint32_t node2_num = i->get<1> ();
 
         Ptr<Node> node1 = Names::Find<Node> ("/sprint", lexical_cast<string> (node1_num));
         Ptr<Node> node2 = Names::Find<Node> ("/sprint", lexical_cast<string> (node2_num));
@@ -157,26 +182,66 @@
 
         apps.Add
           (producerHelper.Install (node2));
-
-        createdStreams ++;
       }
 
     return apps;
   }
 
+  ApplicationContainer
+  AddTcpApplications ()
+  {
+    ApplicationContainer apps;
+
+    uint32_t streamId = 0;
+    const static uint32_t base_port = 10;
+    for (list<tuple<uint32_t,uint32_t> >::iterator i = m_pairs.begin (); i != m_pairs.end (); i++)
+      {
+        uint32_t node1_num = i->get<0> ();
+        uint32_t node2_num = i->get<1> ();
+
+        Ptr<Node> node1 = Names::Find<Node> ("/sprint", lexical_cast<string> (node2_num));
+        Ptr<Node> node2 = Names::Find<Node> ("/sprint", lexical_cast<string> (node1_num));
+
+        Ptr<Ipv4> ipv4 = node1->GetObject<Ipv4> ();
+        // ipv4->GetAddress (0, 0);
+
+        // to make sure we don't reuse the same port numbers for different flows, just make all port numbers unique
+        PacketSinkHelper consumerHelper ("ns3::TcpSocketFactory",
+                                         InetSocketAddress (Ipv4Address::GetAny (), base_port + streamId));
+
+        BulkSendHelper producerHelper ("ns3::TcpSocketFactory",
+                                       InetSocketAddress (ipv4->GetAddress (1, 0).GetLocal (), base_port + streamId));
+        // cout << "SendTo: " <<  ipv4->GetAddress (1, 0).GetLocal () << endl;
+        producerHelper.SetAttribute ("MaxBytes", UintegerValue (2081040)); // equal to 2001 ccnx packets
+        
+        apps.Add
+          (consumerHelper.Install (node1));
+
+        apps.Add
+          (producerHelper.Install (node2));
+
+        streamId++;
+      }
+
+    return apps;
+  }
+
+
   void
   Run (const Time &finishTime)
   {
     cout << "Run Simulation.\n";
     Simulator::Stop (finishTime);
-    Simulator::Schedule (Seconds (1.0), PrintTime);
+    // Simulator::Schedule (Seconds (1.0), PrintTime);
     Simulator::Run ();
     Simulator::Destroy ();
     cout << "Done.\n";
   }
 
   UniformVariable m_rand;
-  RocketfuelWeightsReader reader;
+  RocketfuelWeightsReader *reader;
+
+  list<tuple<uint32_t,uint32_t> > m_pairs;
 };
 
 
@@ -187,6 +252,9 @@
   
   Config::SetDefault ("ns3::PointToPointNetDevice::DataRate", StringValue ("1Mbps"));
   Config::SetDefault ("ns3::DropTailQueue::MaxPackets", StringValue ("60"));
+  Config::SetDefault ("ns3::TcpSocket::SegmentSize", StringValue ("1040"));
+  
+  Config::SetDefault ("ns3::BulkSendApplication::SendSize", StringValue ("1040"));
 
   uint32_t maxRuns = 1;
   uint32_t startRun = 0;
@@ -202,31 +270,57 @@
 
       Experiment experiment;
       cout << "Run " << run << endl;
-      
-      experiment.ConfigureCcnxTopology ();
-      ApplicationContainer apps = experiment.AddCcnxRandomApplications (20);
-      experiment.ConfigureRouting ();
-  
       string prefix = "run-" + lexical_cast<string> (run) + "-";
 
+      experiment.GenerateRandomPairs (20);
       ofstream of_nodes ((prefix + "apps.log").c_str ());
-      for (uint32_t i = 0; i < apps.GetN () / 2; i++) 
+      for (list<tuple<uint32_t,uint32_t> >::iterator i = experiment.m_pairs.begin (); i != experiment.m_pairs.end (); i++)
         {
-          apps.Get (i*2)->SetStartTime (Seconds (i));
-          apps.Get (i*2 + 1)->SetStartTime (Seconds (i));
-          
-          of_nodes << "From " << apps.Get (i*2)->GetNode ()->GetId ()
-                   << " to "  << apps.Get (i*2 + 1)->GetNode ()->GetId ();
+          of_nodes << "From " << i->get<0> ()
+                   << " to "  << i->get<1> ();
           of_nodes << "\n";
         }
       of_nodes.close ();
 
-      CcnxTraceHelper traceHelper;
-      traceHelper.EnableRateL3All (prefix + "rate-trace.log");
-      // traceHelper.EnableSeqsAppAll ("ns3::CcnxConsumerCbr", prefix + "consumers-seqs.log");
-      traceHelper.EnableSeqsAppAll ("ns3::CcnxConsumerWindow", prefix + "consumers-seqs.log");
+      cout << "NDN experiment\n";
+      // NDN
+      {
+        experiment.ConfigureTopology ();
+        experiment.InstallCcnxStack ();
+        ApplicationContainer apps = experiment.AddCcnxApplications ();
 
-      experiment.Run (Seconds (200.0));
+        for (uint32_t i = 0; i < apps.GetN () / 2; i++) 
+          {
+            apps.Get (i*2)->SetStartTime (Seconds (i));
+            apps.Get (i*2 + 1)->SetStartTime (Seconds (i));
+          }
+
+        CcnxTraceHelper traceHelper;
+        // traceHelper.EnableRateL3All (prefix + "rate-trace.log");
+        // traceHelper.EnableSeqsAppAll ("ns3::CcnxConsumerCbr", prefix + "consumers-seqs.log");
+        traceHelper.EnableSeqsAppAll ("ns3::CcnxConsumerWindow", prefix + "consumers-seqs.log");
+
+        experiment.Run (Seconds (200.0));
+      }
+
+      cout << "TCP experiment\n";
+      // TCP
+      {
+        experiment.ConfigureTopology ();
+        experiment.InstallIpStack ();
+        ApplicationContainer apps = experiment.AddTcpApplications ();
+
+        for (uint32_t i = 0; i < apps.GetN () / 2; i++) 
+          {
+            apps.Get (i*2)->SetStartTime (Seconds (i));
+            apps.Get (i*2 + 1)->SetStartTime (Seconds (i));
+          }
+
+        CcnxTraceHelper traceHelper;
+        traceHelper.EnableIpv4SeqsAppAll (prefix + "tcp-consumers-seqs.log");
+
+        experiment.Run (Seconds (200.0));
+      }
     }
 
   // cout << "Finish congestion-pop scenario\n";
diff --git a/examples/congestion-tcp-pop.cc b/examples/congestion-tcp-pop.cc
deleted file mode 100644
index c1ac443..0000000
--- a/examples/congestion-tcp-pop.cc
+++ /dev/null
@@ -1,231 +0,0 @@
-/* -*-  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: Ilya Moiseenko <iliamo@cs.ucla.edu>
- */
-
-
-#include "ns3/core-module.h"
-#include "ns3/network-module.h"
-#include "ns3/point-to-point-module.h"
-#include "ns3/NDNabstraction-module.h"
-#include "ns3/point-to-point-grid.h"
-#include "ns3/ipv4-global-routing-helper.h"
-#include "ns3/random-variable.h"
-#include "ns3/internet-module.h"
-#include "ns3/applications-module.h"
-#include "ns3/config-store.h"
-
-#include <iostream>
-#include <sstream>
-#include <map>
-#include <list>
-#include <set>
-#include "ns3/rocketfuel-topology-reader.h"
-
-#include "../helper/tracers/ipv4-seqs-app-tracer.h"
-
-#include <boost/lexical_cast.hpp>
-#include <boost/foreach.hpp>
-
-using namespace ns3;
-using namespace std;
-using namespace boost;
-
-NS_LOG_COMPONENT_DEFINE ("Scenario");
-
-void PrintTime ()
-{
-  cout << "Progress: " << Simulator::Now ().ToDouble (Time::S) << "s" << endl;
-
-  Simulator::Schedule (Seconds (1.0), PrintTime);
-}
-
-class Experiment
-{
-public:
-  Experiment ()
-    : m_rand (0,52)
-    , reader ("/sprint")
-  { }
-
-  void
-  ConfigureIpv4Topology ()
-  {
-    Names::Clear ();
-    
-    string weights   ("./src/NDNabstraction/examples/sprint-pops.weights");
-    string latencies ("./src/NDNabstraction/examples/sprint-pops.latencies");
-    string positions ("./src/NDNabstraction/examples/sprint-pops.positions");
-  
-    reader.SetFileName (positions);
-    reader.SetFileType (RocketfuelWeightsReader::POSITIONS);
-    reader.Read ();
-  
-    reader.SetFileName (weights);
-    reader.SetFileType (RocketfuelWeightsReader::WEIGHTS);    
-    reader.Read ();
-
-    reader.SetFileName (latencies);
-    reader.SetFileType (RocketfuelWeightsReader::LATENCIES);    
-    reader.Read ();
-    
-    reader.Commit ();
-    NS_ASSERT_MSG (reader.LinksSize () != 0, "Problems reading the topology file. Failing.");
-    
-    NS_LOG_INFO("Nodes = " << reader.GetNodes ().GetN());
-    NS_LOG_INFO("Links = " << reader.LinksSize ());
-
-    InternetStackHelper stack;
-    stack.Install (reader.GetNodes ());
-    reader.AssignIpv4Addresses (Ipv4Address ("10.0.0.0"));
-  }
-
-  void
-  ConfigureRouting ()
-  {
-    Ipv4GlobalRoutingHelper::PopulateRoutingTables ();
-
-    // m_rand = UniformVariable (0, reader.GetNodes ().GetN());
-  }
-  
-  ApplicationContainer
-  AddTcpRandomApplications (uint16_t numStreams)
-  {
-    map<uint32_t, set<uint32_t> > streams;
-    ApplicationContainer apps;
-
-    const static uint32_t base_port = 10;
-    uint16_t createdStreams = 0;
-    uint16_t guard = 0;
-    while (createdStreams < numStreams && guard < (numeric_limits<uint16_t>::max ()-1))
-      {
-        guard ++;
-        
-        uint32_t node1_num = m_rand.GetValue ();
-        uint32_t node2_num = m_rand.GetValue ();
-
-        if (node1_num == node2_num)
-          continue;
-
-        if (streams[node1_num].count (node2_num) > 0) // don't create duplicate streams
-          continue;
-        
-        streams[node1_num].insert (node2_num);
-
-        Ptr<Node> node1 = Names::Find<Node> ("/sprint", lexical_cast<string> (node1_num));
-        Ptr<Node> node2 = Names::Find<Node> ("/sprint", lexical_cast<string> (node2_num));
-
-        Ptr<Ipv4> ipv4 = node1->GetObject<Ipv4> ();
-        // ipv4->GetAddress (0, 0);
-
-        // to make sure we don't reuse the same port numbers for different flows, just make all port numbers unique
-        PacketSinkHelper consumerHelper ("ns3::TcpSocketFactory",
-                                         InetSocketAddress (Ipv4Address::GetAny (), base_port + createdStreams));
-
-        BulkSendHelper producerHelper ("ns3::TcpSocketFactory",
-                                       InetSocketAddress (ipv4->GetAddress (1, 0).GetLocal (), base_port + createdStreams));
-        // cout << "SendTo: " <<  ipv4->GetAddress (1, 0).GetLocal () << endl;
-        producerHelper.SetAttribute ("MaxBytes", UintegerValue (2081040)); // equal to 2001 ccnx packets
-        
-        apps.Add
-          (consumerHelper.Install (node1));
-
-        apps.Add
-          (producerHelper.Install (node2));
-
-        createdStreams ++;
-      }
-
-    return apps;
-  }
-
-  void
-  Run (const Time &finishTime)
-  {
-    cout << "Run Simulation.\n";
-    Simulator::Stop (finishTime);
-    // Simulator::Schedule (Seconds (1.0), PrintTime);
-    Simulator::Run ();
-    Simulator::Destroy ();
-    cout << "Done.\n";
-  }
-
-  UniformVariable m_rand;
-  RocketfuelWeightsReader reader;
-};
-
-int 
-main (int argc, char *argv[])
-{
-  cout << "Begin congestion-pop scenario\n";
-  Packet::EnableChecking();
-  Packet::EnablePrinting();
-  
-  Config::SetDefault ("ns3::PointToPointNetDevice::DataRate", StringValue ("1Mbps"));
-  Config::SetDefault ("ns3::DropTailQueue::MaxPackets", StringValue ("20"));
-  Config::SetDefault ("ns3::TcpSocket::SegmentSize", StringValue ("1040"));
-  
-  Config::SetDefault ("ns3::BulkSendApplication::SendSize", StringValue ("1040"));
-
-  // Config::SetDefault ("ns3::ConfigStore::Filename", StringValue ("attributes.xml"));
-  // Config::SetDefault ("ns3::ConfigStore::Mode", StringValue ("Save"));
-  // Config::SetDefault ("ns3::ConfigStore::FileFormat", StringValue ("Xml"));
-  
-  uint32_t maxRuns = 1;
-  uint32_t startRun = 0;
-  CommandLine cmd;
-  cmd.AddValue ("start", "Initial run number", startRun);
-  cmd.AddValue ("runs", "Number of runs", maxRuns);
-  cmd.Parse (argc, argv);
-
-  // ConfigStore config;
-  // config.ConfigureDefaults ();
-
-  for (uint32_t run = startRun; run < startRun + maxRuns; run++)
-    {
-      Config::SetGlobal ("RngRun", IntegerValue (run));
-      cout << "seed = " << SeedManager::GetSeed () << ", run = " << SeedManager::GetRun () << endl;
-      
-      Experiment experiment;
-      cout << "Run " << run << endl;
-      
-      experiment.ConfigureIpv4Topology ();
-      ApplicationContainer apps = experiment.AddTcpRandomApplications (20);
-      experiment.ConfigureRouting ();
-
-      string prefix = "run-tcp-" + lexical_cast<string> (run) + "-";      
-
-      ofstream of_nodes ((prefix + "apps.log").c_str ());
-      for (uint32_t i = 0; i < apps.GetN () / 2; i++) 
-        {
-          of_nodes << "From " << apps.Get (i*2)->GetNode ()->GetId ()
-                   << " to "  << apps.Get (i*2 + 1)->GetNode ()->GetId ();
-          of_nodes << "\n";
-        }
-
-      CcnxTraceHelper traceHelper;
-      traceHelper.EnableIpv4SeqsAppAll (prefix + "consumers-seqs.log");
-
-      // config.ConfigureAttributes ();  
-
-      experiment.Run (Seconds (200.0));
-    }
-
-  // cout << "Finish congestion-pop scenario\n";
-  return 0;
-}
diff --git a/wscript b/wscript
index 45b88b9..735186f 100644
--- a/wscript
+++ b/wscript
@@ -114,12 +114,6 @@
         obj = bld.create_ns3_program('congestion-pop', ['NDNabstraction'])
         obj.source = 'examples/congestion-pop.cc'
 
-        obj = bld.create_ns3_program('congestion-tcp-pop', ['NDNabstraction'])
-        obj.source = 'examples/congestion-tcp-pop.cc'
-
-        #obj = bld.create_ns3_program('congestion-pop', ['NDNabstraction'])
-        #obj.source = 'examples/congestion-pop.cc'
-        
         #obj = bld.create_ns3_program('link-failure-sprint', ['NDNabstraction'])
         #obj.source = 'examples/link-failure-sprint.cc'