multicast-strategy.cpp
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3  * Copyright (c) 2014-2019, Regents of the University of California,
4  * Arizona Board of Regents,
5  * Colorado State University,
6  * University Pierre & Marie Curie, Sorbonne University,
7  * Washington University in St. Louis,
8  * Beijing Institute of Technology,
9  * The University of Memphis.
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11  * This file is part of NFD (Named Data Networking Forwarding Daemon).
12  * See AUTHORS.md for complete list of NFD authors and contributors.
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25 
26 #include "multicast-strategy.hpp"
27 #include "algorithm.hpp"
28 #include "common/logger.hpp"
29 
30 namespace nfd {
31 namespace fw {
32 
33 NFD_REGISTER_STRATEGY(MulticastStrategy);
34 
35 NFD_LOG_INIT(MulticastStrategy);
36 
37 const time::milliseconds MulticastStrategy::RETX_SUPPRESSION_INITIAL(10);
38 const time::milliseconds MulticastStrategy::RETX_SUPPRESSION_MAX(250);
39 
40 MulticastStrategy::MulticastStrategy(Forwarder& forwarder, const Name& name)
41  : Strategy(forwarder)
42  , ProcessNackTraits(this)
43  , m_retxSuppression(RETX_SUPPRESSION_INITIAL,
44  RetxSuppressionExponential::DEFAULT_MULTIPLIER,
45  RETX_SUPPRESSION_MAX)
46 {
48  if (!parsed.parameters.empty()) {
49  NDN_THROW(std::invalid_argument("MulticastStrategy does not accept parameters"));
50  }
51  if (parsed.version && *parsed.version != getStrategyName()[-1].toVersion()) {
52  NDN_THROW(std::invalid_argument(
53  "MulticastStrategy does not support version " + to_string(*parsed.version)));
54  }
56 }
57 
58 const Name&
60 {
61  static Name strategyName("/localhost/nfd/strategy/multicast/%FD%03");
62  return strategyName;
63 }
64 
65 void
66 MulticastStrategy::afterReceiveInterest(const FaceEndpoint& ingress, const Interest& interest,
67  const shared_ptr<pit::Entry>& pitEntry)
68 {
69  const fib::Entry& fibEntry = this->lookupFib(*pitEntry);
70  const fib::NextHopList& nexthops = fibEntry.getNextHops();
71 
72  int nEligibleNextHops = 0;
73 
74  bool isSuppressed = false;
75 
76  for (const auto& nexthop : nexthops) {
77  Face& outFace = nexthop.getFace();
78 
79  RetxSuppressionResult suppressResult = m_retxSuppression.decidePerUpstream(*pitEntry, outFace);
80 
81  if (suppressResult == RetxSuppressionResult::SUPPRESS) {
82  NFD_LOG_DEBUG(interest << " from=" << ingress << " to=" << outFace.getId() << " suppressed");
83  isSuppressed = true;
84  continue;
85  }
86 
87  if ((outFace.getId() == ingress.face.getId() && outFace.getLinkType() != ndn::nfd::LINK_TYPE_AD_HOC) ||
88  wouldViolateScope(ingress.face, interest, outFace)) {
89  continue;
90  }
91 
92  this->sendInterest(pitEntry, FaceEndpoint(outFace, 0), interest);
93  NFD_LOG_DEBUG(interest << " from=" << ingress << " pitEntry-to=" << outFace.getId());
94 
95  if (suppressResult == RetxSuppressionResult::FORWARD) {
96  m_retxSuppression.incrementIntervalForOutRecord(*pitEntry->getOutRecord(outFace));
97  }
98  ++nEligibleNextHops;
99  }
100 
101  if (nEligibleNextHops == 0 && !isSuppressed) {
102  NFD_LOG_DEBUG(interest << " from=" << ingress << " noNextHop");
103 
104  lp::NackHeader nackHeader;
105  nackHeader.setReason(lp::NackReason::NO_ROUTE);
106  this->sendNack(pitEntry, ingress, nackHeader);
107 
108  this->rejectPendingInterest(pitEntry);
109  }
110 }
111 
112 void
113 MulticastStrategy::afterReceiveNack(const FaceEndpoint& ingress, const lp::Nack& nack,
114  const shared_ptr<pit::Entry>& pitEntry)
115 {
116  this->processNack(ingress.face, nack, pitEntry);
117 }
118 
119 } // namespace fw
120 } // namespace nfd
Main class of NFD&#39;s forwarding engine.
Definition: forwarder.hpp:51
Interest is retransmission and should be forwarded.
void setInstanceName(const Name &name)
set strategy instance name
Definition: strategy.hpp:382
void incrementIntervalForOutRecord(pit::OutRecord &outRecord)
Increment the suppression interval for out record.
void sendNack(const shared_ptr< pit::Entry > &pitEntry, const FaceEndpoint &egress, const lp::NackHeader &header)
send Nack to egress
Definition: strategy.hpp:302
represents a FIB entry
Definition: fib-entry.hpp:53
Interest is retransmission and should be suppressed.
static Name makeInstanceName(const Name &input, const Name &strategyName)
construct a strategy instance name
Definition: strategy.cpp:134
RetxSuppressionResult decidePerUpstream(pit::Entry &pitEntry, Face &outFace)
determines whether Interest is a retransmission per upstream and if so, whether it shall be forwarded...
static const Name & getStrategyName()
void sendInterest(const shared_ptr< pit::Entry > &pitEntry, const FaceEndpoint &egress, const Interest &interest)
send Interest to egress
Definition: strategy.cpp:197
Represents a face-endpoint pair in the forwarder.
Copyright (c) 2014-2015, Regents of the University of California, Arizona Board of Regents...
Definition: algorithm.hpp:32
a retransmission suppression decision algorithm that suppresses retransmissions using exponential bac...
MulticastStrategy(Forwarder &forwarder, const Name &name=getStrategyName())
void afterReceiveInterest(const FaceEndpoint &ingress, const Interest &interest, const shared_ptr< pit::Entry > &pitEntry) override
trigger after Interest is received
Represents a collection of nexthops.
Definition: fib-entry.hpp:39
PartialName parameters
parameter components
Definition: strategy.hpp:355
represents a forwarding strategy
Definition: strategy.hpp:37
This file contains common algorithms used by forwarding strategies.
#define NFD_LOG_DEBUG
Definition: logger.hpp:38
#define NFD_LOG_INIT(name)
Definition: logger.hpp:31
static ParsedInstanceName parseInstanceName(const Name &input)
parse a strategy instance name
Definition: strategy.cpp:123
void afterReceiveNack(const FaceEndpoint &ingress, const lp::Nack &nack, const shared_ptr< pit::Entry > &pitEntry) override
trigger after Nack is received
void processNack(const Face &inFace, const lp::Nack &nack, const shared_ptr< pit::Entry > &pitEntry)
NFD_REGISTER_STRATEGY(SelfLearningStrategy)
bool wouldViolateScope(const Face &inFace, const Interest &interest, const Face &outFace)
determine whether forwarding the Interest in pitEntry to outFace would violate scope ...
Definition: algorithm.cpp:32
const NextHopList & getNextHops() const
Definition: fib-entry.hpp:66
void rejectPendingInterest(const shared_ptr< pit::Entry > &pitEntry)
schedule the PIT entry for immediate deletion
Definition: strategy.hpp:289
const fib::Entry & lookupFib(const pit::Entry &pitEntry) const
performs a FIB lookup, considering Link object if present
Definition: strategy.cpp:288
optional< uint64_t > version
whether strategyName contains a version component
Definition: strategy.hpp:354