Abstract base class for Ndn forwarding strategies. More...

#include <ndn-forwarding-strategy.h>

Inheritance diagram for ns3::ndn::ForwardingStrategy:

Collaboration diagram for ns3::ndn::ForwardingStrategy:

Public Member Functions
	ForwardingStrategy ()
	Default constructor.

virtual void	OnInterest (Ptr< Face > face, Ptr< Interest > interest)
	Actual processing of incoming Ndn interests. More...

virtual void	OnData (Ptr< Face > face, Ptr< Data > data)
	Actual processing of incoming Ndn content objects. More...

virtual void	WillEraseTimedOutPendingInterest (Ptr< pit::Entry > pitEntry)
	Event fired just before PIT entry is removed by timeout. More...

virtual void	AddFace (Ptr< Face > face)
	Event fired every time face is added to NDN stack. More...

virtual void	RemoveFace (Ptr< Face > face)
	Event fired every time face is removed from NDN stack. More...

virtual void	DidAddFibEntry (Ptr< fib::Entry > fibEntry)
	Event fired every time a FIB entry is added to FIB. More...

virtual void	WillRemoveFibEntry (Ptr< fib::Entry > fibEntry)
	Fired just before FIB entry will be removed from FIB. More...

Static Public Member Functions
static TypeId	GetTypeId ()

static std::string	GetLogName ()
	Helper function to retrieve logging name for the forwarding strategy.

Protected Member Functions
virtual void	DidCreatePitEntry (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	An event that is fired every time a new PIT entry is created. More...

virtual void	FailedToCreatePitEntry (Ptr< Face > inFace, Ptr< const Interest > interest)
	An event that is fired every time a new PIT entry cannot be created (e.g., PIT container imposes a limit) More...

virtual void	DidReceiveDuplicateInterest (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	An event that is fired every time a duplicated Interest is received. More...

virtual void	DidSuppressSimilarInterest (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	An event that is fired every time when a similar Interest is received and suppressed (collapsed) More...

virtual void	DidForwardSimilarInterest (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	An event that is fired every time when a similar Interest is received and further forwarded (not suppressed/collapsed) More...

virtual void	DidExhaustForwardingOptions (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	An even that is fired when Interest cannot be forwarded. More...

virtual bool	DetectRetransmittedInterest (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	Method that implements logic to distinguish between new and retransmitted interest. More...

virtual void	WillSatisfyPendingInterest (Ptr< Face > inFace, Ptr< pit::Entry > pitEntry)
	Even fired just before Interest will be satisfied. More...

virtual void	SatisfyPendingInterest (Ptr< Face > inFace, Ptr< const Data > data, Ptr< pit::Entry > pitEntry)
	Actual procedure to satisfy Interest. More...

virtual void	DidSendOutData (Ptr< Face > inFace, Ptr< Face > outFace, Ptr< const Data > data, Ptr< pit::Entry > pitEntry)
	Event which is fired just after data was send out on the face. More...

virtual void	DidReceiveSolicitedData (Ptr< Face > inFace, Ptr< const Data > data, bool didCreateCacheEntry)
	Event which is fired every time a requested (solicited) DATA packet (there is an active PIT entry) is received. More...

virtual void	DidReceiveUnsolicitedData (Ptr< Face > inFace, Ptr< const Data > data, bool didCreateCacheEntry)
	Event which is fired every time an unsolicited DATA packet (no active PIT entry) is received. More...

virtual bool	ShouldSuppressIncomingInterest (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	Method implementing logic to suppress (collapse) similar Interests. More...

virtual bool	CanSendOutInterest (Ptr< Face > inFace, Ptr< Face > outFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	Method to check whether Interest can be send out on the particular face or not. More...

virtual bool	TrySendOutInterest (Ptr< Face > inFace, Ptr< Face > outFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	Method implementing actual interest forwarding, taking into account CanSendOutInterest decision. More...

virtual void	DidSendOutInterest (Ptr< Face > inFace, Ptr< Face > outFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	Event fired just after forwarding the Interest. More...

virtual void	PropagateInterest (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)
	Wrapper method, which performs general tasks and calls DoPropagateInterest method. More...

virtual bool	DoPropagateInterest (Ptr< Face > inFace, Ptr< const Interest > interest, Ptr< pit::Entry > pitEntry)=0
	Virtual method to perform Interest propagation according to the forwarding strategy logic. More...

virtual void	NotifyNewAggregate ()
	Even when object is aggregated to another Object.

virtual void	DoDispose ()
	Do cleanup.

Protected Attributes
Ptr< Pit >	m_pit
	Reference to PIT to which this forwarding strategy is associated.

Ptr< Fib >	m_fib
	FIB.

Ptr< ContentStore >	m_contentStore
	Content store (for caching purposes only)

bool	m_cacheUnsolicitedDataFromApps

bool	m_cacheUnsolicitedData

bool	m_detectRetransmissions

TracedCallback< Ptr< const Interest >, Ptr< const Face > >	m_outInterests
	Transmitted interests trace.

TracedCallback< Ptr< const Interest >, Ptr< const Face > >	m_inInterests
	trace of incoming Interests

TracedCallback< Ptr< const Interest >, Ptr< const Face > >	m_dropInterests
	trace of dropped Interests

TracedCallback< Ptr< const Data >, bool, Ptr< const Face > >	m_outData
	trace of outgoing Data

TracedCallback< Ptr< const Data >, Ptr< const Face > >	m_inData
	trace of incoming Data

TracedCallback< Ptr< const Data >, Ptr< const Face > >	m_dropData
	trace of dropped Data

TracedCallback< Ptr< const pit::Entry > >	m_satisfiedInterests

TracedCallback< Ptr< const pit::Entry > >	m_timedOutInterests

Detailed Description

Abstract base class for Ndn forwarding strategies.

Doxygen introspection did not find any typical Config paths.

Attributes

CacheUnsolicitedDataFromApps: Cache unsolicited data that has been pushed from applications
- Set with class: BooleanValue
- Underlying type: bool
- Initial value: true
- Flags: construct write read
CacheUnsolicitedData: Cache overheard data that have not been requested
- Set with class: BooleanValue
- Underlying type: bool
- Initial value: false
- Flags: construct write read
DetectRetransmissions: If non-duplicate interest is received on the same face more than once, it is considered a retransmission
- Set with class: BooleanValue
- Underlying type: bool
- Initial value: true
- Flags: construct write read

TraceSources

OutInterests: OutInterests
InInterests: InInterests
DropInterests: DropInterests
OutData: OutData
InData: InData
DropData: DropData
SatisfiedInterests: SatisfiedInterests
TimedOutInterests: TimedOutInterests

Definition at line 61 of file ndn-forwarding-strategy.h.

Member Function Documentation

void ns3::ndn::ForwardingStrategy::AddFace ( Ptr< Face > face )

virtual

Event fired every time face is added to NDN stack.

Parameters

face	face to be removed

Reimplemented in ns3::ndn::fw::PerOutFaceLimits< SmartFlooding >, ns3::ndn::fw::PerOutFaceLimits< BestRoute >, ns3::ndn::fw::PerOutFaceLimits< Flooding >, ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< SmartFlooding > >, ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< BestRoute > >, and ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< Flooding > >.

Definition at line 572 of file ndn-forwarding-strategy.cc.

bool ns3::ndn::ForwardingStrategy::CanSendOutInterest	(	Ptr< Face >	inFace,
		Ptr< Face >	outFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Method to check whether Interest can be send out on the particular face or not.

In the base class, this method perfoms two checks:

If inFace is equal to outFace (when equal, Interest forwarding is prohibited)
Whether Interest should be suppressed (list of outgoing faces include outFace), considering (if enabled) retransmission logic

Parameters

inFace	incoming face of the Interest
outFace	proposed outgoing face of the Interest
interest	Interest packet
pitEntry	reference to PIT entry (reference to corresponding FIB entry inside)

See also: DetectRetransmittedInterest

Reimplemented in ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< SmartFlooding > >, ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< BestRoute > >, ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< Flooding > >, ns3::ndn::fw::PerOutFaceLimits< SmartFlooding >, ns3::ndn::fw::PerOutFaceLimits< BestRoute >, and ns3::ndn::fw::PerOutFaceLimits< Flooding >.

Definition at line 493 of file ndn-forwarding-strategy.cc.

Referenced by TrySendOutInterest().

bool ns3::ndn::ForwardingStrategy::DetectRetransmittedInterest	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Method that implements logic to distinguish between new and retransmitted interest.

This method is called only when DetectRetransmissions attribute is set true (by default).

Currently, the retransmission detection logic relies on the fact that list of incoming faces already has inFace (i.e., a similar interest is received on the same face more than once).

Parameters

inFace	incoming face
interest	Interest header
pitEntry	an existing PIT entry, corresponding to the duplicated Interest

Returns: true if Interest should be considered as retransmitted

Definition at line 338 of file ndn-forwarding-strategy.cc.

Referenced by PropagateInterest(), and ShouldSuppressIncomingInterest().

void ns3::ndn::ForwardingStrategy::DidAddFibEntry ( Ptr< fib::Entry > fibEntry )

virtual

Event fired every time a FIB entry is added to FIB.

Parameters

fibEntry FIB entry that was added

Reimplemented in ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< SmartFlooding > >, ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< BestRoute > >, and ns3::ndn::fw::PerFibLimits< ::ns3::ndn::fw::PerOutFaceLimits< Flooding > >.

Definition at line 584 of file ndn-forwarding-strategy.cc.

void ns3::ndn::ForwardingStrategy::DidCreatePitEntry	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

An event that is fired every time a new PIT entry is created.

Note that if NDN node is receiving a similar interest (interest for the same name), then either DidReceiveDuplicateInterest, DidSuppressSimilarInterest, or DidForwardSimilarInterest will be called

Suppression of similar Interests is controlled using ShouldSuppressIncomingInterest virtual method

Parameters

inFace	incoming face
header	deserialized Interest header
pitEntry	created PIT entry (incoming and outgoing face sets are empty)

See also: DidReceiveDuplicateInterest, DidSuppressSimilarInterest, DidForwardSimilarInterest, ShouldSuppressIncomingInterest

Definition at line 273 of file ndn-forwarding-strategy.cc.

Referenced by OnInterest().

void ns3::ndn::ForwardingStrategy::DidExhaustForwardingOptions	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

An even that is fired when Interest cannot be forwarded.

Note that the event will not fire if retransmission detection is enabled (by default) and retransmitted Interest cannot by forwarded. For more details, refer to the implementation.

Parameters

inFace	incoming face
interest	Interest header
pitEntry	an existing PIT entry, corresponding to the duplicated Interest

See also: DetectRetransmittedInterest

Reimplemented in ns3::ndn::fw::Nacks.

Definition at line 315 of file ndn-forwarding-strategy.cc.

References m_dropInterests, and m_pit.

Referenced by ns3::ndn::fw::Nacks::DidExhaustForwardingOptions(), and PropagateInterest().

void ns3::ndn::ForwardingStrategy::DidForwardSimilarInterest	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

An event that is fired every time when a similar Interest is received and further forwarded (not suppressed/collapsed)

This even is fired just before handling the Interest to PropagateInterest method

Parameters

inFace	incoming face
interest	Interest packet
pitEntry	an existing PIT entry, corresponding to the duplicated Interest

See also: DidReceiveDuplicateInterest, DidSuppressSimilarInterest, ShouldSuppressIncomingInterest

Definition at line 308 of file ndn-forwarding-strategy.cc.

Referenced by OnInterest().

void ns3::ndn::ForwardingStrategy::DidReceiveDuplicateInterest	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

An event that is fired every time a duplicated Interest is received.

This even is the last action that is performed before the Interest processing is halted

Parameters

inFace	incoming face
interest	Interest packet
pitEntry	an existing PIT entry, corresponding to the duplicated Interest

See also: DidReceiveDuplicateInterest, DidSuppressSimilarInterest, DidForwardSimilarInterest, ShouldSuppressIncomingInterest

Reimplemented in ns3::ndn::fw::Nacks.

Definition at line 287 of file ndn-forwarding-strategy.cc.

References m_dropInterests.

Referenced by ns3::ndn::fw::Nacks::DidReceiveDuplicateInterest(), and OnInterest().

void ns3::ndn::ForwardingStrategy::DidReceiveSolicitedData	(	Ptr< Face >	inFace,
		Ptr< const Data >	data,
		bool	didCreateCacheEntry
	)

protectedvirtual

Event which is fired every time a requested (solicited) DATA packet (there is an active PIT entry) is received.

Parameters

inFace	incoming face
data	Data packet
didCreateCacheEntry	flag indicating whether a cache entry was added for this data packet or not (e.g., packet already exists in cache)

Definition at line 389 of file ndn-forwarding-strategy.cc.

Referenced by OnData().

void ns3::ndn::ForwardingStrategy::DidReceiveUnsolicitedData	(	Ptr< Face >	inFace,
		Ptr< const Data >	data,
		bool	didCreateCacheEntry
	)

protectedvirtual

Event which is fired every time an unsolicited DATA packet (no active PIT entry) is received.

The current implementation allows ignoring unsolicited DATA (by default), or cache it by setting attribute CacheUnsolicitedData true

Parameters

inFace	incoming face
data	Data packet
didCreateCacheEntry	flag indicating whether a cache entry was added for this data packet or not (e.g., packet already exists in cache)

Definition at line 397 of file ndn-forwarding-strategy.cc.

Referenced by OnData().

void ns3::ndn::ForwardingStrategy::DidSendOutData	(	Ptr< Face >	inFace,
		Ptr< Face >	outFace,
		Ptr< const Data >	data,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Event which is fired just after data was send out on the face.

Parameters

inFace	incoming face of the Data
outFace	outgoing face
data	Data packet
pitEntry	an existing PIT entry, corresponding to the duplicated Interest

Definition at line 557 of file ndn-forwarding-strategy.cc.

References m_outData.

Referenced by SatisfyPendingInterest().

void ns3::ndn::ForwardingStrategy::DidSendOutInterest	(	Ptr< Face >	inFace,
		Ptr< Face >	outFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Event fired just after forwarding the Interest.

Parameters

inFace	incoming face of the Interest
outFace	outgoing face of the Interest
interest	Interest packet
pitEntry	reference to PIT entry (reference to corresponding FIB entry inside)

Definition at line 548 of file ndn-forwarding-strategy.cc.

References m_outInterests.

Referenced by TrySendOutInterest().

void ns3::ndn::ForwardingStrategy::DidSuppressSimilarInterest	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

An event that is fired every time when a similar Interest is received and suppressed (collapsed)

This even is the last action that is performed before the Interest processing is halted

Parameters

inFace	incoming face
interest	Interest packet
pitEntry	an existing PIT entry, corresponding to the duplicated Interest

See also: DidReceiveDuplicateInterest, DidForwardSimilarInterest, ShouldSuppressIncomingInterest

Definition at line 301 of file ndn-forwarding-strategy.cc.

Referenced by OnInterest().

virtual bool ns3::ndn::ForwardingStrategy::DoPropagateInterest	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedpure virtual

Virtual method to perform Interest propagation according to the forwarding strategy logic.

In most cases, this is the call that needs to be implemented/re-implemented in order to perform forwarding of Interests according to the desired logic.

There is also PropagateInterest method (generally, do not require to be overriden) which performs general tasks (adding face to the list of incoming face, updating PIT entry lifetime, calling DoPropagateInterest, as well as perform retransmissions (enabled by default).

Parameters

inFace	incoming face
interest	Interest packet
pitEntry	reference to PIT entry (reference to corresponding FIB entry inside)

Returns: true if interest was successfully propagated, false if all options have failed

See also: PropagateInterest

Implemented in ns3::ndn::fw::Flooding, ns3::ndn::fw::BestRoute, ns3::ndn::fw::SmartFlooding, and ns3::ndn::fw::GreenYellowRed.

Referenced by PropagateInterest().

void ns3::ndn::ForwardingStrategy::FailedToCreatePitEntry	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest
	)

protectedvirtual

An event that is fired every time a new PIT entry cannot be created (e.g., PIT container imposes a limit)

Note that this call can be called only for non-similar Interest (i.e., there is an attempt to create a new PIT entry). For any non-similar Interests, either FailedToCreatePitEntry or DidCreatePitEntry is called.

Parameters

inFace	incoming face
interest	Interest packet

Definition at line 280 of file ndn-forwarding-strategy.cc.

References m_dropInterests.

Referenced by OnInterest().

void ns3::ndn::ForwardingStrategy::OnData	(	Ptr< Face >	face,
		Ptr< Data >	data
	)

virtual

Actual processing of incoming Ndn content objects.

Processing Data packets

Parameters

face	incoming face
data	Data packet

Definition at line 224 of file ndn-forwarding-strategy.cc.

References ns3::ndn::Face::APPLICATION, DidReceiveSolicitedData(), DidReceiveUnsolicitedData(), m_contentStore, m_dropData, m_inData, m_pit, SatisfyPendingInterest(), and WillSatisfyPendingInterest().

Referenced by ns3::ndn::L3Protocol::AddFace().

void ns3::ndn::ForwardingStrategy::OnInterest	(	Ptr< Face >	face,
		Ptr< Interest >	interest
	)

virtual

Actual processing of incoming Ndn interests.

Note, interests do not have payload

Processing Interest packets

Parameters

face	incoming face
interest	Interest packet

Reimplemented in ns3::ndn::fw::Nacks.

Definition at line 145 of file ndn-forwarding-strategy.cc.

References DidCreatePitEntry(), DidForwardSimilarInterest(), DidReceiveDuplicateInterest(), DidSuppressSimilarInterest(), FailedToCreatePitEntry(), m_contentStore, m_dropInterests, m_inInterests, m_pit, PropagateInterest(), SatisfyPendingInterest(), ShouldSuppressIncomingInterest(), and WillSatisfyPendingInterest().

Referenced by ns3::ndn::L3Protocol::AddFace(), and ns3::ndn::fw::Nacks::OnInterest().

void ns3::ndn::ForwardingStrategy::PropagateInterest	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Wrapper method, which performs general tasks and calls DoPropagateInterest method.

General tasks so far are adding face to the list of incoming face, updating PIT entry lifetime, calling DoPropagateInterest, and retransmissions (enabled by default).

Parameters

inFace	incoming face
interest	Interest packet
pitEntry	reference to PIT entry (reference to corresponding FIB entry inside)

See also: DoPropagateInterest

Todo:: Make lifetime per incoming interface

Definition at line 454 of file ndn-forwarding-strategy.cc.

References DetectRetransmittedInterest(), DidExhaustForwardingOptions(), and DoPropagateInterest().

Referenced by OnInterest().

void ns3::ndn::ForwardingStrategy::RemoveFace ( Ptr< Face > face )

virtual

Event fired every time face is removed from NDN stack.

Parameters

face	face to be removed

For example, when an application terminates, AppFace is removed and this method called by NDN stack.

Definition at line 578 of file ndn-forwarding-strategy.cc.

void ns3::ndn::ForwardingStrategy::SatisfyPendingInterest	(	Ptr< Face >	inFace,
		Ptr< const Data >	data,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Actual procedure to satisfy Interest.

Note that when Interest is satisfied from the cache, incoming face will be 0

Parameters

inFace	incoming face
data	Data packet
pitEntry	an existing PIT entry, corresponding to the duplicated Interest

Definition at line 356 of file ndn-forwarding-strategy.cc.

References DidSendOutData(), m_dropData, ns3::ndn::pit::IncomingFace::m_face, and m_pit.

Referenced by OnData(), and OnInterest().

bool ns3::ndn::ForwardingStrategy::ShouldSuppressIncomingInterest	(	Ptr< Face >	inFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Method implementing logic to suppress (collapse) similar Interests.

In the base class implementation this method checks list of incoming/outgoing faces of the PIT entry (for new Intersets, both lists are empty before this call)

For more details, refer to the source code.

Parameters

inFace	incoming face
interest	Interest packet
payload	Data payload

Definition at line 420 of file ndn-forwarding-strategy.cc.

References DetectRetransmittedInterest().

Referenced by OnInterest().

bool ns3::ndn::ForwardingStrategy::TrySendOutInterest	(	Ptr< Face >	inFace,
		Ptr< Face >	outFace,
		Ptr< const Interest >	interest,
		Ptr< pit::Entry >	pitEntry
	)

protectedvirtual

Method implementing actual interest forwarding, taking into account CanSendOutInterest decision.

If event returns false, then there is some kind of a problem exists

Parameters

inFace	incoming face of the Interest
outFace	proposed outgoing face of the Interest
interest	Interest packet
pitEntry	reference to PIT entry (reference to corresponding FIB entry inside)