tcp: Add BBR test suite

src/internet/test/tcp-bbr-test.cc

@@ -0,0 +1,172 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2018 NITK Surathkal
+ *
+ * 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
+ *
+ * Authors: Vivek Jain <jain.vivek.anand@gmail.com>
+ *          Viyom Mittal <viyommittal@gmail.com>
+ *          Mohit P. Tahiliani <tahiliani@nitk.edu.in>
+ *
+ */
+
+#include "ns3/test.h"
+#include "ns3/log.h"
+#include "ns3/tcp-congestion-ops.h"
+#include "ns3/tcp-socket-base.h"
+#include "ns3/tcp-bbr.h"
+
+namespace ns3 {
+
+NS_LOG_COMPONENT_DEFINE ("TcpBbrTestSuite");
+
+/**
+ * \brief Testing whether BBR enables pacing
+ */
+class TcpBbrPacingEnableTest : public TestCase
+{
+public:
+  TcpBbrPacingEnableTest (bool pacing, const std::string &name);
+
+private:
+  virtual void DoRun (void);
+  void ExecuteTest (void);
+  bool m_pacing;
+};
+
+TcpBbrPacingEnableTest::TcpBbrPacingEnableTest (bool pacing, const std::string &name)
+  : TestCase (name),
+    m_pacing (pacing)
+{
+}
+
+void
+TcpBbrPacingEnableTest::DoRun ()
+{
+  Simulator::Schedule (Seconds (0.0), &TcpBbrPacingEnableTest::ExecuteTest, this);
+  Simulator::Run ();
+  Simulator::Destroy ();
+}
+
+void
+TcpBbrPacingEnableTest::ExecuteTest ()
+{
+  Ptr<TcpSocketState> state = CreateObject <TcpSocketState> ();
+  state->m_pacing = m_pacing;
+
+  Ptr<TcpBbr> cong = CreateObject <TcpBbr> ();
+
+  cong->CongestionStateSet (state, TcpSocketState::CA_OPEN);
+
+  NS_TEST_ASSERT_MSG_EQ (state->m_pacing, true,
+                         "BBR has not updated pacing value");
+}
+
+/**
+ * \brief Tests whether BBR sets correct value of pacing and cwnd gain based on different state.
+ */
+class TcpBbrCheckGainValuesTest : public TestCase
+{
+public:
+  TcpBbrCheckGainValuesTest (TcpBbr::BbrMode_t state, double highGain, const std::string &name);
+
+private:
+  virtual void DoRun (void);
+  void ExecuteTest (void);
+  TcpBbr::BbrMode_t m_mode;
+  double m_highGain;
+};
+
+TcpBbrCheckGainValuesTest::TcpBbrCheckGainValuesTest (TcpBbr::BbrMode_t state,
+                                                      double highGain, const std::string &name)
+  : TestCase (name),
+    m_mode (state),
+    m_highGain (highGain)
+{
+}
+
+void
+TcpBbrCheckGainValuesTest::DoRun ()
+{
+  Simulator::Schedule (Seconds (0.0), &TcpBbrCheckGainValuesTest::ExecuteTest, this);
+  Simulator::Run ();
+  Simulator::Destroy ();
+}
+
+void
+TcpBbrCheckGainValuesTest::ExecuteTest ()
+{
+  Ptr<TcpBbr> cong = CreateObject <TcpBbr> ();
+  cong->SetAttribute ("HighGain", DoubleValue (m_highGain));
+  double actualPacingGain, actualCwndGain, desiredPacingGain, desiredCwndGain;
+  TcpBbr::BbrMode_t desiredMode;
+  switch (m_mode)
+    {
+    case TcpBbr::BBR_STARTUP:
+      cong->EnterStartup ();
+      desiredPacingGain = m_highGain;
+      desiredCwndGain  = m_highGain;
+      actualPacingGain = cong->GetPacingGain ();
+      actualCwndGain = cong->GetCwndGain ();
+      desiredMode = TcpBbr::BBR_STARTUP;
+      break;
+    case TcpBbr::BBR_DRAIN:
+      cong->EnterDrain ();
+      desiredPacingGain = 1 / m_highGain;
+      desiredCwndGain  = m_highGain;
+      desiredMode = TcpBbr::BBR_DRAIN;
+      break;
+    case TcpBbr::BBR_PROBE_BW:
+      cong->EnterProbeBW ();
+      desiredPacingGain = 1;
+      desiredCwndGain  = 2;
+      desiredMode = TcpBbr::BBR_PROBE_BW;
+      break;
+    case TcpBbr::BBR_PROBE_RTT:
+      cong->EnterProbeRTT ();
+      desiredPacingGain = 1;
+      desiredCwndGain  = 1;
+      desiredMode = TcpBbr::BBR_PROBE_RTT;
+      break;
+    default:
+      NS_ASSERT (false);
+    }
+
+  actualPacingGain = cong->GetPacingGain ();
+  actualCwndGain = cong->GetCwndGain ();
+  NS_TEST_ASSERT_MSG_EQ (m_mode, desiredMode, "BBR has not entered into desired state");
+  NS_TEST_ASSERT_MSG_EQ (actualPacingGain, desiredPacingGain, "BBR has not updated into desired pacing gain");
+  NS_TEST_ASSERT_MSG_EQ (actualCwndGain, desiredCwndGain, "BBR has not updated into desired cwnd gain");
+}
+
+static class TcpBbrTestSuite : public TestSuite
+{
+public:
+  TcpBbrTestSuite () : TestSuite ("tcp-bbr-test", UNIT)
+  {
+    AddTestCase (new TcpBbrPacingEnableTest (true, "BBR must keep pacing feature on"), TestCase::QUICK);
+
+    AddTestCase (new TcpBbrPacingEnableTest (false, "BBR must turn on pacing feature"), TestCase::QUICK);
+
+    AddTestCase (new TcpBbrCheckGainValuesTest (TcpBbr::BBR_STARTUP, 4, "BBR should enter to STARTUP phase and set cwnd and pacing gain accordingly"), TestCase::QUICK);
+
+    AddTestCase (new TcpBbrCheckGainValuesTest (TcpBbr::BBR_DRAIN, 4, "BBR should enter to DRAIN phase and set cwnd and pacing gain accordingly"), TestCase::QUICK);
+
+    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);
+
+    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);
+  }
+} g_tcpBbrTest;
+
+}

src/internet/wscript

@@ -308,6 +308,7 @@ def build(bld):
         'test/tcp-dctcp-test.cc',
         'test/tcp-syn-connection-failed-test.cc',
         'test/tcp-pacing-test.cc',
+        'test/tcp-bbr-test.cc',
         ]
     # Tests encapsulating example programs should be listed here
     if (bld.env['ENABLE_EXAMPLES']):