model/ccnx-l3-protocol.cc - ndnSIM - Gitiles

 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
 /*
  * Copyright (c) 2011 University of California, Los Angeles
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation;
  *
  * This program 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 this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  *
  * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
  *         Ilya Moiseenko <iliamo@cs.ucla.edu>
  */

 #include "ccnx-l3-protocol.h"

 #include "ns3/packet.h"
 #include "ns3/node.h"
 #include "ns3/log.h"
 #include "ns3/callback.h"
 #include "ns3/uinteger.h"
 #include "ns3/trace-source-accessor.h"
 #include "ns3/object-vector.h"
 #include "ns3/boolean.h"

 #include "ns3/ccnx-header-helper.h"

 #include "ccnx-face.h"
 #include "ccnx-forwarding-strategy.h"
 #include "ccnx-interest-header.h"
 #include "ccnx-content-object-header.h"

 #include "ccnx-net-device-face.h"

 #include <boost/foreach.hpp>
 #include <boost/lambda/lambda.hpp>
 #include <boost/lambda/bind.hpp>

 using namespace boost::tuples;
 namespace ll = boost::lambda;

 NS_LOG_COMPONENT_DEFINE ("CcnxL3Protocol");

 namespace ns3 {

 const uint16_t CcnxL3Protocol::ETHERNET_FRAME_TYPE = 0x7777;

 NS_OBJECT_ENSURE_REGISTERED (CcnxL3Protocol);

 TypeId
 CcnxL3Protocol::GetTypeId (void)
 {
   static TypeId tid = TypeId ("ns3::CcnxL3Protocol")
     .SetParent<Ccnx> ()
     .SetGroupName ("Ccnx")
     .AddConstructor<CcnxL3Protocol> ()
     .AddAttribute ("BucketLeakInterval",
                    "Interval to leak buckets",
                    StringValue ("10ms"),
                    MakeTimeAccessor (&CcnxL3Protocol::GetBucketLeakInterval,
                                      &CcnxL3Protocol::SetBucketLeakInterval),
                    MakeTimeChecker ())
   ;
   return tid;
 }

 CcnxL3Protocol::CcnxL3Protocol()
 : m_faceCounter (0)
 {
   NS_LOG_FUNCTION (this);

   m_pit = CreateObject<CcnxPit> ();
   m_contentStore = CreateObject<CcnxContentStore> ();
 }

 CcnxL3Protocol::~CcnxL3Protocol ()
 {
   NS_LOG_FUNCTION (this);
 }

 void
 CcnxL3Protocol::SetNode (Ptr<Node> node)
 {
   m_node = node;
   m_fib = m_node->GetObject<CcnxFib> ();
   NS_ASSERT_MSG (m_fib != 0, "FIB should be created and aggregated to a node before calling Ccnx::SetNode");

   m_pit->SetFib (m_fib);
 }

 /*
  * This method is called by AddAgregate and completes the aggregation
  * by setting the node in the ccnx stack
  */
 void
 CcnxL3Protocol::NotifyNewAggregate ()
 {
   if (m_node == 0)
     {
       Ptr<Node>node = this->GetObject<Node>();
       // verify that it's a valid node and that
       // the node has not been set before
       if (node != 0)
         {
           this->SetNode (node);
         }
     }
   Object::NotifyNewAggregate ();
 }

 void
 CcnxL3Protocol::DoDispose (void)
 {
   NS_LOG_FUNCTION (this);

   if (m_bucketLeakEvent.IsRunning ())
     m_bucketLeakEvent.Cancel ();

   for (CcnxFaceList::iterator i = m_faces.begin (); i != m_faces.end (); ++i)
     {
       *i = 0;
     }
   m_faces.clear ();
   m_node = 0;

   // Force delete on objects
   m_forwardingStrategy = 0; // there is a reference to PIT stored in here
   m_pit = 0;
   m_contentStore = 0;
   m_fib = 0;

   // m_forwardingStrategy = 0;
   Object::DoDispose ();
 }

 void
 CcnxL3Protocol::SetForwardingStrategy (Ptr<CcnxForwardingStrategy> forwardingStrategy)
 {
   NS_LOG_FUNCTION (this);
   m_forwardingStrategy = forwardingStrategy;
   m_forwardingStrategy->SetPit (m_pit);
 }

 Ptr<CcnxForwardingStrategy>
 CcnxL3Protocol::GetForwardingStrategy (void) const
 {
   return m_forwardingStrategy;
 }

 uint32_t
 CcnxL3Protocol::AddFace (const Ptr<CcnxFace> &face)
 {
   NS_LOG_FUNCTION (this << &face);

   face->SetId (m_faceCounter); // sets a unique ID of the face. This ID serves only informational purposes

   // ask face to register in lower-layer stack
   face->RegisterProtocolHandler (MakeCallback (&CcnxL3Protocol::Receive, this));

   m_faces.push_back (face);
   m_faceCounter++;
   return face->GetId ();
 }

 void
 CcnxL3Protocol::RemoveFace (Ptr<CcnxFace> face)
 {
   // ask face to register in lower-layer stack
   face->RegisterProtocolHandler (MakeNullCallback<void,const Ptr<CcnxFace>&,const Ptr<const Packet>&> ());

   // just to be on a safe side. Do the process in two steps
   std::list<CcnxPitEntryContainer::type::iterator> entriesToRemoves;
   BOOST_FOREACH (const CcnxPitEntry &pitEntry, *m_pit)
     {
       m_pit->modify (m_pit->iterator_to (pitEntry),
                      ll::bind (&CcnxPitEntry::RemoveAllReferencesToFace, ll::_1, face));

       // If this face is the only for the associated FIB entry, then FIB entry will be removed soon.
       // Thus, we have to remove the whole PIT entry
       if (pitEntry.m_fibEntry.m_faces.size () == 1 &&
           pitEntry.m_fibEntry.m_faces.begin ()->m_face == face)
         {
           entriesToRemoves.push_back (m_pit->iterator_to (pitEntry));
         }
     }
   BOOST_FOREACH (CcnxPitEntryContainer::type::iterator entry, entriesToRemoves)
     {
       m_pit->erase (entry);
     }

   CcnxFaceList::iterator face_it = find (m_faces.begin(), m_faces.end(), face);
   NS_ASSERT_MSG (face_it != m_faces.end (), "Attempt to remove face that doesn't exist");
   m_faces.erase (face_it);
 }

 Ptr<CcnxFace>
 CcnxL3Protocol::GetFace (uint32_t index) const
 {
   BOOST_FOREACH (const Ptr<CcnxFace> &face, m_faces) // this function is not supposed to be called often, so linear search is fine
     {
       if (face->GetId () == index)
         return face;
     }
   return 0;
 }

 Ptr<CcnxFace>
 CcnxL3Protocol::GetFaceByNetDevice (Ptr<NetDevice> netDevice) const
 {
   BOOST_FOREACH (const Ptr<CcnxFace> &face, m_faces) // this function is not supposed to be called often, so linear search is fine
     {
       Ptr<CcnxNetDeviceFace> netDeviceFace = DynamicCast<CcnxNetDeviceFace> (face);
       if (netDeviceFace == 0) continue;

       if (netDeviceFace->GetNetDevice () == netDevice)
         return face;
     }
   return 0;
 }

 uint32_t
 CcnxL3Protocol::GetNFaces (void) const
 {
   return m_faces.size ();
 }

 // Callback from lower layer
 void
 CcnxL3Protocol::Receive (const Ptr<CcnxFace> &face, const Ptr<const Packet> &p)
 {
   if (!face->IsUp ())
     {
       NS_LOG_LOGIC ("Dropping received packet -- interface is down");
       // m_dropTrace (p, INTERFACE_DOWN, m_node->GetObject<Ccnx> ()/*this*/, face);
       return;
     }
   NS_LOG_LOGIC ("Packet from face " << *face << " received on node " <<  m_node->GetId ());

   Ptr<Packet> packet = p->Copy (); // give upper layers a rw copy of the packet
   try
     {
       CcnxHeaderHelper::Type type = CcnxHeaderHelper::GetCcnxHeaderType (p);
       switch (type)
         {
         case CcnxHeaderHelper::INTEREST:
           {
             Ptr<CcnxInterestHeader> header = Create<CcnxInterestHeader> ();

             // Deserialization. Exception may be thrown
             packet->RemoveHeader (*header);
             NS_ASSERT_MSG (packet->GetSize () == 0, "Payload of Interests should be zero");

             if (header->GetNack () > 0)
               OnNack (face, header, p/*original packet*/);
             else
               OnInterest (face, header, p/*original packet*/);
             break;
           }
         case CcnxHeaderHelper::CONTENT_OBJECT:
           {
             Ptr<CcnxContentObjectHeader> header = Create<CcnxContentObjectHeader> ();

             static CcnxContentObjectTail contentObjectTrailer; //there is no data in this object

             // Deserialization. Exception may be thrown
             packet->RemoveHeader (*header);
             packet->RemoveTrailer (contentObjectTrailer);

             OnData (face, header, packet/*payload*/, p/*original packet*/);
             break;
           }
         }

       // exception will be thrown if packet is not recognized
     }
   catch (CcnxUnknownHeaderException)
     {
       NS_ASSERT_MSG (false, "Unknown CCNx header. Should not happen");
     }
 }

 void
 CcnxL3Protocol::OnNack (const Ptr<CcnxFace> &incomingFace,
                         Ptr<CcnxInterestHeader> &header,
                         const Ptr<const Packet> &packet)
 {
   NS_LOG_FUNCTION (incomingFace << header << packet);

   tuple<const CcnxPitEntry&,bool,bool> ret = m_pit->Lookup (*header);
   CcnxPitEntry const& pitEntry = ret.get<0> ();
   bool isNew = ret.get<1> ();
   //bool isDuplicated = ret.get<2> ();

   // NS_ASSERT_MSG (isDuplicated,
   //                "NACK should be a duplicated interest");
   if (isNew /*|| !isDuplicated*/) // potential flow
     {
       // somebody is doing something bad
       NS_ASSERT (false); // temporary assert
       return;
     }

   // CcnxPitEntryIncomingFaceContainer::type::iterator inFace = pitEntry.m_incoming.find (incomingFace);
   CcnxPitEntryOutgoingFaceContainer::type::iterator outFace = pitEntry.m_outgoing.find (incomingFace);

   if (outFace != pitEntry.m_outgoing.end ())
     {
       // NS_ASSERT_MSG (outFace != pitEntry.m_outgoing.end (),
       //                "Outgoing entry should exist");

       return;
     }

   outFace->m_face->LeakBucketByOnePacket ();
   m_pit->modify (m_pit->iterator_to (pitEntry),
                  ll::bind (&CcnxPitEntry::SetWaitingInVain, ll::_1, outFace));

   // m_droppedInterestsTrace (header, DROP_CONGESTION, m_node->GetObject<Ccnx> (), incomingFace);

   // If NACK is NACK_GIVEUP_PIT, then neighbor gave up trying to and removed it's PIT entry.
   // So, if we had an incoming entry to this neighbor, then we can remove it now

   if (header->GetNack () == CcnxInterestHeader::NACK_GIVEUP_PIT)
     {
       m_pit->modify (m_pit->iterator_to (pitEntry),
                      ll::bind (&CcnxPitEntry::RemoveIncoming, ll::_1, incomingFace));
     }

   m_fib->modify(m_fib->iterator_to (pitEntry.m_fibEntry),
                 ll::bind (&CcnxFibEntry::UpdateStatus,
                           ll::_1, incomingFace, CcnxFibFaceMetric::NDN_FIB_YELLOW));

   if (!pitEntry.AreAllOutgoingInVain ())
     {
       // suppress
       // Don't do anything, we are still expecting data from some other face

       return;
     }

   NS_ASSERT_MSG (m_forwardingStrategy != 0, "Need a forwarding protocol object to process packets");

   Ptr<Packet> nonNackInterest = Create<Packet> ();
   header->SetNack (CcnxInterestHeader::NORMAL_INTEREST);
   nonNackInterest->AddHeader (*header);

   bool propagated = m_forwardingStrategy->
     PropagateInterest (pitEntry, incomingFace, header, nonNackInterest);

   // ForwardingStrategy will try its best to forward packet to at least one interface.
   // If no interests was propagated, then there is not other option for forwarding or
   // ForwardingStrategy failed to find it.
   if (!propagated && pitEntry.AreAllOutgoingInVain ())
     GiveUpInterest (pitEntry, header);
 }

 // Processing Interests
 //
 // !!! Key point.
 // !!! All interests should be answerred!!! Either later with data, immediately with data, or immediately with NACK
 void CcnxL3Protocol::OnInterest (const Ptr<CcnxFace> &incomingFace,
                                  Ptr<CcnxInterestHeader> &header,
                                  const Ptr<const Packet> &packet)
 {
   NS_LOG_FUNCTION (incomingFace << header << packet);
   // m_receivedInterestsTrace (header, m_node->GetObject<Ccnx> (), incomingFace);

   // Lookup of Pit (and associated Fib) entry for this Interest
   tuple<const CcnxPitEntry&,bool,bool> ret = m_pit->Lookup (*header);
   CcnxPitEntry const& pitEntry = ret.get<0> ();
   // bool isNew = ret.get<1> ();
   bool isDuplicated = ret.get<2> ();

   if (isDuplicated)
     {
       /**
        * This condition will handle "routing" loops and also recently satisfied interests.
        * Every time interest is satisfied, PIT entry (with empty incoming and outgoing faces)
        * is kept for another small chunk of time.
        */

       // //Trace duplicate interest
       // m_droppedInterestsTrace (header, NDN_DUPLICATE_INTEREST, m_node->GetObject<Ccnx> (), incomingFace);

       header->SetNack (CcnxInterestHeader::NACK_LOOP);
       Ptr<Packet> packet = Create<Packet> ();
       packet->AddHeader (*header);

       incomingFace->Send (packet);

       // //Trace duplicate interest
       // m_droppedInterestsTrace (header, NDN_DUPLICATE_INTEREST, m_node->GetObject<Ccnx> (), incomingFace);
       return;
     }

   Ptr<Packet> contentObject;
   Ptr<const CcnxContentObjectHeader> contentObjectHeader; // unused for now
   tie (contentObject, contentObjectHeader) = m_contentStore->Lookup (header);
   if (contentObject != 0)
     {
       NS_ASSERT (contentObjectHeader != 0);

       NS_LOG_LOGIC("Found in cache");

       // TransmittedDataTrace (contentObject, CACHED,
       //                       m_node->GetObject<Ccnx> (), incomingFace);
       incomingFace->Send (contentObject);

       // Set pruning timout on PIT entry (instead of deleting the record)
       m_pit->modify (m_pit->iterator_to (pitEntry),
                      bind (&CcnxPitEntry::SetExpireTime, ll::_1,
                            Simulator::Now () + m_pit->GetPitEntryPruningTimeout ()));
       return;
     }

   // \todo Detect retransmissions. Not yet sure how...

   // Data is not in cache
   CcnxPitEntryIncomingFaceContainer::type::iterator inFace = pitEntry.m_incoming.find (incomingFace);
   CcnxPitEntryOutgoingFaceContainer::type::iterator outFace = pitEntry.m_outgoing.find (incomingFace);

   if (inFace != pitEntry.m_incoming.end ())
     {
       // CcnxPitEntryIncomingFace.m_arrivalTime keeps track arrival time of the first packet... why?

       // this is almost definitely a retransmission. But should we trust the user on that?
     }
   else
     {
       m_pit->modify (m_pit->iterator_to (pitEntry),
                      ll::var(inFace) = ll::bind (&CcnxPitEntry::AddIncoming, ll::_1, incomingFace));
     }

   if (outFace != pitEntry.m_outgoing.end ())
     {
       // got a non-duplicate interest from the face we have sent interest to
       // Probably, there is no point in waiting data from that face... Not sure yet

       // If we're expecting data from the interface we got the interest from ("producer" asks us for "his own" data)
       // Mark interface YELLOW, but keep a small hope that data will come eventually.

       // ?? not sure if we need to do that ?? ...

       m_fib->modify(m_fib->iterator_to (pitEntry.m_fibEntry),
                     ll::bind (&CcnxFibEntry::UpdateStatus,
                               ll::_1, incomingFace, CcnxFibFaceMetric::NDN_FIB_YELLOW));
     }

   if (pitEntry.AreTherePromisingOutgoingFacesExcept (incomingFace))
     { // Suppress this interest if we're still expecting data from some other face

       // We are already expecting data later in future. Suppress the interest
       // m_droppedInterestsTrace (header, NDN_SUPPRESSED_INTEREST, m_node->GetObject<Ccnx> (), incomingFace);
       return;
     }

   /////////////////////////////////////////////////////////////////////
   // Propagate
   /////////////////////////////////////////////////////////////////////

   NS_ASSERT_MSG (m_forwardingStrategy != 0, "Need a forwarding protocol object to process packets");

   bool propagated = m_forwardingStrategy->
     PropagateInterest (pitEntry, incomingFace, header, packet);

   // ForwardingStrategy will try its best to forward packet to at least one interface.
   // If no interests was propagated, then there is not other option for forwarding or
   // ForwardingStrategy failed to find it.
   if (!propagated && pitEntry.AreAllOutgoingInVain ())
     GiveUpInterest (pitEntry, header);
 }

 void
 CcnxL3Protocol::GiveUpInterest (const CcnxPitEntry &pitEntry,
                                 Ptr<CcnxInterestHeader> header)
 {
   Ptr<Packet> packet = Create<Packet> ();
   header->SetNack (CcnxInterestHeader::NACK_GIVEUP_PIT);
   packet->AddHeader (*header);

   BOOST_FOREACH (const CcnxPitEntryIncomingFace &incoming, pitEntry.m_incoming)
     {
       incoming.m_face->Send (packet->Copy ());

       // m_droppedInterestsTrace (header, DROP_CONGESTION,
       //                          m_node->GetObject<Ccnx> (), incomingFace);
     }
   // All incoming interests cannot be satisfied. Remove them
   m_pit->modify (m_pit->iterator_to (pitEntry),
                  ll::bind (&CcnxPitEntry::ClearIncoming, ll::_1));

   // Set pruning timout on PIT entry (instead of deleting the record)
   m_pit->modify (m_pit->iterator_to (pitEntry),
                  ll::bind (&CcnxPitEntry::SetExpireTime, ll::_1,
                            Simulator::Now () + m_pit->GetPitEntryPruningTimeout ()));
 }


 // Processing ContentObjects
 void
 CcnxL3Protocol::OnData (const Ptr<CcnxFace> &incomingFace,
                         Ptr<CcnxContentObjectHeader> &header,
                         Ptr<Packet> &payload,
                         const Ptr<const Packet> &packet)
 {

   NS_LOG_FUNCTION (incomingFace << header << payload << packet);
   // m_receivedDataTrace (header, payload, m_node->GetObject<Ccnx> ()/*this*/, incomingFace);

   // 1. Lookup PIT entry
   try
     {
       const CcnxPitEntry &pitEntry = m_pit->Lookup (*header);

       // Note that with MultiIndex we need to modify entries indirectly

       CcnxPitEntryOutgoingFaceContainer::type::iterator out = pitEntry.m_outgoing.find (incomingFace);

       // If we have sent interest for this data via this face, then update stats.
       if (out != pitEntry.m_outgoing.end ())
         {
           m_fib->modify (m_fib->iterator_to (pitEntry.m_fibEntry),
                          ll::bind (&CcnxFibEntry::UpdateFaceRtt,
                                    ll::_1,
                                    incomingFace,
                                    Simulator::Now () - out->m_sendTime));
         }
       else
         {
           // Unsolicited data, but we're interested in it... should we get it?
           // Potential hole for attacks

           NS_LOG_ERROR ("Node "<< m_node->GetId() <<
                        ". PIT entry for "<< header->GetName ()<<" is valid, "
                         "but outgoing entry for interface "<< boost::cref(*incomingFace) <<" doesn't exist\n");

           // ignore unsolicited data
           return;
         }

       // Update metric status for the incoming interface in the corresponding FIB entry
       m_fib->modify (m_fib->iterator_to (pitEntry.m_fibEntry),
                      ll::bind (&CcnxFibEntry::UpdateStatus, ll::_1,
                                incomingFace, CcnxFibFaceMetric::NDN_FIB_GREEN));

       // Add or update entry in the content store
       m_contentStore->Add (header, payload);

       //satisfy all pending incoming Interests
       BOOST_FOREACH (const CcnxPitEntryIncomingFace &incoming, pitEntry.m_incoming)
         {
           if (incoming.m_face != incomingFace)
             incoming.m_face->Send (packet->Copy ());

           // successfull forwarded data trace
         }
       // All incoming interests are satisfied. Remove them
       m_pit->modify (m_pit->iterator_to (pitEntry),
                      ll::bind (&CcnxPitEntry::ClearIncoming, ll::_1));

       // Set pruning timout on PIT entry (instead of deleting the record)
       m_pit->modify (m_pit->iterator_to (pitEntry),
                      ll::bind (&CcnxPitEntry::SetExpireTime, ll::_1,
                                   Simulator::Now () + m_pit->GetPitEntryPruningTimeout ()));
     }
   catch (CcnxPitEntryNotFound)
     {
       // 2. Drop data packet if PIT entry is not found
       //    (unsolicited data packets should not "poison" content store)

       //drop dulicated or not requested data packet
       // m_droppedDataTrace (header, payload, NDN_UNSOLICITED_DATA, m_node->GetObject<Ccnx> (), incomingFace);
       return; // do not process unsoliced data packets
     }
 }

 void
 CcnxL3Protocol::SetBucketLeakInterval (Time interval)
 {
   m_bucketLeakInterval = interval;

   if (m_bucketLeakEvent.IsRunning ())
     m_bucketLeakEvent.Cancel ();

   m_bucketLeakEvent = Simulator::Schedule (m_bucketLeakInterval,
                                            &CcnxL3Protocol::LeakBuckets, this);
 }

 Time
 CcnxL3Protocol::GetBucketLeakInterval () const
 {
   return m_bucketLeakInterval;
 }

 void
 CcnxL3Protocol::LeakBuckets ()
 {
   NS_LOG_FUNCTION (this);
   NS_LOG_ERROR ("Bucket Interval: " << m_bucketLeakInterval.ToDouble(Time::S));

   BOOST_FOREACH (const Ptr<CcnxFace> &face, m_faces)
     {
       face->LeakBucket (m_bucketLeakInterval);
     }

   m_bucketLeakEvent = Simulator::Schedule (m_bucketLeakInterval,
                                            &CcnxL3Protocol::LeakBuckets,
                                            this);
 }

 } //namespace ns3
	/* -- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -- */
	/*
	* Copyright (c) 2011 University of California, Los Angeles
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation;
	*
	* This program 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 this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*
	* Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
	* Ilya Moiseenko <iliamo@cs.ucla.edu>
	*/

	#include "ccnx-l3-protocol.h"

	#include "ns3/packet.h"
	#include "ns3/node.h"
	#include "ns3/log.h"
	#include "ns3/callback.h"
	#include "ns3/uinteger.h"
	#include "ns3/trace-source-accessor.h"
	#include "ns3/object-vector.h"
	#include "ns3/boolean.h"

	#include "ns3/ccnx-header-helper.h"

	#include "ccnx-face.h"
	#include "ccnx-forwarding-strategy.h"
	#include "ccnx-interest-header.h"
	#include "ccnx-content-object-header.h"

	#include "ccnx-net-device-face.h"

	#include <boost/foreach.hpp>
	#include <boost/lambda/lambda.hpp>
	#include <boost/lambda/bind.hpp>

	using namespace boost::tuples;
	namespace ll = boost::lambda;

	NS_LOG_COMPONENT_DEFINE ("CcnxL3Protocol");

	namespace ns3 {

	const uint16_t CcnxL3Protocol::ETHERNET_FRAME_TYPE = 0x7777;

	NS_OBJECT_ENSURE_REGISTERED (CcnxL3Protocol);

	TypeId
	CcnxL3Protocol::GetTypeId (void)
	{
	static TypeId tid = TypeId ("ns3::CcnxL3Protocol")
	.SetParent<Ccnx> ()
	.SetGroupName ("Ccnx")
	.AddConstructor<CcnxL3Protocol> ()
	.AddAttribute ("BucketLeakInterval",
	"Interval to leak buckets",
	StringValue ("10ms"),
	MakeTimeAccessor (&CcnxL3Protocol::GetBucketLeakInterval,
	&CcnxL3Protocol::SetBucketLeakInterval),
	MakeTimeChecker ())
	;
	return tid;
	}

	CcnxL3Protocol::CcnxL3Protocol()
	: m_faceCounter (0)
	{
	NS_LOG_FUNCTION (this);

	m_pit = CreateObject<CcnxPit> ();
	m_contentStore = CreateObject<CcnxContentStore> ();
	}

	CcnxL3Protocol::~CcnxL3Protocol ()
	{
	NS_LOG_FUNCTION (this);
	}

	void
	CcnxL3Protocol::SetNode (Ptr<Node> node)
	{
	m_node = node;
	m_fib = m_node->GetObject<CcnxFib> ();
	NS_ASSERT_MSG (m_fib != 0, "FIB should be created and aggregated to a node before calling Ccnx::SetNode");

	m_pit->SetFib (m_fib);
	}

	/*
	* This method is called by AddAgregate and completes the aggregation
	* by setting the node in the ccnx stack
	*/
	void
	CcnxL3Protocol::NotifyNewAggregate ()
	{
	if (m_node == 0)
	{
	Ptr<Node>node = this->GetObject<Node>();
	// verify that it's a valid node and that
	// the node has not been set before
	if (node != 0)
	{
	this->SetNode (node);
	}
	}
	Object::NotifyNewAggregate ();
	}

	void
	CcnxL3Protocol::DoDispose (void)
	{
	NS_LOG_FUNCTION (this);

	if (m_bucketLeakEvent.IsRunning ())
	m_bucketLeakEvent.Cancel ();

	for (CcnxFaceList::iterator i = m_faces.begin (); i != m_faces.end (); ++i)
	{
	*i = 0;
	}
	m_faces.clear ();
	m_node = 0;

	// Force delete on objects
	m_forwardingStrategy = 0; // there is a reference to PIT stored in here
	m_pit = 0;
	m_contentStore = 0;
	m_fib = 0;

	// m_forwardingStrategy = 0;
	Object::DoDispose ();
	}

	void
	CcnxL3Protocol::SetForwardingStrategy (Ptr<CcnxForwardingStrategy> forwardingStrategy)
	{
	NS_LOG_FUNCTION (this);
	m_forwardingStrategy = forwardingStrategy;
	m_forwardingStrategy->SetPit (m_pit);
	}

	Ptr<CcnxForwardingStrategy>
	CcnxL3Protocol::GetForwardingStrategy (void) const
	{
	return m_forwardingStrategy;
	}

	uint32_t
	CcnxL3Protocol::AddFace (const Ptr<CcnxFace> &face)
	{
	NS_LOG_FUNCTION (this << &face);

	face->SetId (m_faceCounter); // sets a unique ID of the face. This ID serves only informational purposes

	// ask face to register in lower-layer stack
	face->RegisterProtocolHandler (MakeCallback (&CcnxL3Protocol::Receive, this));

	m_faces.push_back (face);
	m_faceCounter++;
	return face->GetId ();
	}

	void
	CcnxL3Protocol::RemoveFace (Ptr<CcnxFace> face)
	{
	// ask face to register in lower-layer stack
	face->RegisterProtocolHandler (MakeNullCallback<void,const Ptr<CcnxFace>&,const Ptr<const Packet>&> ());

	// just to be on a safe side. Do the process in two steps
	std::list<CcnxPitEntryContainer::type::iterator> entriesToRemoves;
	BOOST_FOREACH (const CcnxPitEntry &pitEntry, *m_pit)
	{
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::bind (&CcnxPitEntry::RemoveAllReferencesToFace, ll::_1, face));

	// If this face is the only for the associated FIB entry, then FIB entry will be removed soon.
	// Thus, we have to remove the whole PIT entry
	if (pitEntry.m_fibEntry.m_faces.size () == 1 &&
	pitEntry.m_fibEntry.m_faces.begin ()->m_face == face)
	{
	entriesToRemoves.push_back (m_pit->iterator_to (pitEntry));
	}
	}
	BOOST_FOREACH (CcnxPitEntryContainer::type::iterator entry, entriesToRemoves)
	{
	m_pit->erase (entry);
	}

	CcnxFaceList::iterator face_it = find (m_faces.begin(), m_faces.end(), face);
	NS_ASSERT_MSG (face_it != m_faces.end (), "Attempt to remove face that doesn't exist");
	m_faces.erase (face_it);
	}

	Ptr<CcnxFace>
	CcnxL3Protocol::GetFace (uint32_t index) const
	{
	BOOST_FOREACH (const Ptr<CcnxFace> &face, m_faces) // this function is not supposed to be called often, so linear search is fine
	{
	if (face->GetId () == index)
	return face;
	}
	return 0;
	}

	Ptr<CcnxFace>
	CcnxL3Protocol::GetFaceByNetDevice (Ptr<NetDevice> netDevice) const
	{
	BOOST_FOREACH (const Ptr<CcnxFace> &face, m_faces) // this function is not supposed to be called often, so linear search is fine
	{
	Ptr<CcnxNetDeviceFace> netDeviceFace = DynamicCast<CcnxNetDeviceFace> (face);
	if (netDeviceFace == 0) continue;

	if (netDeviceFace->GetNetDevice () == netDevice)
	return face;
	}
	return 0;
	}

	uint32_t
	CcnxL3Protocol::GetNFaces (void) const
	{
	return m_faces.size ();
	}

	// Callback from lower layer
	void
	CcnxL3Protocol::Receive (const Ptr<CcnxFace> &face, const Ptr<const Packet> &p)
	{
	if (!face->IsUp ())
	{
	NS_LOG_LOGIC ("Dropping received packet -- interface is down");
	// m_dropTrace (p, INTERFACE_DOWN, m_node->GetObject<Ccnx> ()/this/, face);
	return;
	}
	NS_LOG_LOGIC ("Packet from face " << *face << " received on node " << m_node->GetId ());

	Ptr<Packet> packet = p->Copy (); // give upper layers a rw copy of the packet
	try
	{
	CcnxHeaderHelper::Type type = CcnxHeaderHelper::GetCcnxHeaderType (p);
	switch (type)
	{
	case CcnxHeaderHelper::INTEREST:
	{
	Ptr<CcnxInterestHeader> header = Create<CcnxInterestHeader> ();

	// Deserialization. Exception may be thrown
	packet->RemoveHeader (*header);
	NS_ASSERT_MSG (packet->GetSize () == 0, "Payload of Interests should be zero");

	if (header->GetNack () > 0)
	OnNack (face, header, p/original packet/);
	else
	OnInterest (face, header, p/original packet/);
	break;
	}
	case CcnxHeaderHelper::CONTENT_OBJECT:
	{
	Ptr<CcnxContentObjectHeader> header = Create<CcnxContentObjectHeader> ();

	static CcnxContentObjectTail contentObjectTrailer; //there is no data in this object

	// Deserialization. Exception may be thrown
	packet->RemoveHeader (*header);
	packet->RemoveTrailer (contentObjectTrailer);

	OnData (face, header, packet/payload/, p/original packet/);
	break;
	}
	}

	// exception will be thrown if packet is not recognized
	}
	catch (CcnxUnknownHeaderException)
	{
	NS_ASSERT_MSG (false, "Unknown CCNx header. Should not happen");
	}
	}

	void
	CcnxL3Protocol::OnNack (const Ptr<CcnxFace> &incomingFace,
	Ptr<CcnxInterestHeader> &header,
	const Ptr<const Packet> &packet)
	{
	NS_LOG_FUNCTION (incomingFace << header << packet);

	tuple<const CcnxPitEntry&,bool,bool> ret = m_pit->Lookup (*header);
	CcnxPitEntry const& pitEntry = ret.get<0> ();
	bool isNew = ret.get<1> ();
	//bool isDuplicated = ret.get<2> ();

	// NS_ASSERT_MSG (isDuplicated,
	// "NACK should be a duplicated interest");
	if (isNew /\|\| !isDuplicated/) // potential flow
	{
	// somebody is doing something bad
	NS_ASSERT (false); // temporary assert
	return;
	}

	// CcnxPitEntryIncomingFaceContainer::type::iterator inFace = pitEntry.m_incoming.find (incomingFace);
	CcnxPitEntryOutgoingFaceContainer::type::iterator outFace = pitEntry.m_outgoing.find (incomingFace);

	if (outFace != pitEntry.m_outgoing.end ())
	{
	// NS_ASSERT_MSG (outFace != pitEntry.m_outgoing.end (),
	// "Outgoing entry should exist");

	return;
	}

	outFace->m_face->LeakBucketByOnePacket ();
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::bind (&CcnxPitEntry::SetWaitingInVain, ll::_1, outFace));

	// m_droppedInterestsTrace (header, DROP_CONGESTION, m_node->GetObject<Ccnx> (), incomingFace);

	// If NACK is NACK_GIVEUP_PIT, then neighbor gave up trying to and removed it's PIT entry.
	// So, if we had an incoming entry to this neighbor, then we can remove it now

	if (header->GetNack () == CcnxInterestHeader::NACK_GIVEUP_PIT)
	{
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::bind (&CcnxPitEntry::RemoveIncoming, ll::_1, incomingFace));
	}

	m_fib->modify(m_fib->iterator_to (pitEntry.m_fibEntry),
	ll::bind (&CcnxFibEntry::UpdateStatus,
	ll::_1, incomingFace, CcnxFibFaceMetric::NDN_FIB_YELLOW));

	if (!pitEntry.AreAllOutgoingInVain ())
	{
	// suppress
	// Don't do anything, we are still expecting data from some other face

	return;
	}

	NS_ASSERT_MSG (m_forwardingStrategy != 0, "Need a forwarding protocol object to process packets");

	Ptr<Packet> nonNackInterest = Create<Packet> ();
	header->SetNack (CcnxInterestHeader::NORMAL_INTEREST);
	nonNackInterest->AddHeader (*header);

	bool propagated = m_forwardingStrategy->
	PropagateInterest (pitEntry, incomingFace, header, nonNackInterest);

	// ForwardingStrategy will try its best to forward packet to at least one interface.
	// If no interests was propagated, then there is not other option for forwarding or
	// ForwardingStrategy failed to find it.
	if (!propagated && pitEntry.AreAllOutgoingInVain ())
	GiveUpInterest (pitEntry, header);
	}

	// Processing Interests
	//
	// !!! Key point.
	// !!! All interests should be answerred!!! Either later with data, immediately with data, or immediately with NACK
	void CcnxL3Protocol::OnInterest (const Ptr<CcnxFace> &incomingFace,
	Ptr<CcnxInterestHeader> &header,
	const Ptr<const Packet> &packet)
	{
	NS_LOG_FUNCTION (incomingFace << header << packet);
	// m_receivedInterestsTrace (header, m_node->GetObject<Ccnx> (), incomingFace);

	// Lookup of Pit (and associated Fib) entry for this Interest
	tuple<const CcnxPitEntry&,bool,bool> ret = m_pit->Lookup (*header);
	CcnxPitEntry const& pitEntry = ret.get<0> ();
	// bool isNew = ret.get<1> ();
	bool isDuplicated = ret.get<2> ();

	if (isDuplicated)
	{
	/**
	* This condition will handle "routing" loops and also recently satisfied interests.
	* Every time interest is satisfied, PIT entry (with empty incoming and outgoing faces)
	* is kept for another small chunk of time.
	*/

	// //Trace duplicate interest
	// m_droppedInterestsTrace (header, NDN_DUPLICATE_INTEREST, m_node->GetObject<Ccnx> (), incomingFace);

	header->SetNack (CcnxInterestHeader::NACK_LOOP);
	Ptr<Packet> packet = Create<Packet> ();
	packet->AddHeader (*header);

	incomingFace->Send (packet);

	// //Trace duplicate interest
	// m_droppedInterestsTrace (header, NDN_DUPLICATE_INTEREST, m_node->GetObject<Ccnx> (), incomingFace);
	return;
	}

	Ptr<Packet> contentObject;
	Ptr<const CcnxContentObjectHeader> contentObjectHeader; // unused for now
	tie (contentObject, contentObjectHeader) = m_contentStore->Lookup (header);
	if (contentObject != 0)
	{
	NS_ASSERT (contentObjectHeader != 0);

	NS_LOG_LOGIC("Found in cache");

	// TransmittedDataTrace (contentObject, CACHED,
	// m_node->GetObject<Ccnx> (), incomingFace);
	incomingFace->Send (contentObject);

	// Set pruning timout on PIT entry (instead of deleting the record)
	m_pit->modify (m_pit->iterator_to (pitEntry),
	bind (&CcnxPitEntry::SetExpireTime, ll::_1,
	Simulator::Now () + m_pit->GetPitEntryPruningTimeout ()));
	return;
	}

	// \todo Detect retransmissions. Not yet sure how...

	// Data is not in cache
	CcnxPitEntryIncomingFaceContainer::type::iterator inFace = pitEntry.m_incoming.find (incomingFace);
	CcnxPitEntryOutgoingFaceContainer::type::iterator outFace = pitEntry.m_outgoing.find (incomingFace);

	if (inFace != pitEntry.m_incoming.end ())
	{
	// CcnxPitEntryIncomingFace.m_arrivalTime keeps track arrival time of the first packet... why?

	// this is almost definitely a retransmission. But should we trust the user on that?
	}
	else
	{
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::var(inFace) = ll::bind (&CcnxPitEntry::AddIncoming, ll::_1, incomingFace));
	}

	if (outFace != pitEntry.m_outgoing.end ())
	{
	// got a non-duplicate interest from the face we have sent interest to
	// Probably, there is no point in waiting data from that face... Not sure yet

	// If we're expecting data from the interface we got the interest from ("producer" asks us for "his own" data)
	// Mark interface YELLOW, but keep a small hope that data will come eventually.

	// ?? not sure if we need to do that ?? ...

	m_fib->modify(m_fib->iterator_to (pitEntry.m_fibEntry),
	ll::bind (&CcnxFibEntry::UpdateStatus,
	ll::_1, incomingFace, CcnxFibFaceMetric::NDN_FIB_YELLOW));
	}

	if (pitEntry.AreTherePromisingOutgoingFacesExcept (incomingFace))
	{ // Suppress this interest if we're still expecting data from some other face

	// We are already expecting data later in future. Suppress the interest
	// m_droppedInterestsTrace (header, NDN_SUPPRESSED_INTEREST, m_node->GetObject<Ccnx> (), incomingFace);
	return;
	}

	/////////////////////////////////////////////////////////////////////
	// Propagate
	/////////////////////////////////////////////////////////////////////

	NS_ASSERT_MSG (m_forwardingStrategy != 0, "Need a forwarding protocol object to process packets");

	bool propagated = m_forwardingStrategy->
	PropagateInterest (pitEntry, incomingFace, header, packet);

	// ForwardingStrategy will try its best to forward packet to at least one interface.
	// If no interests was propagated, then there is not other option for forwarding or
	// ForwardingStrategy failed to find it.
	if (!propagated && pitEntry.AreAllOutgoingInVain ())
	GiveUpInterest (pitEntry, header);
	}

	void
	CcnxL3Protocol::GiveUpInterest (const CcnxPitEntry &pitEntry,
	Ptr<CcnxInterestHeader> header)
	{
	Ptr<Packet> packet = Create<Packet> ();
	header->SetNack (CcnxInterestHeader::NACK_GIVEUP_PIT);
	packet->AddHeader (*header);

	BOOST_FOREACH (const CcnxPitEntryIncomingFace &incoming, pitEntry.m_incoming)
	{
	incoming.m_face->Send (packet->Copy ());

	// m_droppedInterestsTrace (header, DROP_CONGESTION,
	// m_node->GetObject<Ccnx> (), incomingFace);
	}
	// All incoming interests cannot be satisfied. Remove them
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::bind (&CcnxPitEntry::ClearIncoming, ll::_1));

	// Set pruning timout on PIT entry (instead of deleting the record)
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::bind (&CcnxPitEntry::SetExpireTime, ll::_1,
	Simulator::Now () + m_pit->GetPitEntryPruningTimeout ()));
	}


	// Processing ContentObjects
	void
	CcnxL3Protocol::OnData (const Ptr<CcnxFace> &incomingFace,
	Ptr<CcnxContentObjectHeader> &header,
	Ptr<Packet> &payload,
	const Ptr<const Packet> &packet)
	{

	NS_LOG_FUNCTION (incomingFace << header << payload << packet);
	// m_receivedDataTrace (header, payload, m_node->GetObject<Ccnx> ()/this/, incomingFace);

	// 1. Lookup PIT entry
	try
	{
	const CcnxPitEntry &pitEntry = m_pit->Lookup (*header);

	// Note that with MultiIndex we need to modify entries indirectly

	CcnxPitEntryOutgoingFaceContainer::type::iterator out = pitEntry.m_outgoing.find (incomingFace);

	// If we have sent interest for this data via this face, then update stats.
	if (out != pitEntry.m_outgoing.end ())
	{
	m_fib->modify (m_fib->iterator_to (pitEntry.m_fibEntry),
	ll::bind (&CcnxFibEntry::UpdateFaceRtt,
	ll::_1,
	incomingFace,
	Simulator::Now () - out->m_sendTime));
	}
	else
	{
	// Unsolicited data, but we're interested in it... should we get it?
	// Potential hole for attacks

	NS_LOG_ERROR ("Node "<< m_node->GetId() <<
	". PIT entry for "<< header->GetName ()<<" is valid, "
	"but outgoing entry for interface "<< boost::cref(*incomingFace) <<" doesn't exist\n");

	// ignore unsolicited data
	return;
	}

	// Update metric status for the incoming interface in the corresponding FIB entry
	m_fib->modify (m_fib->iterator_to (pitEntry.m_fibEntry),
	ll::bind (&CcnxFibEntry::UpdateStatus, ll::_1,
	incomingFace, CcnxFibFaceMetric::NDN_FIB_GREEN));

	// Add or update entry in the content store
	m_contentStore->Add (header, payload);

	//satisfy all pending incoming Interests
	BOOST_FOREACH (const CcnxPitEntryIncomingFace &incoming, pitEntry.m_incoming)
	{
	if (incoming.m_face != incomingFace)
	incoming.m_face->Send (packet->Copy ());

	// successfull forwarded data trace
	}
	// All incoming interests are satisfied. Remove them
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::bind (&CcnxPitEntry::ClearIncoming, ll::_1));

	// Set pruning timout on PIT entry (instead of deleting the record)
	m_pit->modify (m_pit->iterator_to (pitEntry),
	ll::bind (&CcnxPitEntry::SetExpireTime, ll::_1,
	Simulator::Now () + m_pit->GetPitEntryPruningTimeout ()));
	}
	catch (CcnxPitEntryNotFound)
	{
	// 2. Drop data packet if PIT entry is not found
	// (unsolicited data packets should not "poison" content store)

	//drop dulicated or not requested data packet
	// m_droppedDataTrace (header, payload, NDN_UNSOLICITED_DATA, m_node->GetObject<Ccnx> (), incomingFace);
	return; // do not process unsoliced data packets
	}
	}

	void
	CcnxL3Protocol::SetBucketLeakInterval (Time interval)
	{
	m_bucketLeakInterval = interval;

	if (m_bucketLeakEvent.IsRunning ())
	m_bucketLeakEvent.Cancel ();

	m_bucketLeakEvent = Simulator::Schedule (m_bucketLeakInterval,
	&CcnxL3Protocol::LeakBuckets, this);
	}

	Time
	CcnxL3Protocol::GetBucketLeakInterval () const
	{
	return m_bucketLeakInterval;
	}

	void
	CcnxL3Protocol::LeakBuckets ()
	{
	NS_LOG_FUNCTION (this);
	NS_LOG_ERROR ("Bucket Interval: " << m_bucketLeakInterval.ToDouble(Time::S));

	BOOST_FOREACH (const Ptr<CcnxFace> &face, m_faces)
	{
	face->LeakBucket (m_bucketLeakInterval);
	}

	m_bucketLeakEvent = Simulator::Schedule (m_bucketLeakInterval,
	&CcnxL3Protocol::LeakBuckets,
	this);
	}

	} //namespace ns3