NS-3 based Named Data Networking (NDN) simulator
ndnSIM 2.3: NDN, CCN, CCNx, content centric networks
API Documentation
algorithm.cpp
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1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2014-2017, 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.
10  *
11  * This file is part of NFD (Named Data Networking Forwarding Daemon).
12  * See AUTHORS.md for complete list of NFD authors and contributors.
13  *
14  * NFD is free software: you can redistribute it and/or modify it under the terms
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24  */
25 
26 #include "algorithm.hpp"
27 
28 namespace nfd {
29 namespace scope_prefix {
30 const Name LOCALHOST("ndn:/localhost");
31 const Name LOCALHOP("ndn:/localhop");
32 } // namespace scope_prefix
33 
34 namespace fw {
35 
36 bool
37 wouldViolateScope(const Face& inFace, const Interest& interest, const Face& outFace)
38 {
39  if (outFace.getScope() == ndn::nfd::FACE_SCOPE_LOCAL) {
40  // forwarding to a local face is always allowed
41  return false;
42  }
43 
44  if (scope_prefix::LOCALHOST.isPrefixOf(interest.getName())) {
45  // localhost Interests cannot be forwarded to a non-local face
46  return true;
47  }
48 
49  if (scope_prefix::LOCALHOP.isPrefixOf(interest.getName())) {
50  // localhop Interests can be forwarded to a non-local face only if it comes from a local face
51  return inFace.getScope() != ndn::nfd::FACE_SCOPE_LOCAL;
52  }
53 
54  // Interest name is not subject to scope control
55  return false;
56 }
57 
58 bool
59 canForwardToLegacy(const pit::Entry& pitEntry, const Face& face)
60 {
62 
63  bool hasUnexpiredOutRecord = std::any_of(pitEntry.out_begin(), pitEntry.out_end(),
64  [&face, &now] (const pit::OutRecord& outRecord) {
65  return &outRecord.getFace() == &face && outRecord.getExpiry() >= now;
66  });
67  if (hasUnexpiredOutRecord) {
68  return false;
69  }
70 
71  bool hasUnexpiredOtherInRecord = std::any_of(pitEntry.in_begin(), pitEntry.in_end(),
72  [&face, &now] (const pit::InRecord& inRecord) {
73  return &inRecord.getFace() != &face && inRecord.getExpiry() >= now;
74  });
75  if (!hasUnexpiredOtherInRecord) {
76  return false;
77  }
78 
79  return true;
80 }
81 
82 int
83 findDuplicateNonce(const pit::Entry& pitEntry, uint32_t nonce, const Face& face)
84 {
85  int dnw = DUPLICATE_NONCE_NONE;
86 
87  for (const pit::InRecord& inRecord : pitEntry.getInRecords()) {
88  if (inRecord.getLastNonce() == nonce) {
89  if (&inRecord.getFace() == &face) {
91  }
92  else {
94  }
95  }
96  }
97 
98  for (const pit::OutRecord& outRecord : pitEntry.getOutRecords()) {
99  if (outRecord.getLastNonce() == nonce) {
100  if (&outRecord.getFace() == &face) {
102  }
103  else {
105  }
106  }
107  }
108 
109  return dnw;
110 }
111 
112 bool
114 {
116  return std::any_of(pitEntry.out_begin(), pitEntry.out_end(),
117  [&now] (const pit::OutRecord& outRecord) {
118  return outRecord.getExpiry() >= now &&
119  outRecord.getIncomingNack() == nullptr;
120  });
121 }
122 
124 getLastOutgoing(const pit::Entry& pitEntry)
125 {
126  pit::OutRecordCollection::const_iterator lastOutgoing = std::max_element(
127  pitEntry.out_begin(), pitEntry.out_end(),
128  [] (const pit::OutRecord& a, const pit::OutRecord& b) {
129  return a.getLastRenewed() < b.getLastRenewed();
130  });
131  BOOST_ASSERT(lastOutgoing != pitEntry.out_end());
132 
133  return lastOutgoing->getLastRenewed();
134 }
135 
136 } // namespace fw
137 } // namespace nfd
bool canForwardToLegacy(const pit::Entry &pitEntry, const Face &face)
decide whether Interest can be forwarded to face
Definition: algorithm.cpp:59
time_point TimePoint
Definition: time.hpp:120
const Name & getName() const
Definition: interest.hpp:139
time::steady_clock::TimePoint getLastRenewed() const
const Name LOCALHOST("ndn:/localhost")
ndn:/localhost
Definition: algorithm.hpp:50
static time_point now() noexcept
Definition: time.cpp:80
contains information about an Interest from an incoming face
OutRecordCollection::iterator out_end()
Definition: pit-entry.hpp:189
represents an Interest packet
Definition: interest.hpp:42
const InRecordCollection & getInRecords() const
Definition: pit-entry.hpp:93
OutRecordCollection::iterator out_begin()
Definition: pit-entry.hpp:177
in-record of same face
Definition: algorithm.hpp:93
ndn Face
Definition: face-impl.hpp:41
InRecordCollection::iterator in_end()
Definition: pit-entry.hpp:122
Copyright (c) 2011-2015 Regents of the University of California.
Definition: ndn-common.hpp:40
an Interest table entry
Definition: pit-entry.hpp:57
Represents an absolute name.
Definition: name.hpp:42
const Name LOCALHOP("ndn:/localhop")
ndn:/localhop
Definition: algorithm.hpp:64
bool hasPendingOutRecords(const pit::Entry &pitEntry)
determine whether pitEntry has any pending out-records
Definition: algorithm.cpp:113
no duplicate Nonce is found
Definition: algorithm.hpp:92
time::steady_clock::TimePoint getLastOutgoing(const pit::Entry &pitEntry)
Definition: algorithm.cpp:124
int findDuplicateNonce(const pit::Entry &pitEntry, uint32_t nonce, const Face &face)
determine whether pitEntry has duplicate Nonce nonce
Definition: algorithm.cpp:83
InRecordCollection::iterator in_begin()
Definition: pit-entry.hpp:110
This file contains common algorithms used by forwarding strategies.
contains information about an Interest toward an outgoing face
in-record of other face
Definition: algorithm.hpp:94
out-record of other face
Definition: algorithm.hpp:96
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:37
const OutRecordCollection & getOutRecords() const
Definition: pit-entry.hpp:159
out-record of same face
Definition: algorithm.hpp:95