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 = time::milliseconds(5);
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<UnackedFrags::iterator>
141  findLostLpPackets(UnackedFrags::iterator ackIt);
142 
145  void
146  onLpPacketLost(UnackedFrags::iterator txSeqIt);
147 
155  void
156  onLpPacketAcknowledged(UnackedFrags::iterator fragIt);
157 
165  void
166  deleteUnackedFrag(UnackedFrags::iterator fragIt);
167 
171  class UnackedFrag
172  {
173  public:
174  explicit
175  UnackedFrag(lp::Packet pkt);
176 
177  public:
178  lp::Packet pkt;
179  scheduler::ScopedEventId rtoTimer;
181  size_t retxCount;
182  size_t nGreaterSeqAcks;
183  shared_ptr<NetPkt> netPkt;
184  };
185 
188  class NetPkt
189  {
190  public:
191  NetPkt(lp::Packet&& pkt, bool isInterest);
192 
193  public:
194  std::vector<UnackedFrags::iterator> unackedFrags;
195  lp::Packet pkt;
196  bool isInterest;
197  bool didRetx;
198  };
199 
200 public:
202  static constexpr size_t RESERVED_HEADER_SPACE = 3 + 1 + sizeof(lp::Sequence);
203 
205  Options m_options;
206  GenericLinkService* m_linkService;
207  UnackedFrags m_unackedFrags;
213  UnackedFrags::iterator m_firstUnackedFrag;
214  std::queue<lp::Sequence> m_ackQueue;
215  lp::Sequence m_lastTxSeqNo;
216  scheduler::ScopedEventId m_idleAckTimer;
217  bool m_isIdleAckTimerRunning;
218  RttEstimator m_rto;
219 };
220 
221 } // namespace face
222 } // namespace nfd
223 
224 #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:226
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:50
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
cancels an event automatically upon destruction
Definition: scheduler.hpp:59
LpReliability(const Options &options, GenericLinkService *linkService)
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