Congestion control abstract class. More...

#include "tcp-congestion-ops.h"

Inheritance diagram for ns3::TcpCongestionOps:

Collaboration diagram for ns3::TcpCongestionOps:

Public Member Functions
	TcpCongestionOps ()

	TcpCongestionOps (const TcpCongestionOps &other)

virtual	~TcpCongestionOps ()

virtual Ptr< TcpCongestionOps >	Fork ()=0
	Copy the congestion control algorithm across socket. More...

virtual std::string	GetName () const =0
	Get the name of the congestion control algorithm. More...

virtual uint32_t	GetSsThresh (Ptr< const TcpSocketState > tcb, uint32_t bytesInFlight)=0
	Get the slow start threshold after a loss event. More...

virtual void	IncreaseWindow (Ptr< TcpSocketState > tcb, uint32_t segmentsAcked)=0
	Congestion avoidance algorithm implementation. More...

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

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...

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

Congestion control abstract class.

Introspection did not find any typical Config paths.

The design is inspired on what Linux v4.0 does (but it has been in place since years). The congestion control is splitted from the main socket code, and it is a pluggable component. An interface has been defined; variables are maintained in the TcpSocketState class, while subclasses of TcpCongestionOps operate over an instance of that class.

Only three methods has been utilized right now; however, Linux has many others, which can be added later in ns-3.

See also: IncreaseWindow; PktsAcked

No Attributes are defined for this type.
No TraceSources are defined for this type.
Size of this type is 32 bytes (on a 64-bit architecture).

Definition at line 45 of file tcp-congestion-ops.h.

Constructor & Destructor Documentation

ns3::TcpCongestionOps::TcpCongestionOps ( )

Definition at line 39 of file tcp-congestion-ops.cc.

ns3::TcpCongestionOps::TcpCongestionOps ( const TcpCongestionOps & other )

Definition at line 43 of file tcp-congestion-ops.cc.

ns3::TcpCongestionOps::~TcpCongestionOps ( )

virtual

Definition at line 47 of file tcp-congestion-ops.cc.

Member Function Documentation

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

pure virtual

Copy the congestion control algorithm across socket.

Returns: a pointer of the copied object

Implemented in ns3::TcpNewReno, ns3::TcpWestwood, ns3::TcpHighSpeed, and ns3::TcpHybla.

virtual std::string ns3::TcpCongestionOps::GetName ( ) const

pure virtual

Get the name of the congestion control algorithm.

Returns: A string identifying the name

Implemented in ns3::TcpNewReno, ns3::TcpHighSpeed, and ns3::TcpHybla.

virtual uint32_t ns3::TcpCongestionOps::GetSsThresh	(	Ptr< const TcpSocketState >	tcb,
		uint32_t	bytesInFlight
	)

pure virtual

Get the slow start threshold after a loss event.

Is guaranteed that the congestion control state (TcpAckState_t) is changed BEFORE the invocation of this method. The implementator should return the slow start threshold (and not change it directly) because, in the future, the TCP implementation may require to instantly recover from a loss event (e.g. when there is a network with an high reordering factor).

Parameters

tcb	internal congestion state
bytesInFlight	total bytes in flight

Returns: Slow start threshold

Implemented in ns3::TcpNewReno, ns3::TcpWestwood, and ns3::TcpHighSpeed.

TypeId ns3::TcpCongestionOps::GetTypeId ( void )

static

Get the type ID.

Returns: the object TypeId

Definition at line 30 of file tcp-congestion-ops.cc.

References ns3::TypeId::SetParent().

Here is the call graph for this function:

virtual void ns3::TcpCongestionOps::IncreaseWindow	(	Ptr< TcpSocketState >	tcb,
		uint32_t	segmentsAcked
	)

pure virtual

Congestion avoidance algorithm implementation.

Mimic the function cong_avoid in Linux. New segments have been ACKed, and the congestion control duty is to set

The function is allowed to change directly cWnd and/or ssThresh.

Parameters

tcb	internal congestion state
segmentsAcked	count of segments acked

Implemented in ns3::TcpNewReno.

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

inlinevirtual

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 can not implement it) and the default implementation does nothing.

Parameters

tcb	internal congestion state
segmentsAcked	count of segments acked
rtt	last rtt

Reimplemented in ns3::TcpWestwood, and ns3::TcpHybla.

Definition at line 108 of file tcp-congestion-ops.h.

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

src/internet/model/tcp-congestion-ops.h
src/internet/model/tcp-congestion-ops.cc

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation