1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2015 Universita' degli Studi di Napoli "Federico II"
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation;
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
17  *
18  * Author: Pasquale Imputato <p.imputato@gmail.com>
19  * Author: Stefano Avallone <stefano.avallone@unina.it>
20  */
21 
22 #include "ns3/core-module.h"
23 #include "ns3/network-module.h"
24 #include "ns3/internet-module.h"
25 #include "ns3/point-to-point-module.h"
26 #include "ns3/applications-module.h"
27 #include "ns3/traffic-control-module.h"
28 #include "ns3/flow-monitor-module.h"
29 
30 // This simple example shows how to use TrafficControlHelper to install a
31 // QueueDisc on a device.
32 //
33 // The default QueueDisc is a pfifo_fast with a capacity of 1000 packets (as in
34 // Linux). However, in this example, we install a RedQueueDisc with a capacity
35 // of 10000 packets.
36 //
37 // Network topology
38 //
39 //       10.1.1.0
40 // n0 -------------- n1
41 //    point-to-point
42 //
43 // The output will consist of all the traced changes in the length of the RED
44 // internal queue and in the length of the netdevice queue:
45 //
46 //    DevicePacketsInQueue 0 to 1
47 //    TcPacketsInQueue 7 to 8
48 //    TcPacketsInQueue 8 to 9
49 //    DevicePacketsInQueue 1 to 0
50 //    TcPacketsInQueue 9 to 8
51 //
52 // plus some statistics collected at the network layer (by the flow monitor)
53 // and the application layer. Finally, the number of packets dropped by the
54 // queuing discipline, the number of packets dropped by the netdevice and
55 // the number of packets requeued by the queuing discipline are reported.
56 //
57 // If the size of the DropTail queue of the netdevice were increased from 1
58 // to a large number (e.g. 1000), one would observe that the number of dropped
59 // packets goes to zero, but the latency grows in an uncontrolled manner. This
60 // is the so-called bufferbloat problem, and illustrates the importance of
61 // having a small device queue, so that the standing queues build in the traffic
62 // control layer where they can be managed by advanced queue discs rather than
63 // in the device layer.
64 
65 using namespace ns3;
66 
67 NS_LOG_COMPONENT_DEFINE ("TrafficControlExample");
68 
69 void
TcPacketsInQueueTrace(uint32_t oldValue,uint32_t newValue)70 TcPacketsInQueueTrace (uint32_t oldValue, uint32_t newValue)
71 {
72   std::cout << "TcPacketsInQueue " << oldValue << " to " << newValue << std::endl;
73 }
74 
75 void
DevicePacketsInQueueTrace(uint32_t oldValue,uint32_t newValue)76 DevicePacketsInQueueTrace (uint32_t oldValue, uint32_t newValue)
77 {
78   std::cout << "DevicePacketsInQueue " << oldValue << " to " << newValue << std::endl;
79 }
80 
81 void
SojournTimeTrace(Time sojournTime)82 SojournTimeTrace (Time sojournTime)
83 {
84   std::cout << "Sojourn time " << sojournTime.ToDouble (Time::MS) << "ms" << std::endl;
85 }
86 
87 int
main(int argc,char * argv[])88 main (int argc, char *argv[])
89 {
90   double simulationTime = 10; //seconds
91   std::string transportProt = "Tcp";
92   std::string socketType;
93 
94   CommandLine cmd (__FILE__);
95   cmd.AddValue ("transportProt", "Transport protocol to use: Tcp, Udp", transportProt);
96   cmd.Parse (argc, argv);
97 
98   if (transportProt.compare ("Tcp") == 0)
99     {
100       socketType = "ns3::TcpSocketFactory";
101     }
102   else
103     {
104       socketType = "ns3::UdpSocketFactory";
105     }
106 
107   NodeContainer nodes;
108   nodes.Create (2);
109 
110   PointToPointHelper pointToPoint;
111   pointToPoint.SetDeviceAttribute ("DataRate", StringValue ("10Mbps"));
112   pointToPoint.SetChannelAttribute ("Delay", StringValue ("2ms"));
113   pointToPoint.SetQueue ("ns3::DropTailQueue", "MaxSize", StringValue ("1p"));
114 
115   NetDeviceContainer devices;
116   devices = pointToPoint.Install (nodes);
117 
118   InternetStackHelper stack;
119   stack.Install (nodes);
120 
121   TrafficControlHelper tch;
122   tch.SetRootQueueDisc ("ns3::RedQueueDisc");
123   QueueDiscContainer qdiscs = tch.Install (devices);
124 
125   Ptr<QueueDisc> q = qdiscs.Get (1);
126   q->TraceConnectWithoutContext ("PacketsInQueue", MakeCallback (&TcPacketsInQueueTrace));
127   Config::ConnectWithoutContext ("/NodeList/1/$ns3::TrafficControlLayer/RootQueueDiscList/0/SojournTime",
128                                  MakeCallback (&SojournTimeTrace));
129 
130   Ptr<NetDevice> nd = devices.Get (1);
131   Ptr<PointToPointNetDevice> ptpnd = DynamicCast<PointToPointNetDevice> (nd);
132   Ptr<Queue<Packet> > queue = ptpnd->GetQueue ();
133   queue->TraceConnectWithoutContext ("PacketsInQueue", MakeCallback (&DevicePacketsInQueueTrace));
134 
135   Ipv4AddressHelper address;
136   address.SetBase ("10.1.1.0", "255.255.255.0");
137 
138   Ipv4InterfaceContainer interfaces = address.Assign (devices);
139 
140   //Flow
141   uint16_t port = 7;
142   Address localAddress (InetSocketAddress (Ipv4Address::GetAny (), port));
143   PacketSinkHelper packetSinkHelper (socketType, localAddress);
144   ApplicationContainer sinkApp = packetSinkHelper.Install (nodes.Get (0));
145 
146   sinkApp.Start (Seconds (0.0));
147   sinkApp.Stop (Seconds (simulationTime + 0.1));
148 
149   uint32_t payloadSize = 1448;
150   Config::SetDefault ("ns3::TcpSocket::SegmentSize", UintegerValue (payloadSize));
151 
152   OnOffHelper onoff (socketType, Ipv4Address::GetAny ());
153   onoff.SetAttribute ("OnTime",  StringValue ("ns3::ConstantRandomVariable[Constant=1]"));
154   onoff.SetAttribute ("OffTime", StringValue ("ns3::ConstantRandomVariable[Constant=0]"));
155   onoff.SetAttribute ("PacketSize", UintegerValue (payloadSize));
156   onoff.SetAttribute ("DataRate", StringValue ("50Mbps")); //bit/s
157   ApplicationContainer apps;
158 
159   InetSocketAddress rmt (interfaces.GetAddress (0), port);
160   rmt.SetTos (0xb8);
161   AddressValue remoteAddress (rmt);
162   onoff.SetAttribute ("Remote", remoteAddress);
163   apps.Add (onoff.Install (nodes.Get (1)));
164   apps.Start (Seconds (1.0));
165   apps.Stop (Seconds (simulationTime + 0.1));
166 
167   FlowMonitorHelper flowmon;
168   Ptr<FlowMonitor> monitor = flowmon.InstallAll();
169 
170   Simulator::Stop (Seconds (simulationTime + 5));
171   Simulator::Run ();
172 
173   Ptr<Ipv4FlowClassifier> classifier = DynamicCast<Ipv4FlowClassifier> (flowmon.GetClassifier ());
174   std::map<FlowId, FlowMonitor::FlowStats> stats = monitor->GetFlowStats ();
175   std::cout << std::endl << "*** Flow monitor statistics ***" << std::endl;
176   std::cout << "  Tx Packets/Bytes:   " << stats[1].txPackets
177             << " / " << stats[1].txBytes << std::endl;
178   std::cout << "  Offered Load: " << stats[1].txBytes * 8.0 / (stats[1].timeLastTxPacket.GetSeconds () - stats[1].timeFirstTxPacket.GetSeconds ()) / 1000000 << " Mbps" << std::endl;
179   std::cout << "  Rx Packets/Bytes:   " << stats[1].rxPackets
180             << " / " << stats[1].rxBytes << std::endl;
181   uint32_t packetsDroppedByQueueDisc = 0;
182   uint64_t bytesDroppedByQueueDisc = 0;
183   if (stats[1].packetsDropped.size () > Ipv4FlowProbe::DROP_QUEUE_DISC)
184     {
185       packetsDroppedByQueueDisc = stats[1].packetsDropped[Ipv4FlowProbe::DROP_QUEUE_DISC];
186       bytesDroppedByQueueDisc = stats[1].bytesDropped[Ipv4FlowProbe::DROP_QUEUE_DISC];
187     }
188   std::cout << "  Packets/Bytes Dropped by Queue Disc:   " << packetsDroppedByQueueDisc
189             << " / " << bytesDroppedByQueueDisc << std::endl;
190   uint32_t packetsDroppedByNetDevice = 0;
191   uint64_t bytesDroppedByNetDevice = 0;
192   if (stats[1].packetsDropped.size () > Ipv4FlowProbe::DROP_QUEUE)
193     {
194       packetsDroppedByNetDevice = stats[1].packetsDropped[Ipv4FlowProbe::DROP_QUEUE];
195       bytesDroppedByNetDevice = stats[1].bytesDropped[Ipv4FlowProbe::DROP_QUEUE];
196     }
197   std::cout << "  Packets/Bytes Dropped by NetDevice:   " << packetsDroppedByNetDevice
198             << " / " << bytesDroppedByNetDevice << std::endl;
199   std::cout << "  Throughput: " << stats[1].rxBytes * 8.0 / (stats[1].timeLastRxPacket.GetSeconds () - stats[1].timeFirstRxPacket.GetSeconds ()) / 1000000 << " Mbps" << std::endl;
200   std::cout << "  Mean delay:   " << stats[1].delaySum.GetSeconds () / stats[1].rxPackets << std::endl;
201   std::cout << "  Mean jitter:   " << stats[1].jitterSum.GetSeconds () / (stats[1].rxPackets - 1) << std::endl;
202   auto dscpVec = classifier->GetDscpCounts (1);
203   for (auto p : dscpVec)
204     {
205       std::cout << "  DSCP value:   0x" << std::hex << static_cast<uint32_t> (p.first) << std::dec
206                 << "  count:   "<< p.second << std::endl;
207     }
208 
209   Simulator::Destroy ();
210 
211   std::cout << std::endl << "*** Application statistics ***" << std::endl;
212   double thr = 0;
213   uint64_t totalPacketsThr = DynamicCast<PacketSink> (sinkApp.Get (0))->GetTotalRx ();
214   thr = totalPacketsThr * 8 / (simulationTime * 1000000.0); //Mbit/s
215   std::cout << "  Rx Bytes: " << totalPacketsThr << std::endl;
216   std::cout << "  Average Goodput: " << thr << " Mbit/s" << std::endl;
217   std::cout << std::endl << "*** TC Layer statistics ***" << std::endl;
218   std::cout << q->GetStats () << std::endl;
219   return 0;
220 }
221