Best Route strategy version 4. More...

#include <best-route-strategy2.hpp>

Inheritance diagram for nfd::fw::BestRouteStrategy2:

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Collaboration diagram for nfd::fw::BestRouteStrategy2:

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Public Member Functions
	BestRouteStrategy2 (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	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	afterReceiveData (const shared_ptr< pit::Entry > &pitEntry, const Face &inFace, const Data &data)
	trigger after Data is received 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...

Protected Member Functions inherited from nfd::fw::ProcessNackTraits< BestRouteStrategy2 >
	ProcessNackTraits (BestRouteStrategy2 *strategy)

Protected Member Functions inherited from nfd::fw::ProcessNackTraitsBase
virtual	~ProcessNackTraitsBase ()=default

void	processNack (const Face &inFace, const lp::Nack &nack, const shared_ptr< pit::Entry > &pitEntry)

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

Best Route strategy version 4.

This strategy forwards a new Interest to the lowest-cost nexthop (except downstream). After that, if consumer retransmits the Interest (and is not suppressed according to exponential backoff algorithm), the strategy forwards the Interest again to the lowest-cost nexthop (except downstream) that is not previously used. If all nexthops have been used, the strategy starts over with the first nexthop.

This strategy returns Nack to all downstreams with reason NoRoute if there is no usable nexthop, which may be caused by: (a) the FIB entry contains no nexthop; (b) the FIB nexthop happens to be the sole downstream; (c) the FIB nexthops violate scope.

This strategy returns Nack to all downstreams if all upstreams have returned Nacks. The reason of the sent Nack equals the least severe reason among received Nacks.

Definition at line 53 of file best-route-strategy2.hpp.

Constructor & Destructor Documentation

◆ BestRouteStrategy2()

nfd::fw::BestRouteStrategy2::BestRouteStrategy2	(	Forwarder &	forwarder,
		const Name &	name = `getStrategyName()`
	)

explicit

Definition at line 39 of file best-route-strategy2.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::BestRouteStrategy2::getStrategyName ( )

static

Definition at line 58 of file best-route-strategy2.cpp.

Referenced by BestRouteStrategy2(), and nfd::getDefaultStrategyName().

◆ afterReceiveInterest()

void nfd::fw::BestRouteStrategy2::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 127 of file best-route-strategy2.cpp.

References nfd::fw::RetxSuppressionExponential::decidePerPitEntry(), nfd::fw::findEligibleNextHopWithEarliestOutRecord(), nfd::face::Face::getId(), nfd::fib::Entry::getNextHops(), nfd::fw::isNextHopEligible(), nfd::fw::Strategy::lookupFib(), nfd::fw::NEW, NFD_LOG_DEBUG, ndn::time::steady_clock::now(), nfd::fw::Strategy::rejectPendingInterest(), nfd::fw::Strategy::sendInterest(), nfd::fw::Strategy::sendNack(), ndn::lp::NackHeader::setReason(), and nfd::fw::SUPPRESS.

◆ afterReceiveNack()

void nfd::fw::BestRouteStrategy2::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 192 of file best-route-strategy2.cpp.

References nfd::fw::ProcessNackTraitsBase::processNack().

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

ndnSIM/NFD/daemon/fw/best-route-strategy2.hpp
ndnSIM/NFD/daemon/fw/best-route-strategy2.cpp

Public Member Functions

Static Public Member Functions