An implementation of DCTCP. More...

#include "tcp-dctcp.h"

Inheritance diagram for ns3::TcpDctcp:

Collaboration diagram for ns3::TcpDctcp:

Public Member Functions
	TcpDctcp ()
	Create an unbound tcp socket. More...

	TcpDctcp (const TcpDctcp &sock)
	Copy constructor. More...

virtual	~TcpDctcp (void)
	Destructor. More...

virtual void	CwndEvent (Ptr< TcpSocketState > tcb, const TcpSocketState::TcpCAEvent_t event)
	Trigger events/calculations on occurrence of congestion window event. More...

virtual Ptr< TcpCongestionOps >	Fork ()
	Copy the congestion control algorithm across sockets. More...

virtual std::string	GetName () const
	Get the name of the congestion control algorithm. More...

virtual void	Init (Ptr< TcpSocketState > tcb)
	Set configuration required by congestion control algorithm, This method will force DctcpEcn mode and will force usage of either ECT(0) or ECT(1) (depending on the 'UseEct0' attribute), despite any other configuration in the base classes. More...

virtual void	PktsAcked (Ptr< TcpSocketState > tcb, uint32_t segmentsAcked, const Time &rtt)
	Timing information on received ACK. More...

virtual void	ReduceCwnd (Ptr< TcpSocketState > tcb)
	Reduces congestion window on receipt of ECN Echo Flag. More...

Public Member Functions inherited from ns3::TcpNewReno
	TcpNewReno ()

	TcpNewReno (const TcpNewReno &sock)
	Copy constructor. More...

	~TcpNewReno ()

virtual uint32_t	GetSsThresh (Ptr< const TcpSocketState > tcb, uint32_t bytesInFlight)
	Get the slow start threshold after a loss event. More...

virtual void	IncreaseWindow (Ptr< TcpSocketState > tcb, uint32_t segmentsAcked)
	Try to increase the cWnd following the NewReno specification. More...

Public Member Functions inherited from ns3::TcpCongestionOps
	TcpCongestionOps ()

	TcpCongestionOps (const TcpCongestionOps &other)
	Copy constructor. More...

virtual	~TcpCongestionOps ()

virtual void	CongControl (Ptr< TcpSocketState > tcb, const TcpRateOps::TcpRateConnection &rc, const TcpRateOps::TcpRateSample &rs)
	Called when packets are delivered to update cwnd and pacing rate. More...

virtual void	CongestionStateSet (Ptr< TcpSocketState > tcb, const TcpSocketState::TcpCongState_t newState)
	Trigger events/calculations specific to a congestion state. More...

virtual bool	HasCongControl () const
	Returns true when Congestion Control Algorithm implements CongControl. More...

Public Member Functions inherited from ns3::Object
	Object ()
	Constructor. More...

virtual	~Object ()
	Destructor. More...

void	AggregateObject (Ptr< Object > other)
	Aggregate two Objects together. More...

void	Dispose (void)
	Dispose of this Object. More...

AggregateIterator	GetAggregateIterator (void) const
	Get an iterator to the Objects aggregated to this one. More...

virtual TypeId	GetInstanceTypeId (void) const
	Get the most derived TypeId for this Object. More...

template<typename T >
Ptr< T >	GetObject (void) const
	Get a pointer to the requested aggregated Object. More...

template<typename T >
Ptr< T >	GetObject (TypeId tid) const
	Get a pointer to the requested aggregated Object by TypeId. More...

template<>
Ptr< Object >	GetObject () const

template<>
Ptr< Object >	GetObject (TypeId tid) const

void	Initialize (void)
	Invoke DoInitialize on all Objects aggregated to this one. More...

bool	IsInitialized (void) const
	Check if the object has been initialized. More...

Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount ()
	Default constructor. More...

	SimpleRefCount (const SimpleRefCount &o)
	Copy constructor. More...

uint32_t	GetReferenceCount (void) const
	Get the reference count of the object. More...

SimpleRefCount &	operator= (const SimpleRefCount &o)
	Assignment operator. More...

void	Ref (void) const
	Increment the reference count. More...

void	Unref (void) const
	Decrement the reference count. More...

Public Member Functions inherited from ns3::ObjectBase
virtual	~ObjectBase ()
	Virtual destructor. More...

void	GetAttribute (std::string name, AttributeValue &value) const
	Get the value of an attribute, raising fatal errors if unsuccessful. More...

bool	GetAttributeFailSafe (std::string name, AttributeValue &value) const
	Get the value of an attribute without raising erros. More...

void	SetAttribute (std::string name, const AttributeValue &value)
	Set a single attribute, raising fatal errors if unsuccessful. More...

bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)
	Set a single attribute without raising errors. More...

bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)
	Connect a TraceSource to a Callback with a context. More...

bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)
	Connect a TraceSource to a Callback without a context. More...

bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected with a context. More...

bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected without a context. More...

Static Public Member Functions
static TypeId	GetTypeId (void)
	Get the type ID. More...

Static Public Member Functions inherited from ns3::TcpNewReno
static TypeId	GetTypeId (void)
	Get the type ID. More...

Static Public Member Functions inherited from ns3::TcpCongestionOps
static TypeId	GetTypeId (void)
	Get the type ID. More...

Static Public Member Functions inherited from ns3::Object
static TypeId	GetTypeId (void)
	Register this type. More...

Static Public Member Functions inherited from ns3::ObjectBase
static TypeId	GetTypeId (void)
	Get the type ID. More...

Private Member Functions
void	CeState0to1 (Ptr< TcpSocketState > tcb)
	Changes state of m_ceState to true. More...

void	CeState1to0 (Ptr< TcpSocketState > tcb)
	Changes state of m_ceState to false. More...

void	Reset (Ptr< TcpSocketState > tcb)
	Resets the value of m_ackedBytesEcn, m_ackedBytesTotal and m_nextSeq. More...

void	SetDctcpAlpha (double alpha)
	Sets the value of m_alpha. More...

void	UpdateAckReserved (Ptr< TcpSocketState > tcb, const TcpSocketState::TcpCAEvent_t event)
	Updates the value of m_delayedAckReserved. More...

Private Attributes
uint32_t	m_ackedBytesEcn
	Number of acked bytes which are marked. More...

uint32_t	m_ackedBytesTotal
	Total number of acked bytes. More...

double	m_alpha
	Parameter used to estimate the amount of network congestion. More...

bool	m_ceState
	DCTCP Congestion Experienced state. More...

bool	m_delayedAckReserved
	Delayed Ack state. More...

double	m_g
	Estimation gain. More...

SequenceNumber32	m_nextSeq
	TCP sequence number threshold for beginning a new observation window. More...

bool	m_nextSeqFlag
	Variable used in setting the value of m_nextSeq for first time. More...

SequenceNumber32	m_priorRcvNxt
	Sequence number of the first missing byte in data. More...

bool	m_priorRcvNxtFlag
	Variable used in setting the value of m_priorRcvNxt for first time. More...

bool	m_useEct0
	Use ECT(0) for ECN codepoint. More...

Additional Inherited Members
Protected Member Functions inherited from ns3::TcpNewReno
virtual void	CongestionAvoidance (Ptr< TcpSocketState > tcb, uint32_t segmentsAcked)
	NewReno congestion avoidance. More...

virtual uint32_t	SlowStart (Ptr< TcpSocketState > tcb, uint32_t segmentsAcked)
	Tcp NewReno slow start algorithm More...

Protected Member Functions inherited from ns3::Object
	Object (const Object &o)
	Copy an Object. More...

virtual void	DoDispose (void)
	Destructor implementation. More...

virtual void	DoInitialize (void)
	Initialize() implementation. More...

virtual void	NotifyNewAggregate (void)
	Notify all Objects aggregated to this one of a new Object being aggregated. More...

Protected Member Functions inherited from ns3::ObjectBase
void	ConstructSelf (const AttributeConstructionList &attributes)
	Complete construction of ObjectBase; invoked by derived classes. More...

virtual void	NotifyConstructionCompleted (void)
	Notifier called once the ObjectBase is fully constructed. More...

Related Functions inherited from ns3::ObjectBase
static TypeId	GetObjectIid (void)
	Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly. More...

Detailed Description

An implementation of DCTCP.

Introspection did not find any typical Config paths.

This model implements all of the endpoint capabilities mentioned in the DCTCP SIGCOMM paper.

Attributes

DctcpShiftG: Parameter G for updating dctcp_alpha
- Set with class: ns3::DoubleValue
- Underlying type: double 0:1
- Initial value: 0.0625
- Flags: construct write read
DctcpAlphaOnInit: Initial alpha value
- Set with class: ns3::DoubleValue
- Underlying type: double 0:1
- Initial value: 1
- Flags: construct write
UseEct0: Use ECT(0) for ECN codepoint, if false use ECT(1)
- Set with class: BooleanValue
- Underlying type: bool
- Initial value: true
- Flags: construct write read

No TraceSources are defined for this type.
Size of this type is 80 bytes (on a 64-bit architecture).

Definition at line 36 of file tcp-dctcp.h.

Constructor & Destructor Documentation

◆ TcpDctcp() [1/2]

ns3::TcpDctcp::TcpDctcp ( )

Create an unbound tcp socket.

Definition at line 63 of file tcp-dctcp.cc.

References m_ackedBytesEcn, m_ackedBytesTotal, m_ceState, m_delayedAckReserved, m_nextSeq, m_nextSeqFlag, m_priorRcvNxt, m_priorRcvNxtFlag, and NS_LOG_FUNCTION.

◆ TcpDctcp() [2/2]

ns3::TcpDctcp::TcpDctcp ( const TcpDctcp & sock )

Copy constructor.

Parameters

sock	the object to copy

Definition at line 77 of file tcp-dctcp.cc.

References NS_LOG_FUNCTION.

◆ ~TcpDctcp()

ns3::TcpDctcp::~TcpDctcp ( void )

virtual

Destructor.

Definition at line 94 of file tcp-dctcp.cc.

References NS_LOG_FUNCTION.

Member Function Documentation

◆ CeState0to1()

void ns3::TcpDctcp::CeState0to1 ( Ptr< TcpSocketState > tcb )

private

Changes state of m_ceState to true.

Parameters

tcb	internal congestion state

Definition at line 167 of file tcp-dctcp.cc.

References ns3::TcpHeader::ACK, ns3::TcpSocketState::ECN_CE_RCVD, m_ceState, m_delayedAckReserved, ns3::TcpSocketState::m_ecnState, m_priorRcvNxt, m_priorRcvNxtFlag, ns3::TcpSocketState::m_rxBuffer, ns3::TcpSocketState::m_sendEmptyPacketCallback, and NS_LOG_FUNCTION.

Referenced by CwndEvent().

Here is the caller graph for this function:

◆ CeState1to0()

void ns3::TcpDctcp::CeState1to0 ( Ptr< TcpSocketState > tcb )

private

Changes state of m_ceState to false.

Parameters

tcb	internal congestion state

Definition at line 194 of file tcp-dctcp.cc.

References ns3::TcpHeader::ACK, ns3::TcpHeader::ECE, ns3::TcpSocketState::ECN_CE_RCVD, ns3::TcpSocketState::ECN_IDLE, ns3::TcpSocketState::ECN_SENDING_ECE, m_ceState, m_delayedAckReserved, ns3::TcpSocketState::m_ecnState, m_priorRcvNxt, m_priorRcvNxtFlag, ns3::TcpSocketState::m_rxBuffer, ns3::TcpSocketState::m_sendEmptyPacketCallback, and NS_LOG_FUNCTION.

Referenced by CwndEvent().

Here is the caller graph for this function:

◆ CwndEvent()

void ns3::TcpDctcp::CwndEvent	(	Ptr< TcpSocketState >	tcb,
		const TcpSocketState::TcpCAEvent_t	event
	)

virtual

Trigger events/calculations on occurrence of congestion window event.

This function mimics the function cwnd_event in Linux. The function is called in case of congestion window events.

Parameters

tcb	internal congestion state
event	the event which triggered this function

Reimplemented from ns3::TcpCongestionOps.

Definition at line 250 of file tcp-dctcp.cc.

References ns3::TcpSocketState::CA_EVENT_DELAYED_ACK, ns3::TcpSocketState::CA_EVENT_ECN_IS_CE, ns3::TcpSocketState::CA_EVENT_ECN_NO_CE, ns3::TcpSocketState::CA_EVENT_NON_DELAYED_ACK, CeState0to1(), CeState1to0(), NS_LOG_FUNCTION, and UpdateAckReserved().

Here is the call graph for this function:

◆ Fork()

Ptr< TcpCongestionOps > ns3::TcpDctcp::Fork ( )

virtual

Copy the congestion control algorithm across sockets.

Returns: a pointer of the copied object

Reimplemented from ns3::TcpNewReno.

Definition at line 99 of file tcp-dctcp.cc.

References NS_LOG_FUNCTION.

◆ GetName()

std::string ns3::TcpDctcp::GetName ( ) const

virtual

Get the name of the congestion control algorithm.

Returns: A string identifying the name

Reimplemented from ns3::TcpNewReno.

Definition at line 58 of file tcp-dctcp.cc.

◆ GetTypeId()

TypeId ns3::TcpDctcp::GetTypeId ( void )

static

Get the type ID.

Returns: the object TypeId

Definition at line 33 of file tcp-dctcp.cc.

References m_g, m_useEct0, ns3::MakeBooleanAccessor(), ns3::MakeBooleanChecker(), ns3::MakeDoubleAccessor(), SetDctcpAlpha(), and ns3::TypeId::SetParent().

Here is the call graph for this function:

◆ Init()

void ns3::TcpDctcp::Init ( Ptr< TcpSocketState > tcb )

virtual

Set configuration required by congestion control algorithm, This method will force DctcpEcn mode and will force usage of either ECT(0) or ECT(1) (depending on the 'UseEct0' attribute), despite any other configuration in the base classes.

Parameters

tcb	internal congestion state

Reimplemented from ns3::TcpCongestionOps.

Definition at line 106 of file tcp-dctcp.cc.

References ns3::TcpSocketState::DctcpEcn, ns3::TcpSocketState::Ect0, ns3::TcpSocketState::Ect1, ns3::TcpSocketState::m_ecnMode, ns3::TcpSocketState::m_ectCodePoint, ns3::TcpSocketState::m_useEcn, m_useEct0, NS_LOG_FUNCTION, NS_LOG_INFO, and ns3::TcpSocketState::On.

◆ PktsAcked()

void ns3::TcpDctcp::PktsAcked	(	Ptr< TcpSocketState >	tcb,
		uint32_t	segmentsAcked,
		const Time &	rtt
	)

virtual

Timing information on received ACK.

The function is called every time an ACK is received (only one time also for cumulative ACKs) and contains timing information. It is optional (congestion controls need not implement it) and the default implementation does nothing.

Parameters