A Discrete-Event Network Simulator
API
TcpLargeTransferLossTest Class Reference

Check rollover of sequence number and how that affects loss recovery. More...

+ Inheritance diagram for TcpLargeTransferLossTest:
+ Collaboration diagram for TcpLargeTransferLossTest:

Public Member Functions

 TcpLargeTransferLossTest (uint32_t firstLoss, uint32_t secondLoss, uint32_t lastSegment, const std::string &desc)
 Constructor. More...
 
- Public Member Functions inherited from ns3::TcpGeneralTest
 TcpGeneralTest (const std::string &desc)
 TcpGeneralTest constructor. More...
 
 ~TcpGeneralTest ()
 
- Public Member Functions inherited from ns3::TestCase
 TestCase (const TestCase &)=delete
 
virtual ~TestCase ()
 Destructor. More...
 
std::string GetName (void) const
 
TestCaseoperator= (const TestCase &)=delete
 

Protected Member Functions

void ConfigureEnvironment (void)
 Change the configuration of the environment. More...
 
void ConfigureProperties (void)
 Change the configuration of the socket properties. More...
 
void CongStateTrace (const TcpSocketState::TcpCongState_t oldValue, const TcpSocketState::TcpCongState_t newValue)
 
Ptr< ErrorModelCreateReceiverErrorModel ()
 Create and return the error model to install in the receiver node. More...
 
void FinalChecks (void)
 Performs the (eventual) final checks through test asserts. More...
 
void Rx (const Ptr< const Packet > p, const TcpHeader &h, SocketWho who)
 Packet received from IP layer. More...
 
void Tx (const Ptr< const Packet > p, const TcpHeader &h, SocketWho who)
 Packet transmitted down to IP layer. More...
 
- Protected Member Functions inherited from ns3::TcpGeneralTest
virtual void AfterRTOExpired ([[maybe_unused]] const Ptr< const TcpSocketState > tcb, [[maybe_unused]] SocketWho who)
 Rto has expired. More...
 
virtual void BeforeRTOExpired ([[maybe_unused]] const Ptr< const TcpSocketState > tcb, [[maybe_unused]] SocketWho who)
 Rto has expired. More...
 
virtual void BytesInFlightTrace ([[maybe_unused]] uint32_t oldValue, [[maybe_unused]] uint32_t newValue)
 Bytes in flight changes. More...
 
virtual void CongStateTrace ([[maybe_unused]] const TcpSocketState::TcpCongState_t oldValue, [[maybe_unused]] const TcpSocketState::TcpCongState_t newValue)
 State on Ack state machine changes. More...
 
virtual Ptr< SimpleChannelCreateChannel ()
 Create and return the channel installed between the two socket. More...
 
virtual Ptr< TcpSocketMsgBaseCreateReceiverSocket (Ptr< Node > node)
 Create and install the socket to install on the receiver. More...
 
virtual Ptr< ErrorModelCreateSenderErrorModel ()
 Create and return the error model to install in the sender node. More...
 
virtual Ptr< TcpSocketMsgBaseCreateSenderSocket (Ptr< Node > node)
 Create and install the socket to install on the sender. More...
 
virtual Ptr< TcpSocketMsgBaseCreateSocket (Ptr< Node > node, TypeId socketType, TypeId congControl)
 Create a socket. More...
 
virtual Ptr< TcpSocketMsgBaseCreateSocket (Ptr< Node > node, TypeId socketType, TypeId congControl, TypeId recoveryAlgorithm)
 Create a socket. More...
 
virtual void CWndInflTrace ([[maybe_unused]] uint32_t oldValue, [[maybe_unused]] uint32_t newValue)
 Tracks the inflated congestion window changes. More...
 
virtual void CWndTrace ([[maybe_unused]] uint32_t oldValue, [[maybe_unused]] uint32_t newValue)
 Tracks the congestion window changes. More...
 
virtual void DataSent ([[maybe_unused]] uint32_t size, [[maybe_unused]] SocketWho who)
 Notifying application for sent data. More...
 
void DoConnect ()
 Scheduled at 0.0, SENDER starts the connection to RECEIVER. More...
 
virtual void DoRun (void)
 Execute the tcp test. More...
 
virtual void DoTeardown (void)
 Teardown the TCP test. More...
 
virtual void ErrorClose ([[maybe_unused]] SocketWho who)
 Socket closed with an error. More...
 
Time GetClockGranularity (SocketWho who)
 Get the clock granularity attribute. More...
 
Time GetConnTimeout (SocketWho who)
 Get the retransmission time for the SYN segments. More...
 
uint32_t GetDelAckCount (SocketWho who)
 Get the number of delayed ack (if present) More...
 
Time GetDelAckTimeout (SocketWho who)
 Get the timeout of delayed ack (if present) More...
 
uint32_t GetDupAckCount (SocketWho who)
 Get the number of dupack received. More...
 
SequenceNumber32 GetHighestTxMark (SocketWho who)
 Get the highest tx mark of the node specified. More...
 
uint32_t GetInitialCwnd (SocketWho who)
 Get the initial congestion window. More...
 
uint32_t GetInitialSsThresh (SocketWho who)
 Get the initial slow start threshold. More...
 
Time GetMinRto (SocketWho who)
 Get the minimum RTO attribute. More...
 
uint32_t GetMtu () const
 Get the MTU of the environment. More...
 
EventId GetPersistentEvent (SocketWho who)
 Get the persistent event of the selected socket. More...
 
Time GetPersistentTimeout (SocketWho who)
 Get the persistent timeout of the selected socket. More...
 
uint32_t GetPktCount () const
 Get the number of application packets. More...
 
Time GetPktInterval () const
 Get the interval to wait for each packet sent down from application to TCP. More...
 
uint32_t GetPktSize () const
 Get the application packet size. More...
 
Time GetPropagationDelay () const
 Get the channel Propagation Delay. More...
 
Ptr< TcpSocketMsgBaseGetReceiverSocket ()
 Get the pointer to a previously created receiver socket. More...
 
uint32_t GetReTxThreshold (SocketWho who)
 Get the retransmission threshold. More...
 
Time GetRto (SocketWho who)
 Get the retransmission time. More...
 
Ptr< RttEstimatorGetRttEstimator (SocketWho who)
 Get the Rtt estimator of the socket. More...
 
uint32_t GetRWnd (SocketWho who)
 Get the rWnd of the selected socket. More...
 
Ptr< TcpRxBufferGetRxBuffer (SocketWho who)
 Get the Rx buffer from selected socket. More...
 
uint32_t GetSegSize (SocketWho who)
 Get the segment size of the node specified. More...
 
Ptr< TcpSocketMsgBaseGetSenderSocket ()
 Get the pointer to a previously created sender socket. More...
 
Time GetStartTime () const
 Get the data start time. More...
 
Ptr< TcpSocketStateGetTcb (SocketWho who)
 Get the TCB from selected socket. More...
 
TcpSocket::TcpStates_t GetTcpState (SocketWho who)
 Get the state of the TCP state machine. More...
 
Ptr< TcpTxBufferGetTxBuffer (SocketWho who)
 Get the Tx buffer from selected socket. More...
 
virtual void HighestTxSeqTrace ([[maybe_unused]] SequenceNumber32 oldValue, [[maybe_unused]] SequenceNumber32 newValue)
 Highest tx seq changes. More...
 
virtual void NextTxSeqTrace ([[maybe_unused]] SequenceNumber32 oldValue, [[maybe_unused]] SequenceNumber32 newValue)
 Next tx seq changes. More...
 
virtual void NormalClose ([[maybe_unused]] SocketWho who)
 Socket closed normally. More...
 
virtual void PhyDrop ([[maybe_unused]] SocketWho who)
 Link drop. More...
 
virtual void ProcessedAck ([[maybe_unused]] const Ptr< const TcpSocketState > tcb, [[maybe_unused]] const TcpHeader &h, [[maybe_unused]] SocketWho who)
 Processed ack. More...
 
virtual void QueueDrop ([[maybe_unused]] SocketWho who)
 Drop on the queue. More...
 
virtual void RateSampleUpdatedTrace ([[maybe_unused]] const TcpRateLinux::TcpRateSample &sample)
 Track the rate sample value of TcpRateLinux. More...
 
virtual void RateUpdatedTrace ([[maybe_unused]] const TcpRateLinux::TcpRateConnection &rate)
 Track the rate value of TcpRateLinux. More...
 
virtual void RcvAck ([[maybe_unused]] const Ptr< const TcpSocketState > tcb, [[maybe_unused]] const TcpHeader &h, [[maybe_unused]] SocketWho who)
 Received ack. More...
 
virtual void ReceivePacket (Ptr< Socket > socket)
 Packet received. More...
 
virtual void RtoTrace ([[maybe_unused]] Time oldValue, [[maybe_unused]] Time newValue)
 RTO changes. More...
 
virtual void RttTrace ([[maybe_unused]] Time oldTime, [[maybe_unused]] Time newTime)
 Rtt changes. More...
 
void SendPacket (Ptr< Socket > socket, uint32_t pktSize, uint32_t pktCount, Time pktInterval)
 Send packets to other endpoint. More...
 
void SetAppPktCount (uint32_t pktCount)
 Set app packet count. More...
 
void SetAppPktInterval (Time pktInterval)
 Interval between app-generated packet. More...
 
void SetAppPktSize (uint32_t pktSize)
 Set app packet size. More...
 
void SetCongestionControl (TypeId congControl)
 Congestion control of the sender socket. More...
 
void SetDelAckMaxCount (SocketWho who, uint32_t count)
 Forcefully set the delayed acknowledgement count. More...
 
void SetInitialCwnd (SocketWho who, uint32_t initialCwnd)
 Forcefully set the initial cwnd. More...
 
void SetInitialSsThresh (SocketWho who, uint32_t initialSsThresh)
 Forcefully set the initial ssthresh. More...
 
void SetMTU (uint32_t mtu)
 MTU of the bottleneck link. More...
 
void SetPaceInitialWindow (SocketWho who, bool paceWindow)
 Enable or disable pacing of the initial window. More...
 
void SetPacingStatus (SocketWho who, bool pacing)
 Enable or disable pacing in the TCP socket. More...
 
void SetPropagationDelay (Time propDelay)
 Propagation delay of the bottleneck link. More...
 
void SetRcvBufSize (SocketWho who, uint32_t size)
 Forcefully set a defined size for rx buffer. More...
 
void SetRecoveryAlgorithm (TypeId recovery)
 recovery algorithm of the sender socket More...
 
void SetSegmentSize (SocketWho who, uint32_t segmentSize)
 Forcefully set the segment size. More...
 
void SetTransmitStart (Time startTime)
 Set the initial time at which the application sends the first data packet. More...
 
void SetUseEcn (SocketWho who, TcpSocketState::UseEcn_t useEcn)
 Forcefully set the ECN mode of use. More...
 
virtual void SsThreshTrace ([[maybe_unused]] uint32_t oldValue, [[maybe_unused]] uint32_t newValue)
 Slow start threshold changes. More...
 
virtual void UpdatedRttHistory ([[maybe_unused]] const SequenceNumber32 &seq, [[maybe_unused]] uint32_t sz, [[maybe_unused]] bool isRetransmission, [[maybe_unused]] SocketWho who)
 Updated the Rtt history. More...
 
- Protected Member Functions inherited from ns3::TestCase
 TestCase (std::string name)
 Constructor. More...
 
void AddTestCase (TestCase *testCase, TestDuration duration=QUICK)
 Add an individual child TestCase to this test suite. More...
 
TestCaseGetParent () const
 Get the parent of this TestCsse. More...
 
bool IsStatusFailure (void) const
 Check if any tests failed. More...
 
bool IsStatusSuccess (void) const
 Check if all tests passed. More...
 
void SetDataDir (std::string directory)
 Set the data directory where reference trace files can be found. More...
 
void ReportTestFailure (std::string cond, std::string actual, std::string limit, std::string message, std::string file, int32_t line)
 Log the failure of this TestCase. More...
 
bool MustAssertOnFailure (void) const
 Check if this run should assert on failure. More...
 
bool MustContinueOnFailure (void) const
 Check if this run should continue on failure. More...
 
std::string CreateDataDirFilename (std::string filename)
 Construct the full path to a file in the data directory. More...
 
std::string CreateTempDirFilename (std::string filename)
 Construct the full path to a file in a temporary directory. More...
 

Private Attributes

std::list< int > m_expectedStates
 Expected TCP states. More...
 
uint32_t m_firstLoss
 First segment loss. More...
 
uint32_t m_lastSegment {0}
 Last received segment. More...
 
uint32_t m_received {0}
 Number of segments received. More...
 
uint32_t m_secondLoss
 Second segment loss. More...
 
uint32_t m_sent {0}
 Number of segments sent. More...
 

Additional Inherited Members

- Public Types inherited from ns3::TcpGeneralTest
enum  SocketWho { SENDER , RECEIVER }
 Used as parameter of methods, specifies on what node the caller is interested (e.g. More...
 
- Public Types inherited from ns3::TestCase
enum  TestDuration { QUICK = 1 , EXTENSIVE = 2 , TAKES_FOREVER = 3 }
 How long the test takes to execute. More...
 
- Protected Attributes inherited from ns3::TcpGeneralTest
TypeId m_congControlTypeId
 Congestion control. More...
 
TypeId m_recoveryTypeId
 Recovery. More...
 

Detailed Description

Check rollover of sequence number and how that affects loss recovery.

This test checks that fast recovery is entered correctly even if it has been a long time since the last recovery event. Merge request !156 reported the error and fixed the issue with large transfers.

The issue reported is that fast recovery detection relies on comparing the sequence number against the last recovery point, maintained by an 'm_recover' variable. The sequence number is a 32-bit value that wraps, so the comparison of 'is current sequence number > m_recover' will work for only about half of the 32-bit sequence space. This test confirms that the above inequality will correctly evaluate even if the current sequence number is greater than half of the sequence space above m_recover.

The test configures a large bandwidth, long flow (to wrap the sequence space) and inserts two forced losses. In the first test case, the two sequence numbers are close in sequence; we expect to see the TCP implementation cycle between CA_OPEN->CA_DISORDER->CA_RECOVERY->CA_OPEN. We also check in the second case when the two sequence numbers are far apart (more than half) in the sequence space.

Definition at line 54 of file tcp-loss-test.cc.

Constructor & Destructor Documentation

◆ TcpLargeTransferLossTest()

TcpLargeTransferLossTest::TcpLargeTransferLossTest ( uint32_t  firstLoss,
uint32_t  secondLoss,
uint32_t  lastSegment,
const std::string &  desc 
)

Constructor.

Parameters
firstLossFirst packet number to force loss
secondLossSecond packet number to force loss
lastSegmentLast packet number to transmit
descDescription about the test

Definition at line 85 of file tcp-loss-test.cc.

References m_expectedStates, m_firstLoss, m_lastSegment, m_secondLoss, NS_TEST_ASSERT_MSG_GT, and NS_TEST_ASSERT_MSG_NE.

Member Function Documentation

◆ ConfigureEnvironment()

void TcpLargeTransferLossTest::ConfigureEnvironment ( void  )
protectedvirtual

◆ ConfigureProperties()

void TcpLargeTransferLossTest::ConfigureProperties ( void  )
protectedvirtual

Change the configuration of the socket properties.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 127 of file tcp-loss-test.cc.

References NS_LOG_FUNCTION, ns3::TcpGeneralTest::RECEIVER, ns3::TcpGeneralTest::SENDER, and ns3::TcpGeneralTest::SetSegmentSize().

+ Here is the call graph for this function:

◆ CongStateTrace()

void TcpLargeTransferLossTest::CongStateTrace ( const TcpSocketState::TcpCongState_t  oldValue,
const TcpSocketState::TcpCongState_t  newValue 
)
protected

Definition at line 103 of file tcp-loss-test.cc.

References m_expectedStates, and NS_TEST_ASSERT_MSG_EQ.

◆ CreateReceiverErrorModel()

Ptr< ErrorModel > TcpLargeTransferLossTest::CreateReceiverErrorModel ( )
protectedvirtual

Create and return the error model to install in the receiver node.

Returns
receiver error model

Reimplemented from ns3::TcpGeneralTest.

Definition at line 136 of file tcp-loss-test.cc.

References m_firstLoss, and m_secondLoss.

◆ FinalChecks()

void TcpLargeTransferLossTest::FinalChecks ( void  )
protectedvirtual

Performs the (eventual) final checks through test asserts.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 159 of file tcp-loss-test.cc.

References m_received, m_sent, and NS_TEST_ASSERT_MSG_EQ.

◆ Rx()

void TcpLargeTransferLossTest::Rx ( const Ptr< const Packet p,
const TcpHeader h,
SocketWho  who 
)
protectedvirtual

Packet received from IP layer.

Parameters
ppacket
hheader
whothe socket which has received the packet (SENDER or RECEIVER)

Reimplemented from ns3::TcpGeneralTest.

Definition at line 153 of file tcp-loss-test.cc.

References m_received.

◆ Tx()

void TcpLargeTransferLossTest::Tx ( const Ptr< const Packet p,
const TcpHeader h,
SocketWho  who 
)
protectedvirtual

Packet transmitted down to IP layer.

Parameters
ppacket
hheader
whothe socket which has received the packet (SENDER or RECEIVER)

Reimplemented from ns3::TcpGeneralTest.

Definition at line 147 of file tcp-loss-test.cc.

References m_sent.

Member Data Documentation

◆ m_expectedStates

std::list<int> TcpLargeTransferLossTest::m_expectedStates
private

Expected TCP states.

Definition at line 82 of file tcp-loss-test.cc.

Referenced by TcpLargeTransferLossTest(), and CongStateTrace().

◆ m_firstLoss

uint32_t TcpLargeTransferLossTest::m_firstLoss
private

First segment loss.

Definition at line 77 of file tcp-loss-test.cc.

Referenced by TcpLargeTransferLossTest(), and CreateReceiverErrorModel().

◆ m_lastSegment

uint32_t TcpLargeTransferLossTest::m_lastSegment {0}
private

Last received segment.

Definition at line 81 of file tcp-loss-test.cc.

Referenced by TcpLargeTransferLossTest(), and ConfigureEnvironment().

◆ m_received

uint32_t TcpLargeTransferLossTest::m_received {0}
private

Number of segments received.

Definition at line 80 of file tcp-loss-test.cc.

Referenced by FinalChecks(), and Rx().

◆ m_secondLoss

uint32_t TcpLargeTransferLossTest::m_secondLoss
private

Second segment loss.

Definition at line 78 of file tcp-loss-test.cc.

Referenced by TcpLargeTransferLossTest(), and CreateReceiverErrorModel().

◆ m_sent

uint32_t TcpLargeTransferLossTest::m_sent {0}
private

Number of segments sent.

Definition at line 79 of file tcp-loss-test.cc.

Referenced by FinalChecks(), and Tx().


The documentation for this class was generated from the following file: