Self-learning strategy. More...

#include <self-learning-strategy.hpp>

Inheritance diagram for nfd::fw::SelfLearningStrategy:

Collaboration diagram for nfd::fw::SelfLearningStrategy:

[legend]

Classes
class	InRecordInfo
	StrategyInfo on pit::InRecord. More...

class	OutRecordInfo
	StrategyInfo on pit::OutRecord. More...

Public Member Functions
	SelfLearningStrategy (Forwarder &forwarder, const Name &name=getStrategyName())

void	afterReceiveInterest (const Face &inFace, const Interest &interest, const shared_ptr< pit::Entry > &pitEntry) override
	trigger after Interest is received More...

void	afterReceiveData (const shared_ptr< pit::Entry > &pitEntry, const Face &inFace, const Data &data) override
	trigger after Data is received More...

void	afterReceiveNack (const Face &inFace, const lp::Nack &nack, const shared_ptr< pit::Entry > &pitEntry) override
	trigger after Nack is received More...

Public Member Functions inherited from nfd::fw::Strategy
	Strategy (Forwarder &forwarder)
	construct a strategy instance More...

virtual	~Strategy ()

const Name &	getInstanceName () const

virtual void	beforeSatisfyInterest (const shared_ptr< pit::Entry > &pitEntry, const Face &inFace, const Data &data)
	trigger before PIT entry is satisfied More...

virtual void	afterContentStoreHit (const shared_ptr< pit::Entry > &pitEntry, const Face &inFace, const Data &data)
	trigger after a Data is matched in CS More...

virtual void	onDroppedInterest (const Face &outFace, const Interest &interest)
	trigger after Interest dropped for exceeding allowed retransmissions More...

Static Public Member Functions
static const Name &	getStrategyName ()

Static Public Member Functions inherited from nfd::fw::Strategy
template<typename S >
static void	registerType (const Name &strategyName=S::getStrategyName())
	register a strategy type More...

static bool	canCreate (const Name &instanceName)

static unique_ptr< Strategy >	create (const Name &instanceName, Forwarder &forwarder)

static bool	areSameType (const Name &instanceNameA, const Name &instanceNameB)

static std::set< Name >	listRegistered ()

static const Name &	getStrategyName ()

Additional Inherited Members
Protected Member Functions inherited from nfd::fw::Strategy
void	sendInterest (const shared_ptr< pit::Entry > &pitEntry, Face &outFace, const Interest &interest)
	send Interest to outFace More...

void	sendData (const shared_ptr< pit::Entry > &pitEntry, const Data &data, const Face &outFace)
	send `data` to `outFace` More...

void	sendDataToAll (const shared_ptr< pit::Entry > &pitEntry, const Face &inFace, const Data &data)
	send `data` to all matched and qualified faces More...

void	rejectPendingInterest (const shared_ptr< pit::Entry > &pitEntry)
	schedule the PIT entry for immediate deletion More...

void	sendNack (const shared_ptr< pit::Entry > &pitEntry, const Face &outFace, const lp::NackHeader &header)
	send Nack to outFace More...

void	sendNacks (const shared_ptr< pit::Entry > &pitEntry, const lp::NackHeader &header, std::initializer_list< const Face * > exceptFaces=std::initializer_list< const Face * >())
	send Nack to every face that has an in-record, except those in `exceptFaces` More...

void	setExpiryTimer (const shared_ptr< pit::Entry > &pitEntry, time::milliseconds duration)
	Schedule the PIT entry to be erased after `duration`. More...

const fib::Entry &	lookupFib (const pit::Entry &pitEntry) const
	performs a FIB lookup, considering Link object if present More...

MeasurementsAccessor &	getMeasurements ()

Face *	getFace (FaceId id) const

const FaceTable &	getFaceTable () const

void	setInstanceName (const Name &name)
	set strategy instance name More...

Static Protected Member Functions inherited from nfd::fw::Strategy
static ParsedInstanceName	parseInstanceName (const Name &input)
	parse a strategy instance name More...

static Name	makeInstanceName (const Name &input, const Name &strategyName)
	construct a strategy instance name More...

Protected Attributes inherited from nfd::fw::Strategy
signal::Signal< FaceTable, Face & > &	afterAddFace

signal::Signal< FaceTable, Face & > &	beforeRemoveFace

Detailed Description

Self-learning strategy.

This strategy first broadcasts Interest to learn a single path towards data, then unicasts subsequent Interests along the learned path

See also: https://redmine.named-data.net/attachments/864/Self-learning-strategy-v1.pdf

Definition at line 43 of file self-learning-strategy.hpp.

Constructor & Destructor Documentation

◆ SelfLearningStrategy()

nfd::fw::SelfLearningStrategy::SelfLearningStrategy	(	Forwarder &	forwarder,
		const Name &	name = `getStrategyName()`
	)

explicit

Definition at line 47 of file self-learning-strategy.cpp.

References getStrategyName(), nfd::fw::Strategy::makeInstanceName(), nfd::fw::Strategy::ParsedInstanceName::parameters, nfd::fw::Strategy::parseInstanceName(), nfd::fw::Strategy::setInstanceName(), ndn::to_string(), and nfd::fw::Strategy::ParsedInstanceName::version.

Member Function Documentation

◆ getStrategyName()

const Name & nfd::fw::SelfLearningStrategy::getStrategyName ( )

static

Definition at line 62 of file self-learning-strategy.cpp.

Referenced by SelfLearningStrategy().

◆ afterReceiveInterest()

void nfd::fw::SelfLearningStrategy::afterReceiveInterest	(	const Face &	inFace,
		const Interest &	interest,
		const shared_ptr< pit::Entry > &	pitEntry
	)

overridevirtual

trigger after Interest is received

The Interest:

does not violate Scope
is not looped
cannot be satisfied by ContentStore
is under a namespace managed by this strategy

The PIT entry is set to expire after InterestLifetime has elapsed at each downstream.

The strategy should decide whether and where to forward this Interest.

If the strategy decides to forward this Interest, invoke sendInterest for each upstream, either now or shortly after via a scheduler event, but before PIT entry expires. Optionally, the strategy can invoke setExpiryTimer to adjust how long it would wait for a response.
If the strategy has already forwarded this Interest previously and decides to continue waiting, do nothing. Optionally, the strategy can invoke setExpiryTimer to adjust how long it would wait for a response.
If the strategy concludes that this Interest cannot be satisfied, invoke rejectPendingInterest to erase the PIT entry.

Warning: The strategy must not retain shared_ptr<pit::Entry>, otherwise undefined behavior may occur. However, the strategy is allowed to store weak_ptr<pit::Entry>.

Implements nfd::fw::Strategy.

Definition at line 69 of file self-learning-strategy.cpp.

References nfd::face::Face::getId(), nfd::fib::Entry::getNextHops(), ndn::TagHost::getTag(), nfd::fw::Strategy::lookupFib(), NFD_LOG_DEBUG, nfd::fw::Strategy::rejectPendingInterest(), nfd::fw::Strategy::sendNack(), ndn::lp::NackHeader::setReason(), and ndn::TagHost::setTag().

◆ afterReceiveData()

void nfd::fw::SelfLearningStrategy::afterReceiveData	(	const shared_ptr< pit::Entry > &	pitEntry,
		const Face &	inFace,
		const Data &	data
	)

overridevirtual

trigger after Data is received

This trigger is invoked when an incoming Data satisfies exactly one PIT entry, and gives the strategy full control over Data forwarding.

When this trigger is invoked:

The Data has been verified to satisfy the PIT entry.
The PIT entry expiry timer is set to now

Within this function:

A strategy should return Data to downstream nodes via sendData or sendDataToAll.
A strategy can modify the Data as long as it still satisfies the PIT entry, such as adding or removing congestion marks.
A strategy can delay Data forwarding by prolonging the PIT entry lifetime via setExpiryTimer, and forward Data before the PIT entry is erased.
A strategy can collect measurements about the upstream.
A strategy can collect responses from additional upstream nodes by prolonging the PIT entry lifetime via setExpiryTimer every time a Data is received. Note that only one Data should be returned to each downstream node.

In the base class this method invokes beforeSatisfyInterest trigger and then returns the Data to downstream faces via sendDataToAll.

Reimplemented from nfd::fw::Strategy.

Definition at line 103 of file self-learning-strategy.cpp.

References ndn::TagHost::getTag(), nfd::fw::SelfLearningStrategy::OutRecordInfo::isNonDiscoveryInterest, and nfd::fw::Strategy::sendDataToAll().

◆ afterReceiveNack()

void nfd::fw::SelfLearningStrategy::afterReceiveNack	(	const Face &	inFace,
		const lp::Nack &	nack,
		const shared_ptr< pit::Entry > &	pitEntry
	)

overridevirtual

trigger after Nack is received

This trigger is invoked when an incoming Nack is received in response to an forwarded Interest. The Nack has been confirmed to be a response to the last Interest forwarded to that upstream, i.e. the PIT out-record exists and has a matching Nonce. The NackHeader has been recorded in the PIT out-record.

If the PIT entry is not yet satisfied, its expiry timer remains unchanged. Otherwise, the PIT entry normally would expire immediately after this function returns.

If the strategy wishes to collect responses from additional upstream nodes, it should invoke setExpiryTimer within this function to retain the PIT entry. If a Nack arrives from another upstream during the extended PIT entry lifetime, this trigger will be invoked again. At that time, this function must invoke setExpiryTimer again to continue collecting more responses.

In the base class this method does nothing.

Warning: The strategy must not retain shared_ptr<pit::Entry>, otherwise undefined behavior may occur. However, the strategy is allowed to store weak_ptr<pit::Entry>.

Reimplemented from nfd::fw::Strategy.

Definition at line 127 of file self-learning-strategy.cpp.

References ndn::lp::Nack::getHeader(), nfd::face::Face::getId(), ndn::lp::Nack::getInterest(), ndn::Interest::getName(), ndn::lp::Nack::getReason(), nfd::fib::Entry::hasNextHops(), nfd::fw::Strategy::lookupFib(), NFD_LOG_DEBUG, and nfd::fw::Strategy::sendNacks().

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

ndnSIM/NFD/daemon/fw/self-learning-strategy.hpp
ndnSIM/NFD/daemon/fw/self-learning-strategy.cpp

Classes

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ SelfLearningStrategy()

Member Function Documentation

◆ getStrategyName()

◆ afterReceiveInterest()

◆ afterReceiveData()

◆ afterReceiveNack()