This unit test checks that the slow start and congestion avoidance behavior matches Linux behavior as follows: 1) in both slow start and congestion avoidance phases, presence or absence of delayed acks does not alter the window growth 2) in congestion avoidance phase, the arithmetic for counting the number of segments acked and deciding when to increment the congestion window (i.e. More...

Inheritance diagram for TcpLinuxRenoCongAvoidTest:

Collaboration diagram for TcpLinuxRenoCongAvoidTest:

Public Member Functions
	TcpLinuxRenoCongAvoidTest (uint32_t segmentSize, uint32_t packetSize, uint32_t packets, uint32_t initialCwnd, uint32_t initialSSThresh, uint32_t delayedAck, uint32_t expectedCwnd, TypeId &congControl, 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	CWndTrace (uint32_t oldValue, uint32_t newValue) override
	Tracks the congestion window changes.

void	DoTeardown () override
	Teardown the TCP test.

void	PhyDrop (SocketWho who) override
	Link drop.

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

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

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

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

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	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.

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

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

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

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 Member Functions
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.

Private Attributes
uint32_t	m_delayedAck
	Delayed Acknowledgement.

uint32_t	m_expectedCwnd
	Expected final cWnd value.

bool	m_inCongAvoidance
	True if in congestion avoidance.

uint32_t	m_increment
	Congestion window increment.

bool	m_initial
	True on first run.

uint32_t	m_initialCwnd
	Initial congestion window (segments)

uint32_t	m_initialSSThresh
	Initial slow start threshold (bytes)

bool	m_inSlowStartPhase
	True if in slow start.

uint32_t	m_lastCwnd
	Last cWnd value reported.

uint32_t	m_packets
	Number of packets to send to the socket.

uint32_t	m_packetSize
	Size of the packets used in socket writes.

uint32_t	m_segmentSize
	Segment size.

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

This unit test checks that the slow start and congestion avoidance behavior matches Linux behavior as follows: 1) in both slow start and congestion avoidance phases, presence or absence of delayed acks does not alter the window growth 2) in congestion avoidance phase, the arithmetic for counting the number of segments acked and deciding when to increment the congestion window (i.e.

following the Linux function tcp_cong_avoid_ai()) is followed. Different segment sizes (524 bytes and 1500 bytes) are tested.

This is the Congestion avoidance test.

Definition at line 198 of file tcp-linux-reno-test.cc.

Constructor & Destructor Documentation

◆ TcpLinuxRenoCongAvoidTest()

TcpLinuxRenoCongAvoidTest::TcpLinuxRenoCongAvoidTest	(	uint32_t	segmentSize,
		uint32_t	packetSize,
		uint32_t	packets,
		uint32_t	initialCwnd,
		uint32_t	initialSSThresh,
		uint32_t	delayedAck,
		uint32_t	expectedCwnd,
		TypeId &	congControl,
		const std::string &	desc )

Constructor.

Parameters

segmentSize	Segment size.
packetSize	Size of the packets.
packets	Number of packets.
initialCwnd	Initial congestion window (segments)
initialSSThresh	Initial slow start threshold (bytes)
delayedAck	Delayed Acknowledgement
expectedCwnd	Expected final m_cWnd value
congControl	Type of congestion control.
desc	The test description.

Definition at line 249 of file tcp-linux-reno-test.cc.

References ns3::TcpGeneralTest::m_congControlTypeId.

Member Function Documentation

◆ ConfigureEnvironment()

void TcpLinuxRenoCongAvoidTest::ConfigureEnvironment ( )

overrideprotectedvirtual

Change the configuration of the environment.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 276 of file tcp-linux-reno-test.cc.

References ns3::TcpGeneralTest::ConfigureEnvironment(), m_packets, m_packetSize, ns3::TcpGeneralTest::SetAppPktCount(), ns3::TcpGeneralTest::SetAppPktSize(), and ns3::TcpGeneralTest::SetMTU().

Here is the call graph for this function:

◆ ConfigureProperties()

void TcpLinuxRenoCongAvoidTest::ConfigureProperties ( )

overrideprotectedvirtual

Change the configuration of the socket properties.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 285 of file tcp-linux-reno-test.cc.

References ns3::TcpGeneralTest::ConfigureProperties(), m_delayedAck, m_initialCwnd, m_initialSSThresh, m_segmentSize, ns3::TcpGeneralTest::RECEIVER, ns3::TcpGeneralTest::SENDER, ns3::TcpGeneralTest::SetDelAckMaxCount(), ns3::TcpGeneralTest::SetInitialCwnd(), ns3::TcpGeneralTest::SetInitialSsThresh(), and ns3::TcpGeneralTest::SetSegmentSize().

Here is the call graph for this function:

◆ CWndTrace()

void TcpLinuxRenoCongAvoidTest::CWndTrace	(	uint32_t	oldValue,
		uint32_t	newValue )

overrideprotectedvirtual

Tracks the congestion window changes.

Parameters

oldValue	old value
newValue	new value

Reimplemented from ns3::TcpGeneralTest.

Definition at line 296 of file tcp-linux-reno-test.cc.

References m_inCongAvoidance, m_increment, m_initial, m_initialCwnd, m_initialSSThresh, m_inSlowStartPhase, m_lastCwnd, m_segmentSize, NS_LOG_FUNCTION, and NS_TEST_ASSERT_MSG_EQ.

◆ DoTeardown()

void TcpLinuxRenoCongAvoidTest::DoTeardown ( )

overrideprotectedvirtual

Teardown the TCP test.

Reimplemented from ns3::TcpGeneralTest.

Definition at line 352 of file tcp-linux-reno-test.cc.

References ns3::TcpGeneralTest::DoTeardown(), m_expectedCwnd, m_lastCwnd, and NS_TEST_ASSERT_MSG_EQ.

Here is the call graph for this function:

◆ PhyDrop()

void TcpLinuxRenoCongAvoidTest::PhyDrop ( SocketWho who )

overrideprotectedvirtual

Link drop.

Parameters

who	where the drop occurred (SENDER or RECEIVER)

Reimplemented from ns3::TcpGeneralTest.

Definition at line 334 of file tcp-linux-reno-test.cc.

References NS_FATAL_ERROR.

◆ QueueDrop()

void TcpLinuxRenoCongAvoidTest::QueueDrop ( SocketWho who )

overrideprotectedvirtual

Drop on the queue.

Parameters

who	where the drop occurred (SENDER or RECEIVER)

Reimplemented from ns3::TcpGeneralTest.

Definition at line 328 of file tcp-linux-reno-test.cc.

References NS_FATAL_ERROR.

◆ Rx()

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

overrideprivatevirtual

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 346 of file tcp-linux-reno-test.cc.

References NS_LOG_FUNCTION.

◆ Tx()

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

overrideprivatevirtual

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 340 of file tcp-linux-reno-test.cc.

References NS_LOG_FUNCTION.

Member Data Documentation

◆ m_delayedAck

uint32_t TcpLinuxRenoCongAvoidTest::m_delayedAck

private

Delayed Acknowledgement.

Definition at line 240 of file tcp-linux-reno-test.cc.

Referenced by ConfigureProperties().

◆ m_expectedCwnd

uint32_t TcpLinuxRenoCongAvoidTest::m_expectedCwnd

private

Expected final cWnd value.

Definition at line 242 of file tcp-linux-reno-test.cc.

Referenced by DoTeardown().

◆ m_inCongAvoidance

bool TcpLinuxRenoCongAvoidTest::m_inCongAvoidance

private

True if in congestion avoidance.

Definition at line 245 of file tcp-linux-reno-test.cc.

Referenced by CWndTrace().

◆ m_increment

uint32_t TcpLinuxRenoCongAvoidTest::m_increment

private

Congestion window increment.

Definition at line 243 of file tcp-linux-reno-test.cc.

Referenced by CWndTrace().

◆ m_initial

bool TcpLinuxRenoCongAvoidTest::m_initial

private

True on first run.

Definition at line 244 of file tcp-linux-reno-test.cc.

Referenced by CWndTrace().

◆ m_initialCwnd

uint32_t TcpLinuxRenoCongAvoidTest::m_initialCwnd

private

Initial congestion window (segments)

Definition at line 238 of file tcp-linux-reno-test.cc.

Referenced by ConfigureProperties(), and CWndTrace().

◆ m_initialSSThresh

uint32_t TcpLinuxRenoCongAvoidTest::m_initialSSThresh

private

Initial slow start threshold (bytes)

Definition at line 239 of file tcp-linux-reno-test.cc.

Referenced by ConfigureProperties(), and CWndTrace().

◆ m_inSlowStartPhase

bool TcpLinuxRenoCongAvoidTest::m_inSlowStartPhase

private

True if in slow start.

Definition at line 246 of file tcp-linux-reno-test.cc.

Referenced by CWndTrace().

◆ m_lastCwnd

uint32_t TcpLinuxRenoCongAvoidTest::m_lastCwnd

private

Last cWnd value reported.

Definition at line 241 of file tcp-linux-reno-test.cc.

Referenced by CWndTrace(), and DoTeardown().

◆ m_packets

uint32_t TcpLinuxRenoCongAvoidTest::m_packets

private

Number of packets to send to the socket.

Definition at line 237 of file tcp-linux-reno-test.cc.

Referenced by ConfigureEnvironment().

◆ m_packetSize

uint32_t TcpLinuxRenoCongAvoidTest::m_packetSize

private

Size of the packets used in socket writes.

Definition at line 236 of file tcp-linux-reno-test.cc.

Referenced by ConfigureEnvironment().

◆ m_segmentSize

uint32_t TcpLinuxRenoCongAvoidTest::m_segmentSize

private

Segment size.

Definition at line 235 of file tcp-linux-reno-test.cc.

Referenced by ConfigureProperties(), and CWndTrace().

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

src/internet/test/tcp-linux-reno-test.cc

Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ TcpLinuxRenoCongAvoidTest()

Member Function Documentation

◆ ConfigureEnvironment()

◆ ConfigureProperties()

◆ CWndTrace()

◆ DoTeardown()

◆ PhyDrop()

◆ QueueDrop()

◆ Rx()

◆ Tx()

Member Data Documentation

◆ m_delayedAck

◆ m_expectedCwnd

◆ m_inCongAvoidance

◆ m_increment

◆ m_initial

◆ m_initialCwnd

◆ m_initialSSThresh

◆ m_inSlowStartPhase

◆ m_lastCwnd

◆ m_packets

◆ m_packetSize

◆ m_segmentSize