Data structure that records the congestion state of a connection. More...

#include "tcp-socket-base.h"

Inheritance diagram for ns3::TcpSocketState:

Collaboration diagram for ns3::TcpSocketState:

Public Types
enum	TcpCongState_t { CA_OPEN, CA_DISORDER, CA_CWR, CA_RECOVERY, CA_LOSS, CA_LAST_STATE }
	Definition of the Congestion state machine. More...

typedef void(*	TcpCongStatesTracedValueCallback) (const TcpCongState_t oldValue, const TcpCongState_t newValue)
	TracedValue Callback signature for TcpCongState_t. More...

Public Member Functions
	TcpSocketState ()

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

uint32_t	GetCwndInSegments () const
	Get cwnd in segments rather than bytes. More...

uint32_t	GetSsThreshInSegments () const
	Get slow start thresh in segments rather than bytes. 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
	Implement the GetInstanceTypeId method defined in ObjectBase. 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...

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 ()
	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. 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::Object
static TypeId	GetTypeId (void)
	Register this type. More...

Static Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
static void	Cleanup (void)
	Noop. More...

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

Public Attributes
TracedValue< TcpCongState_t >	m_congState
	State in the Congestion state machine. More...

TracedValue< uint32_t >	m_cWnd
	Congestion window. More...

TracedValue< SequenceNumber32 >	m_highTxMark
	Highest seqno ever sent, regardless of ReTx. More...

uint32_t	m_initialCWnd
	Initial cWnd value. More...

uint32_t	m_initialSsThresh
	Initial Slow Start Threshold value. More...

SequenceNumber32	m_lastAckedSeq
	Last sequence ACKed. More...

TracedValue< SequenceNumber32 >	m_nextTxSequence
	Next seqnum to be sent (SND.NXT), ReTx pushes it back. More...

uint32_t	m_segmentSize
	Segment size. More...

TracedValue< uint32_t >	m_ssThresh
	Slow start threshold. More...

Static Public Attributes
static const char *const	TcpCongStateName [TcpSocketState::CA_LAST_STATE]
	Literal names of TCP states for use in log messages. More...

Additional Inherited Members
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

Data structure that records the congestion state of a connection.

In this data structure, basic informations that should be passed between socket and the congestion control algorithm are saved. Through the code, it will be referred as Transmission Control Block (TCB), but there are some differencies. In the RFCs, the TCB contains all the variables that defines a connection, while we preferred to maintain in this class only the values that should be exchanged between socket and other parts, like congestion control algorithms.

Definition at line 92 of file tcp-socket-base.h.

Member Enumeration Documentation

enum ns3::TcpSocketState::TcpCongState_t

Definition of the Congestion state machine.

The design of this state machine is taken from Linux v4.0, but it has been maintained in the Linux mainline from ages. It basically avoids to maintain a lot of boolean variables, and it allows to check the transitions from different algorithm in a cleaner way.

These states represent the situation from a congestion control point of view: in fact, apart the CA_OPEN state, the other states represent a situation in which there is a congestion, and different actions should be taken, depending on the case.

Enumerator
CA_OPEN	Normal state, no dubious events.
CA_DISORDER	In all the respects it is "Open", but requires a bit more attention. It is entered when we see some SACKs or dupacks. It is split of "Open"
CA_CWR	cWnd was reduced due to some Congestion Notification event. It can be ECN, ICMP source quench, local device congestion. Not used in NS-3 right now.
CA_RECOVERY	CWND was reduced, we are fast-retransmitting.
CA_LOSS	CWND was reduced due to RTO timeout or SACK reneging.
CA_LAST_STATE	Used only in debug messages.

Definition at line 124 of file tcp-socket-base.h.

Constructor & Destructor Documentation

ns3::TcpSocketState::TcpSocketState ( void )

Definition at line 230 of file tcp-socket-base.cc.

ns3::TcpSocketState::TcpSocketState ( const TcpSocketState & other )

Copy constructor.

Parameters

other object to copy.

Definition at line 245 of file tcp-socket-base.cc.

Member Function Documentation

uint32_t ns3::TcpSocketState::GetCwndInSegments ( ) const

inline

Get cwnd in segments rather than bytes.

Returns: Congestion window in segments

Definition at line 172 of file tcp-socket-base.h.

References m_segmentSize.

uint32_t ns3::TcpSocketState::GetSsThreshInSegments ( ) const

inline

Get slow start thresh in segments rather than bytes.

Returns: Slow start threshold in segments

Definition at line 182 of file tcp-socket-base.h.

References m_segmentSize.

TypeId ns3::TcpSocketState::GetTypeId ( void )

static

Get the type ID.

Returns: the object TypeId

Definition at line 200 of file tcp-socket-base.cc.

References m_congState, m_cWnd, m_highTxMark, m_nextTxSequence, m_ssThresh, ns3::MakeTraceSourceAccessor(), and ns3::TypeId::SetParent().

Here is the call graph for this function:

Member Data Documentation

TracedValue<TcpCongState_t> ns3::TcpSocketState::m_congState

State in the Congestion state machine.

Definition at line 163 of file tcp-socket-base.h.

Referenced by ns3::GetCongStateFrom(), and GetTypeId().

TracedValue<uint32_t> ns3::TcpSocketState::m_cWnd

Congestion window.

Definition at line 154 of file tcp-socket-base.h.

Referenced by ns3::TcpVenoTest::DoRun(), GetTypeId(), ns3::NewReno_CongestionAvoidance(), ns3::NewReno_IncreaseWindow(), and ns3::NewReno_SlowStart().

TracedValue<SequenceNumber32> ns3::TcpSocketState::m_highTxMark

Highest seqno ever sent, regardless of ReTx.

Definition at line 164 of file tcp-socket-base.h.

Referenced by GetTypeId().

uint32_t ns3::TcpSocketState::m_initialCWnd

Initial cWnd value.

Definition at line 156 of file tcp-socket-base.h.

uint32_t ns3::TcpSocketState::m_initialSsThresh

Initial Slow Start Threshold value.

Definition at line 157 of file tcp-socket-base.h.

SequenceNumber32 ns3::TcpSocketState::m_lastAckedSeq

Last sequence ACKed.

Definition at line 161 of file tcp-socket-base.h.

TracedValue<SequenceNumber32> ns3::TcpSocketState::m_nextTxSequence

Next seqnum to be sent (SND.NXT), ReTx pushes it back.

Definition at line 165 of file tcp-socket-base.h.

Referenced by GetTypeId().

uint32_t ns3::TcpSocketState::m_segmentSize

Segment size.

Definition at line 160 of file tcp-socket-base.h.

Referenced by ns3::TcpVenoTest::DoRun(), GetCwndInSegments(), GetSsThreshInSegments(), ns3::NewReno_CongestionAvoidance(), and ns3::NewReno_SlowStart().

TracedValue<uint32_t> ns3::TcpSocketState::m_ssThresh

Slow start threshold.

Definition at line 155 of file tcp-socket-base.h.

Referenced by ns3::TcpVenoTest::DoRun(), GetTypeId(), and ns3::NewReno_IncreaseWindow().

const char *const ns3::TcpSocketState::TcpCongStateName

static

Initial value:

=
{
  "CA_OPEN", "CA_DISORDER", "CA_CWR", "CA_RECOVERY", "CA_LOSS"
}

Literal names of TCP states for use in log messages.

Definition at line 151 of file tcp-socket-base.h.

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

src/internet/model/tcp-socket-base.h
src/internet/model/tcp-socket-base.cc

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Static Public Attributes

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation