fw: Adaptive SRTT-based Forwarding strategy

refs: #3566

Change-Id: Idae198bb0c2ae25e25aeceec0552b1c11be89c14
diff --git a/daemon/fw/asf-probing-module.hpp b/daemon/fw/asf-probing-module.hpp
new file mode 100644
index 0000000..a10b1f8
--- /dev/null
+++ b/daemon/fw/asf-probing-module.hpp
@@ -0,0 +1,85 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2016,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NFD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef NFD_DAEMON_FW_ASF_PROBING_MODULE_HPP
+#define NFD_DAEMON_FW_ASF_PROBING_MODULE_HPP
+
+#include "asf-measurements.hpp"
+
+namespace nfd {
+namespace fw {
+namespace asf {
+
+/** \brief ASF Probing Module
+ */
+class ProbingModule
+{
+public:
+  explicit
+  ProbingModule(AsfMeasurements& measurements);
+
+  void
+  scheduleProbe(shared_ptr<fib::Entry> fibEntry, const time::milliseconds& interval);
+
+  shared_ptr<Face>
+  getFaceToProbe(const Face& inFace,
+                 const Interest& interest,
+                 shared_ptr<fib::Entry> fibEntry,
+                 const Face& faceUsed);
+
+  bool
+  isProbingNeeded(shared_ptr<fib::Entry> fibEntry, const ndn::Interest& interest);
+
+  void
+  afterForwardingProbe(shared_ptr<fib::Entry> fibEntry, const ndn::Interest& interest);
+
+private:
+  // Used to associate FaceInfo with the face in a NextHop
+  typedef std::pair<FaceInfo*, shared_ptr<Face>> FaceInfoFacePair;
+  typedef std::function<bool(FaceInfoFacePair, FaceInfoFacePair)> FaceInfoPredicate;
+  typedef std::set<FaceInfoFacePair, FaceInfoPredicate> FaceInfoFacePairSet;
+
+  shared_ptr<Face>
+  getFaceBasedOnProbability(const FaceInfoFacePairSet& rankedFaces);
+
+  double
+  getProbingProbability(uint64_t rank, uint64_t rankSum, uint64_t nFaces);
+
+  double
+  getRandomNumber(double start, double end);
+
+public:
+  static constexpr time::seconds DEFAULT_PROBING_INTERVAL = time::seconds(60);
+
+private:
+  time::seconds m_probingInterval;
+  AsfMeasurements& m_measurements;
+};
+
+} // namespace asf
+} // namespace fw
+} // namespace nfd
+
+#endif // NFD_DAEMON_FW_ASF_PROBING_MODULE_HPP