NS-3 based Named Data Networking (NDN) simulator
ndnSIM 2.5: NDN, CCN, CCNx, content centric networks
API Documentation
lp-reliability.hpp
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25 
26 #ifndef NFD_DAEMON_FACE_LP_RELIABILITY_HPP
27 #define NFD_DAEMON_FACE_LP_RELIABILITY_HPP
28 
29 #include "core/rtt-estimator.hpp"
30 #include "core/scheduler.hpp"
31 
32 #include <ndn-cxx/lp/packet.hpp>
33 #include <ndn-cxx/lp/sequence.hpp>
34 
35 #include <queue>
36 
37 namespace nfd {
38 namespace face {
39 
40 class GenericLinkService;
41 
45 class LpReliability : noncopyable
46 {
47 public:
48  struct Options
49  {
52  bool isEnabled = false;
53 
56  size_t maxRetx = 3;
57 
60  time::nanoseconds idleAckTimerPeriod = 5_ms;
61 
65  size_t seqNumLossThreshold = 3;
66  };
67 
68  LpReliability(const Options& options, GenericLinkService* linkService);
69 
73 
76  void
77  setOptions(const Options& options);
78 
83  const GenericLinkService*
84  getLinkService() const;
85 
91  void
92  handleOutgoing(std::vector<lp::Packet>& frags, lp::Packet&& pkt, bool isInterest);
93 
97  void
99 
104  void
105  piggyback(lp::Packet& pkt, ssize_t mtu);
106 
108  class UnackedFrag;
109  class NetPkt;
110  using UnackedFrags = std::map<lp::Sequence, UnackedFrag>;
111 
119  assignTxSequence(lp::Packet& frag);
120 
127  void
128  startIdleAckTimer();
129 
132  void
133  stopIdleAckTimer();
134 
140  std::vector<lp::Sequence>
141  findLostLpPackets(UnackedFrags::iterator ackIt);
142 
146  std::vector<lp::Sequence>
147  onLpPacketLost(lp::Sequence txSeq);
148 
156  void
157  onLpPacketAcknowledged(UnackedFrags::iterator fragIt);
158 
166  void
167  deleteUnackedFrag(UnackedFrags::iterator fragIt);
168 
172  class UnackedFrag
173  {
174  public:
175  explicit
176  UnackedFrag(lp::Packet pkt);
177 
178  public:
179  lp::Packet pkt;
180  scheduler::ScopedEventId rtoTimer;
182  size_t retxCount;
183  size_t nGreaterSeqAcks;
184  shared_ptr<NetPkt> netPkt;
185  };
186 
189  class NetPkt
190  {
191  public:
192  NetPkt(lp::Packet&& pkt, bool isInterest);
193 
194  public:
195  std::vector<UnackedFrags::iterator> unackedFrags;
196  lp::Packet pkt;
197  bool isInterest;
198  bool didRetx;
199  };
200 
201 public:
203  static constexpr size_t RESERVED_HEADER_SPACE = 3 + 1 + sizeof(lp::Sequence);
204 
206  Options m_options;
207  GenericLinkService* m_linkService;
208  UnackedFrags m_unackedFrags;
214  UnackedFrags::iterator m_firstUnackedFrag;
215  std::queue<lp::Sequence> m_ackQueue;
216  lp::Sequence m_lastTxSeqNo;
217  scheduler::ScopedEventId m_idleAckTimer;
218  bool m_isIdleAckTimerRunning;
219  RttEstimator m_rto;
220 };
221 
222 } // namespace face
223 } // namespace nfd
224 
225 #endif // NFD_DAEMON_FACE_LP_RELIABILITY_HPP
#define PUBLIC_WITH_TESTS_ELSE_PRIVATE
Definition: common.hpp:40
size_t maxRetx
maximum number of retransmissions for an LpPacket
time_point TimePoint
Definition: time.hpp:225
void setOptions(const Options &options)
set options for reliability
GenericLinkService is a LinkService that implements the NDNLPv2 protocol.
void processIncomingPacket(const lp::Packet &pkt)
extract and parse all Acks and add Ack for contained Fragment (if any) to AckQueue
void piggyback(lp::Packet &pkt, ssize_t mtu)
called by GenericLinkService to attach Acks onto an outgoing LpPacket
void handleOutgoing(std::vector< lp::Packet > &frags, lp::Packet &&pkt, bool isInterest)
observe outgoing fragment(s) of a network packet and store for potential retransmission
provides a lightweight signal / event system
Definition: signal.hpp:51
bool isEnabled
enables link-layer reliability
uint64_t Sequence
represents a sequence number
Definition: sequence.hpp:35
static constexpr size_t RESERVED_HEADER_SPACE
TxSequence TLV-TYPE (3 octets) + TxSequence TLV-LENGTH (1 octet) + sizeof(lp::Sequence)
Table::const_iterator iterator
Definition: cs-internal.hpp:41
size_t seqNumLossThreshold
a fragment is considered lost if this number of fragments with greater sequence numbers are acknowled...
Copyright (c) 2011-2015 Regents of the University of California.
Definition: ndn-common.hpp:40
const GenericLinkService * getLinkService() const
LpReliability(const Options &options, GenericLinkService *linkService)
A scoped handle of scheduled event.
Definition: scheduler.hpp:123
implements the Mean-Deviation RTT estimator
signal::Signal< LpReliability, Interest > onDroppedInterest
signals on Interest dropped by reliability system for exceeding allowed number of retx
time::nanoseconds idleAckTimerPeriod
period between sending pending Acks in an IDLE packet
provides for reliable sending and receiving of link-layer packets