Defines the TCP option of kind 3 (window scale option) as in RFC 1323 More...

#include "tcp-option-winscale.h"

Inheritance diagram for ns3::TcpOptionWinScale:

Collaboration diagram for ns3::TcpOptionWinScale:

Public Member Functions
	TcpOptionWinScale ()
	~TcpOptionWinScale () override
uint32_t	Deserialize (Buffer::Iterator start) override
	Deserialize the Option from a buffer iterator.
uint8_t	GetKind () const override
	Get the ‘kind’ (as in RFC 793) of this option.
uint8_t	GetScale () const
	Get the scale value (uint8_t)
uint32_t	GetSerializedSize () const override
	Returns number of bytes required for Option serialization.
void	Print (std::ostream &os) const override
	Print the Option contents.
void	Serialize (Buffer::Iterator start) const override
	Serialize the Option to a buffer iterator.
void	SetScale (uint8_t scale)
	Set the scale option.
Public Member Functions inherited from ns3::TcpOption
	TcpOption ()
	~TcpOption () override
Public Member Functions inherited from ns3::Object
	Object ()
	Constructor.
	~Object () override
	Destructor.
void	AggregateObject (Ptr< Object > other)
	Aggregate two Objects together.
void	Dispose ()
	Dispose of this Object.
AggregateIterator	GetAggregateIterator () const
	Get an iterator to the Objects aggregated to this one.
TypeId	GetInstanceTypeId () const final
	Get the most derived TypeId for this Object.
template<typename T>
Ptr< T >	GetObject () const
	Get a pointer to the requested aggregated Object.
template<>
Ptr< Object >	GetObject () const
	Specialization of () for objects of type ns3::Object.
template<typename T>
Ptr< T >	GetObject (TypeId tid) const
	Get a pointer to the requested aggregated Object by TypeId.
template<>
Ptr< Object >	GetObject (TypeId tid) const
	Specialization of (TypeId tid) for objects of type ns3::Object.
void	Initialize ()
	Invoke DoInitialize on all Objects aggregated to this one.
bool	IsInitialized () const
	Check if the object has been initialized.
void	UnidirectionalAggregateObject (Ptr< Object > other)
	Aggregate an Object to another Object.
Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount ()
	Default constructor.
uint32_t	GetReferenceCount () const
	Get the reference count of the object.
SimpleRefCount &	operator= (const SimpleRefCount &o)
	Assignment operator.
void	Ref () const
	Increment the reference count.
void	Unref () const
	Decrement the reference count.
Public Member Functions inherited from ns3::ObjectBase
virtual	~ObjectBase ()
	Virtual destructor.
void	GetAttribute (std::string name, AttributeValue &value, bool permissive=false) const
	Get the value of an attribute, raising fatal errors if unsuccessful.
bool	GetAttributeFailSafe (std::string name, AttributeValue &value) const
	Get the value of an attribute without raising errors.
void	SetAttribute (std::string name, const AttributeValue &value)
	Set a single attribute, raising fatal errors if unsuccessful.
bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)
	Set a single attribute without raising errors.
bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)
	Connect a TraceSource to a Callback with a context.
bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)
	Connect a TraceSource to a Callback without a context.
bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected with a context.
bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected without a context.

Static Public Member Functions
static TypeId	GetTypeId ()
	Get the type ID.
Static Public Member Functions inherited from ns3::TcpOption
static Ptr< TcpOption >	CreateOption (uint8_t kind)
	Creates an option.
static TypeId	GetTypeId ()
	Get the type ID.
static bool	IsKindKnown (uint8_t kind)
	Check if the option is implemented.
Static Public Member Functions inherited from ns3::Object
static TypeId	GetTypeId ()
	Register this type.
Static Public Member Functions inherited from ns3::ObjectBase
static TypeId	GetTypeId ()
	Get the type ID.

Protected Attributes
uint8_t	m_scale
	Window scaling in number of bit shift.

Additional Inherited Members
Public Types inherited from ns3::TcpOption
enum	Kind { END = 0 , NOP = 1 , MSS = 2 , WINSCALE = 3 , SACKPERMITTED = 4 , SACK = 5 , TS = 8 , UNKNOWN = 255 }
	The option Kind, as defined in the respective RFCs. More...
Protected Member Functions inherited from ns3::Object
	Object (const Object &o)
	Copy an Object.
virtual void	DoDispose ()
	Destructor implementation.
virtual void	DoInitialize ()
	Initialize() implementation.
virtual void	NotifyNewAggregate ()
	Notify all Objects aggregated to this one of a new Object being aggregated.
Protected Member Functions inherited from ns3::ObjectBase
void	ConstructSelf (const AttributeConstructionList &attributes)
	Complete construction of ObjectBase; invoked by derived classes.
virtual void	NotifyConstructionCompleted ()
	Notifier called once the ObjectBase is fully constructed.
Related Symbols inherited from ns3::ObjectBase
static TypeId	GetObjectIid ()
	Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly.

Detailed Description

Defines the TCP option of kind 3 (window scale option) as in RFC 1323

For more efficient use of high bandwidth networks, a larger TCP window size may be used. The TCP window size field controls the flow of data and its value is limited to between 2 and 65,535 bytes.

Since the size field cannot be expanded, a scaling factor is used. The TCP window scale option, as defined in RFC 1323, is an option used to increase the maximum window size from 65,535 bytes to 1 gigabyte. Scaling up to larger window sizes is a part of what is necessary for TCP Tuning.

The window scale option is used only during the TCP 3-way handshake. The window scale value represents the number of bits to left-shift the 16-bit window size field. The window scale value can be set from 0 (no shift) to 14 for each direction independently. Both sides must send the option in their SYN segments to enable window scaling in either direction.

Definition at line 39 of file tcp-option-winscale.h.