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.

Public Member Functions inherited from ns3::TcpGeneralTest
	TcpGeneralTest (const std::string &desc)
	TcpGeneralTest constructor.

	~TcpGeneralTest () override

Public Member Functions inherited from ns3::TestCase
	TestCase (const TestCase &)=delete

virtual	~TestCase ()
	Destructor.

std::string	GetName () const

TestCase &	operator= (const TestCase &)=delete

Protected Member Functions
void	ConfigureEnvironment () override
	Change the configuration of the environment.

void	ConfigureProperties () override
	Change the configuration of the socket properties.

void	CongStateTrace (const TcpSocketState::TcpCongState_t oldValue, const TcpSocketState::TcpCongState_t newValue) override
	State on Ack state machine changes.

Ptr< ErrorModel >	CreateReceiverErrorModel () override
	Create and return the error model to install in the receiver node.

void	FinalChecks () override
	Performs the (eventual) final checks through test asserts.

void	Rx (const Ptr< const Packet > p, const TcpHeader &h, SocketWho who) override
	Packet received from IP layer.

void	Tx (const Ptr< const Packet > p, const TcpHeader &h, SocketWho who) override
	Packet transmitted down to IP layer.

Protected Member Functions inherited from ns3::TcpGeneralTest
virtual void	AfterRTOExpired (const Ptr< const TcpSocketState > tcb, SocketWho who)
	Rto has expired.

virtual void	BeforeRTOExpired (const Ptr< const TcpSocketState > tcb, SocketWho who)
	Rto has expired.

virtual void	BytesInFlightTrace (uint32_t oldValue, uint32_t newValue)
	Bytes in flight changes.

virtual Ptr< SimpleChannel >	CreateChannel ()
	Create and return the channel installed between the two socket.

virtual Ptr< TcpSocketMsgBase >	CreateReceiverSocket (Ptr< Node > node)
	Create and install the socket to install on the receiver.

virtual Ptr< ErrorModel >	CreateSenderErrorModel ()
	Create and return the error model to install in the sender node.

virtual Ptr< TcpSocketMsgBase >	CreateSenderSocket (Ptr< Node > node)
	Create and install the socket to install on the sender.

virtual Ptr< TcpSocketMsgBase >	CreateSocket (Ptr< Node > node, TypeId socketType, TypeId congControl)
	Create a socket.

virtual Ptr< TcpSocketMsgBase >	CreateSocket (Ptr< Node > node, TypeId socketType, TypeId congControl, TypeId recoveryAlgorithm)
	Create a socket.

virtual void	CWndInflTrace (uint32_t oldValue, uint32_t newValue)
	Tracks the inflated congestion window changes.

virtual void	CWndTrace (uint32_t oldValue, uint32_t newValue)
	Tracks the congestion window changes.

virtual void	DataSent (uint32_t size, SocketWho who)
	Notifying application for sent data.

void	DoConnect ()
	Scheduled at 0.0, SENDER starts the connection to RECEIVER.

void	DoRun () override
	Execute the tcp test.

void	DoTeardown () override
	Teardown the TCP test.

virtual void	ErrorClose (SocketWho who)
	Socket closed with an error.

Time	GetClockGranularity (SocketWho who)
	Get the clock granularity attribute.

Time	GetConnTimeout (SocketWho who)
	Get the retransmission time for the SYN segments.

uint32_t	GetDelAckCount (SocketWho who)
	Get the number of delayed ack (if present)

Time	GetDelAckTimeout (SocketWho who)
	Get the timeout of delayed ack (if present)

uint32_t	GetDupAckCount (SocketWho who)
	Get the number of dupack received.

SequenceNumber32	GetHighestTxMark (SocketWho who)
	Get the highest tx mark of the node specified.

uint32_t	GetInitialCwnd (SocketWho who)
	Get the initial congestion window.

uint32_t	GetInitialSsThresh (SocketWho who)
	Get the initial slow start threshold.

Time	GetMinRto (SocketWho who)
	Get the minimum RTO attribute.

uint32_t	GetMtu () const
	Get the MTU of the environment.

EventId	GetPersistentEvent (SocketWho who)
	Get the persistent event of the selected socket.

Time	GetPersistentTimeout (SocketWho who)
	Get the persistent timeout of the selected socket.

uint32_t	GetPktCount () const
	Get the number of application packets.

Time	GetPktInterval () const
	Get the interval to wait for each packet sent down from application to TCP.

uint32_t	GetPktSize () const
	Get the application packet size.

Time	GetPropagationDelay () const
	Get the channel Propagation Delay.

Ptr< TcpSocketMsgBase >	GetReceiverSocket ()
	Get the pointer to a previously created receiver socket.

uint32_t	GetReTxThreshold (SocketWho who)
	Get the retransmission threshold.

Time	GetRto (SocketWho who)
	Get the retransmission time.

Ptr< RttEstimator >	GetRttEstimator (SocketWho who)
	Get the Rtt estimator of the socket.

uint32_t	GetRWnd (SocketWho who)
	Get the rWnd of the selected socket.

Ptr< TcpRxBuffer >	GetRxBuffer (SocketWho who)
	Get the Rx buffer from selected socket.

uint32_t	GetSegSize (SocketWho who)
	Get the segment size of the node specified.

Ptr< TcpSocketMsgBase >	GetSenderSocket ()
	Get the pointer to a previously created sender socket.

Time	GetStartTime () const
	Get the data start time.

Ptr< TcpSocketState >	GetTcb (SocketWho who)
	Get the TCB from selected socket.

TcpSocket::TcpStates_t	GetTcpState (SocketWho who)
	Get the state of the TCP state machine.

Ptr< TcpTxBuffer >	GetTxBuffer (SocketWho who)
	Get the Tx buffer from selected socket.

virtual void	HighestTxSeqTrace (SequenceNumber32 oldValue, SequenceNumber32 newValue)
	Highest tx seq changes.

virtual void	NextTxSeqTrace (SequenceNumber32 oldValue, SequenceNumber32 newValue)
	Next tx seq changes.

virtual void	NormalClose (SocketWho who)
	Socket closed normally.

virtual void	PhyDrop (SocketWho who)
	Link drop.

virtual void	ProcessedAck (const Ptr< const TcpSocketState > tcb, const TcpHeader &h, SocketWho who)
	Processed ack.

virtual void	QueueDrop (SocketWho who)
	Drop on the queue.

virtual void	RateSampleUpdatedTrace (const TcpRateLinux::TcpRateSample &sample)
	Track the rate sample value of TcpRateLinux.

virtual void	RateUpdatedTrace (const TcpRateLinux::TcpRateConnection &rate)
	Track the rate value of TcpRateLinux.

virtual void	RcvAck (const Ptr< const TcpSocketState > tcb, const TcpHeader &h, SocketWho who)
	Received ack.

virtual void	ReceivePacket (Ptr< Socket > socket)
	Packet received.

virtual void	RtoTrace (Time oldValue, Time newValue)
	RTO changes.

virtual void	RttTrace (Time oldTime, Time newTime)
	Rtt changes.

void	SendPacket (Ptr< Socket > socket, uint32_t pktSize, uint32_t pktCount, Time pktInterval)
	Send packets to other endpoint.

void	SetAppPktCount (uint32_t pktCount)
	Set app packet count.

void	SetAppPktInterval (Time pktInterval)
	Interval between app-generated packet.

void	SetAppPktSize (uint32_t pktSize)
	Set app packet size.

void	SetCongestionControl (TypeId congControl)
	Congestion control of the sender socket.

void	SetDelAckMaxCount (SocketWho who, uint32_t count)
	Forcefully set the delayed acknowledgement count.

void	SetInitialCwnd (SocketWho who, uint32_t initialCwnd)
	Forcefully set the initial cwnd.

void	SetInitialSsThresh (SocketWho who, uint32_t initialSsThresh)
	Forcefully set the initial ssthresh.

void	SetMTU (uint32_t mtu)
	MTU of the bottleneck link.

void	SetPaceInitialWindow (SocketWho who, bool paceWindow)
	Enable or disable pacing of the initial window.

void	SetPacingStatus (SocketWho who, bool pacing)
	Enable or disable pacing in the TCP socket.

void	SetPropagationDelay (Time propDelay)
	Propagation delay of the bottleneck link.

void	SetRcvBufSize (SocketWho who, uint32_t size)
	Forcefully set a defined size for rx buffer.

void	SetRecoveryAlgorithm (TypeId recovery)
	recovery algorithm of the sender socket

void	SetSegmentSize (SocketWho who, uint32_t segmentSize)
	Forcefully set the segment size.

void	SetTransmitStart (Time startTime)
	Set the initial time at which the application sends the first data packet.

void	SetUseEcn (SocketWho who, TcpSocketState::UseEcn_t useEcn)
	Forcefully set the ECN mode of use.

virtual void	SsThreshTrace (uint32_t oldValue, uint32_t newValue)
	Slow start threshold changes.

virtual void	UpdatedRttHistory (const SequenceNumber32 &seq, uint32_t sz, bool isRetransmission, SocketWho who)
	Updated the Rtt history.

Protected Member Functions inherited from ns3::TestCase
	TestCase (std::string name)
	Constructor.

void	AddTestCase (TestCase *testCase, Duration duration=Duration::QUICK)
	Add an individual child TestCase to this test suite.

TestCase *	GetParent () const
	Get the parent of this TestCase.

bool	IsStatusFailure () const
	Check if any tests failed.

bool	IsStatusSuccess () const
	Check if all tests passed.

void	SetDataDir (std::string directory)
	Set the data directory where reference trace files can be found.

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.

bool	MustAssertOnFailure () const
	Check if this run should assert on failure.

bool	MustContinueOnFailure () const
	Check if this run should continue on failure.

std::string	CreateDataDirFilename (std::string filename)
	Construct the full path to a file in the data directory.

std::string	CreateTempDirFilename (std::string filename)
	Construct the full path to a file in a temporary directory.

Private Attributes
std::list< int >	m_expectedStates
	Expected TCP states.

uint32_t	m_firstLoss
	First segment loss.

uint32_t	m_lastSegment {0}
	Last received segment.

uint32_t	m_received {0}
	Number of segments received.

uint32_t	m_secondLoss
	Second segment loss.

uint32_t	m_sent {0}
	Number of segments sent.

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 class	Duration { QUICK = 1 , EXTENSIVE = 2 , TAKES_FOREVER = 3 }
	How long the test takes to execute. More...

Static Public Attributes inherited from ns3::TestCase
static constexpr auto	QUICK = Duration::QUICK
	Deprecated test duration simple enums.

static constexpr auto	EXTENSIVE = Duration::EXTENSIVE

static constexpr auto	TAKES_FOREVER = Duration::TAKES_FOREVER

Protected Attributes inherited from ns3::TcpGeneralTest
TypeId	m_congControlTypeId
	Congestion control.

TypeId	m_recoveryTypeId
	Recovery.

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 43 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

firstLoss	First packet number to force loss
secondLoss	Second packet number to force loss
lastSegment	Last packet number to transmit
desc	Description about the test

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

References ns3::TcpSocketState::CA_DISORDER, ns3::TcpSocketState::CA_OPEN, ns3::TcpSocketState::CA_RECOVERY, 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 ( )

overrideprotectedvirtual

Change the configuration of the environment.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 111 of file tcp-loss-test.cc.

References ns3::TcpGeneralTest::ConfigureEnvironment(), m_lastSegment, ns3::MicroSeconds(), NS_LOG_FUNCTION, ns3::Seconds(), ns3::TcpGeneralTest::SetAppPktCount(), ns3::TcpGeneralTest::SetAppPktInterval(), ns3::TcpGeneralTest::SetAppPktSize(), ns3::TcpGeneralTest::SetPropagationDelay(), and ns3::TcpGeneralTest::SetTransmitStart().

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◆ ConfigureProperties()

void TcpLargeTransferLossTest::ConfigureProperties ( )

overrideprotectedvirtual

Change the configuration of the socket properties.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 125 of file tcp-loss-test.cc.

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

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◆ CongStateTrace()

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

overrideprotectedvirtual

State on Ack state machine changes.

Parameters

oldValue	old value
newValue	new value

Reimplemented from ns3::TcpGeneralTest.

Definition at line 101 of file tcp-loss-test.cc.

References m_expectedStates, and NS_TEST_ASSERT_MSG_EQ.

◆ CreateReceiverErrorModel()

Ptr< ErrorModel > TcpLargeTransferLossTest::CreateReceiverErrorModel ( )

overrideprotectedvirtual

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

Returns: receiver error model

Reimplemented from ns3::TcpGeneralTest.

Definition at line 134 of file tcp-loss-test.cc.

References ns3::CreateObject(), m_firstLoss, and m_secondLoss.

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◆ FinalChecks()

void TcpLargeTransferLossTest::FinalChecks ( )

overrideprotectedvirtual

Performs the (eventual) final checks through test asserts.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 157 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 )

overrideprotectedvirtual

Packet received from IP layer.

Parameters

p	packet
h	header
who	the socket which has received the packet (SENDER or RECEIVER)

Reimplemented from ns3::TcpGeneralTest.

Definition at line 151 of file tcp-loss-test.cc.

References m_received.

◆ Tx()

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

overrideprotectedvirtual

Packet transmitted down to IP layer.

Parameters

p	packet
h	header
who	the socket which has received the packet (SENDER or RECEIVER)

Reimplemented from ns3::TcpGeneralTest.

Definition at line 145 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 75 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 70 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 74 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 73 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 71 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 72 of file tcp-loss-test.cc.

Referenced by FinalChecks(), and Tx().

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

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

Public Member Functions

Protected Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ TcpLargeTransferLossTest()

Member Function Documentation

◆ ConfigureEnvironment()

◆ ConfigureProperties()

◆ CongStateTrace()

◆ CreateReceiverErrorModel()

◆ FinalChecks()

◆ Rx()

◆ Tx()

Member Data Documentation

◆ m_expectedStates

◆ m_firstLoss

◆ m_lastSegment

◆ m_received

◆ m_secondLoss

◆ m_sent