1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3 * Copyright (c) 2018 NITK Surathkal
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 * Authors: Vivek Jain <jain.vivek.anand@gmail.com>
19 * Viyom Mittal <viyommittal@gmail.com>
20 * Mohit P. Tahiliani <tahiliani@nitk.edu.in>
21 *
22 */
23
24 #include "ns3/test.h"
25 #include "ns3/log.h"
26 #include "ns3/tcp-congestion-ops.h"
27 #include "ns3/tcp-socket-base.h"
28 #include "ns3/tcp-bbr.h"
29
30 namespace ns3 {
31
32 NS_LOG_COMPONENT_DEFINE ("TcpBbrTestSuite");
33
34 /**
35 * \brief Testing whether BBR enables pacing
36 */
37 class TcpBbrPacingEnableTest : public TestCase
38 {
39 public:
40 /**
41 * \brief constructor
42 * \param pacing pacing configuration
43 * \param name description of the test
44 */
45 TcpBbrPacingEnableTest (bool pacing, const std::string &name);
46
47 private:
48 virtual void DoRun (void);
49 /**
50 * \brief Execute the test.
51 */
52 void ExecuteTest (void);
53 bool m_pacing; //!< Initial pacing configuration.
54 };
55
TcpBbrPacingEnableTest(bool pacing,const std::string & name)56 TcpBbrPacingEnableTest::TcpBbrPacingEnableTest (bool pacing, const std::string &name)
57 : TestCase (name),
58 m_pacing (pacing)
59 {}
60
61 void
DoRun()62 TcpBbrPacingEnableTest::DoRun ()
63 {
64 Simulator::Schedule (Seconds (0.0), &TcpBbrPacingEnableTest::ExecuteTest, this);
65 Simulator::Run ();
66 Simulator::Destroy ();
67 }
68
69 void
ExecuteTest()70 TcpBbrPacingEnableTest::ExecuteTest ()
71 {
72 Ptr<TcpSocketState> state = CreateObject <TcpSocketState> ();
73 state->m_pacing = m_pacing;
74
75 Ptr<TcpBbr> cong = CreateObject <TcpBbr> ();
76
77 cong->CongestionStateSet (state, TcpSocketState::CA_OPEN);
78
79 NS_TEST_ASSERT_MSG_EQ (state->m_pacing, true,
80 "BBR has not updated pacing value");
81 }
82
83 /**
84 * \brief Tests whether BBR sets correct value of pacing and cwnd gain based on different state.
85 */
86 class TcpBbrCheckGainValuesTest : public TestCase
87 {
88 public:
89 /**
90 * \brief constructor
91 * \param state BBR state/mode under test
92 * \param highGain value of pacing and cwnd gain
93 * \param name description of the test
94 */
95 TcpBbrCheckGainValuesTest (TcpBbr::BbrMode_t state, double highGain, const std::string &name);
96
97 private:
98 virtual void DoRun (void);
99 /**
100 * \brief Execute the test.
101 */
102 void ExecuteTest (void);
103 TcpBbr::BbrMode_t m_mode; //!< BBR mode under test
104 double m_highGain; //!< Value of BBR high gain
105 };
106
TcpBbrCheckGainValuesTest(TcpBbr::BbrMode_t state,double highGain,const std::string & name)107 TcpBbrCheckGainValuesTest::TcpBbrCheckGainValuesTest (TcpBbr::BbrMode_t state,
108 double highGain, const std::string &name)
109 : TestCase (name),
110 m_mode (state),
111 m_highGain (highGain)
112 {}
113
114 void
DoRun()115 TcpBbrCheckGainValuesTest::DoRun ()
116 {
117 Simulator::Schedule (Seconds (0.0), &TcpBbrCheckGainValuesTest::ExecuteTest, this);
118 Simulator::Run ();
119 Simulator::Destroy ();
120 }
121
122 void
ExecuteTest()123 TcpBbrCheckGainValuesTest::ExecuteTest ()
124 {
125 Ptr<TcpBbr> cong = CreateObject <TcpBbr> ();
126 cong->SetAttribute ("HighGain", DoubleValue (m_highGain));
127 double actualPacingGain, actualCwndGain, desiredPacingGain = m_highGain, desiredCwndGain = m_highGain;
128 TcpBbr::BbrMode_t desiredMode = TcpBbr::BBR_STARTUP;
129 switch (m_mode)
130 {
131 case TcpBbr::BBR_STARTUP:
132 cong->EnterStartup ();
133 desiredPacingGain = m_highGain;
134 desiredCwndGain = m_highGain;
135 actualPacingGain = cong->GetPacingGain ();
136 actualCwndGain = cong->GetCwndGain ();
137 desiredMode = TcpBbr::BBR_STARTUP;
138 break;
139 case TcpBbr::BBR_DRAIN:
140 cong->EnterDrain ();
141 desiredPacingGain = 1 / m_highGain;
142 desiredCwndGain = m_highGain;
143 desiredMode = TcpBbr::BBR_DRAIN;
144 break;
145 case TcpBbr::BBR_PROBE_BW:
146 cong->EnterProbeBW ();
147 // The value of desiredPacingGain is sensitive to the setting of random
148 // variable stream. The value of 1.25 has been used in this test with a
149 // stream value of 4 (default for TCP BBR). Note that if the stream value
150 // is changed, this test might fail because when BBR enters the PROBE_BW
151 // phase, the value of actualPacingGain is chosen randomly from 1.25,
152 // 0.75, 1, 1, 1, 1, 1, 1.
153 desiredPacingGain = 1.25;
154 desiredCwndGain = 2;
155 desiredMode = TcpBbr::BBR_PROBE_BW;
156 break;
157 case TcpBbr::BBR_PROBE_RTT:
158 cong->EnterProbeRTT ();
159 desiredPacingGain = 1;
160 desiredCwndGain = 1;
161 desiredMode = TcpBbr::BBR_PROBE_RTT;
162 break;
163 default:
164 NS_ASSERT (false);
165 }
166
167 actualPacingGain = cong->GetPacingGain ();
168 actualCwndGain = cong->GetCwndGain ();
169 NS_TEST_ASSERT_MSG_EQ (m_mode, desiredMode, "BBR has not entered into desired state");
170 NS_TEST_ASSERT_MSG_EQ (actualPacingGain, desiredPacingGain, "BBR has not updated into desired pacing gain");
171 NS_TEST_ASSERT_MSG_EQ (actualCwndGain, desiredCwndGain, "BBR has not updated into desired cwnd gain");
172 }
173
174 /**
175 * \ingroup internet-test
176 * \ingroup tests
177 *
178 * \brief TCP BBR TestSuite
179 */
180 class TcpBbrTestSuite : public TestSuite
181 {
182 public:
183 /**
184 * \brief constructor
185 */
TcpBbrTestSuite()186 TcpBbrTestSuite () : TestSuite ("tcp-bbr-test", UNIT)
187 {
188 AddTestCase (new TcpBbrPacingEnableTest (true, "BBR must keep pacing feature on"), TestCase::QUICK);
189
190 AddTestCase (new TcpBbrPacingEnableTest (false, "BBR must turn on pacing feature"), TestCase::QUICK);
191
192 AddTestCase (new TcpBbrCheckGainValuesTest (TcpBbr::BBR_STARTUP, 4, "BBR should enter to STARTUP phase and set cwnd and pacing gain accordingly"), TestCase::QUICK);
193
194 AddTestCase (new TcpBbrCheckGainValuesTest (TcpBbr::BBR_DRAIN, 4, "BBR should enter to DRAIN phase and set cwnd and pacing gain accordingly"), TestCase::QUICK);
195
196 AddTestCase (new TcpBbrCheckGainValuesTest (TcpBbr::BBR_PROBE_BW, 4, "BBR should enter to BBR_PROBE_BW phase and set cwnd and pacing gain accordingly"), TestCase::QUICK);
197
198 AddTestCase (new TcpBbrCheckGainValuesTest (TcpBbr::BBR_PROBE_RTT, 4, "BBR should enter to BBR_PROBE_RTT phase and set cwnd and pacing gain accordingly"), TestCase::QUICK);
199 }
200 };
201
202 static TcpBbrTestSuite g_tcpBbrTest; //!< static variable for test initialization
203 }
204