lte-enb-rrc.cc

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/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2011 Centre Tecnologic de Telecomunicacions de Catalunya (CTTC)
 *
 * 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
 *
 * Authors: Nicola Baldo <nbaldo@cttc.es>
 *          Marco Miozzo <mmiozzo@cttc.es>
 *          Manuel Requena <manuel.requena@cttc.es>
 */

#include "lte-enb-rrc.h"

#include <ns3/fatal-error.h>
#include <ns3/log.h>
#include <ns3/abort.h>

#include <ns3/pointer.h>
#include <ns3/object-map.h>
#include <ns3/object-factory.h>
#include <ns3/simulator.h>

#include <ns3/lte-radio-bearer-info.h>
#include <ns3/eps-bearer-tag.h>
#include <ns3/packet.h>

#include <ns3/lte-rlc.h>
#include <ns3/lte-rlc-tm.h>
#include <ns3/lte-rlc-um.h>
#include <ns3/lte-rlc-am.h>
#include <ns3/lte-pdcp.h>




NS_LOG_COMPONENT_DEFINE ("LteEnbRrc");


namespace ns3 {


// CMAC SAP forwarder

class EnbRrcMemberLteEnbCmacSapUser : public LteEnbCmacSapUser
{
public:
  EnbRrcMemberLteEnbCmacSapUser (LteEnbRrc* rrc);

  virtual uint16_t AllocateTemporaryCellRnti ();
  virtual void NotifyLcConfigResult (uint16_t rnti, uint8_t lcid, bool success);
  virtual void RrcConfigurationUpdateInd (UeConfig params);

private:
  LteEnbRrc* m_rrc;
};

EnbRrcMemberLteEnbCmacSapUser::EnbRrcMemberLteEnbCmacSapUser (LteEnbRrc* rrc)
  : m_rrc (rrc)
{
}

uint16_t
EnbRrcMemberLteEnbCmacSapUser::AllocateTemporaryCellRnti ()
{
  return m_rrc->DoAllocateTemporaryCellRnti ();
}

void
EnbRrcMemberLteEnbCmacSapUser::NotifyLcConfigResult (uint16_t rnti, uint8_t lcid, bool success)
{
  m_rrc->DoNotifyLcConfigResult (rnti, lcid, success);
}

void
EnbRrcMemberLteEnbCmacSapUser::RrcConfigurationUpdateInd (UeConfig params)
{
  m_rrc->DoRrcConfigurationUpdateInd (params);
}



// UeManager


static const std::string g_ueManagerStateName[UeManager::NUM_STATES] =
{
  "INITIAL_RANDOM_ACCESS",
  "CONNECTION_SETUP",
  "CONNECTION_REJECTED",
  "CONNECTED_NORMALLY",
  "CONNECTION_RECONFIGURATION",
  "CONNECTION_REESTABLISHMENT",
  "HANDOVER_PREPARATION",
  "HANDOVER_JOINING",
  "HANDOVER_PATH_SWITCH",
  "HANDOVER_LEAVING",
};

static const std::string & ToString (UeManager::State s)
{
  return g_ueManagerStateName[s];
}


NS_OBJECT_ENSURE_REGISTERED (UeManager);


UeManager::UeManager ()
{
  NS_FATAL_ERROR ("this constructor is not espected to be used");
}


UeManager::UeManager (Ptr<LteEnbRrc> rrc, uint16_t rnti, State s)
  : m_lastAllocatedDrbid (0),
    m_rnti (rnti),
    m_imsi (0),
    m_lastRrcTransactionIdentifier (0),
    m_rrc (rrc),
    m_state (s),
    m_pendingRrcConnectionReconfiguration (false),
    m_sourceX2apId (0),
    m_sourceCellId (0),
    m_needTransmissionModeConfiguration (false)
{ 
  NS_LOG_FUNCTION (this);
}

void
UeManager::DoInitialize ()
{
  NS_LOG_FUNCTION (this);
  m_drbPdcpSapUser = new LtePdcpSpecificLtePdcpSapUser<UeManager> (this);

  m_physicalConfigDedicated.haveAntennaInfoDedicated = true;
  m_physicalConfigDedicated.antennaInfo.transmissionMode = m_rrc->m_defaultTransmissionMode;
  m_physicalConfigDedicated.haveSoundingRsUlConfigDedicated = true;
  m_physicalConfigDedicated.soundingRsUlConfigDedicated.srsConfigIndex = m_rrc->GetNewSrsConfigurationIndex ();
  m_physicalConfigDedicated.soundingRsUlConfigDedicated.type = LteRrcSap::SoundingRsUlConfigDedicated::SETUP;
  m_physicalConfigDedicated.soundingRsUlConfigDedicated.srsBandwidth = 0;

  m_rrc->m_cmacSapProvider->AddUe (m_rnti);
  m_rrc->m_cphySapProvider->AddUe (m_rnti);

  // setup the eNB side of SRB0
  {
    uint8_t lcid = 0;

    Ptr<LteRlc> rlc = CreateObject<LteRlcTm> ()->GetObject<LteRlc> ();
    rlc->SetLteMacSapProvider (m_rrc->m_macSapProvider);
    rlc->SetRnti (m_rnti);
    rlc->SetLcId (lcid);

    m_srb0 = CreateObject<LteSignalingRadioBearerInfo> ();  
    m_srb0->m_rlc = rlc;
    m_srb0->m_srbIdentity = 0;
    // no need to store logicalChannelConfig as SRB0 is pre-configured

    LteEnbCmacSapProvider::LcInfo lcinfo;
    lcinfo.rnti = m_rnti;
    lcinfo.lcId = lcid;
    // leave the rest of lcinfo empty as CCCH (LCID 0) is pre-configured
    m_rrc->m_cmacSapProvider->AddLc (lcinfo, rlc->GetLteMacSapUser ());
    
  }

  // setup the eNB side of SRB1; the UE side will be set up upon RRC connection establishment
  {
    uint8_t lcid = 1;

    Ptr<LteRlc> rlc = CreateObject<LteRlcAm> ()->GetObject<LteRlc> ();
    rlc->SetLteMacSapProvider (m_rrc->m_macSapProvider);
    rlc->SetRnti (m_rnti);
    rlc->SetLcId (lcid);

    Ptr<LtePdcp> pdcp = CreateObject<LtePdcp> ();
    pdcp->SetRnti (m_rnti);
    pdcp->SetLcId (lcid);
    pdcp->SetLtePdcpSapUser (m_drbPdcpSapUser);
    pdcp->SetLteRlcSapProvider (rlc->GetLteRlcSapProvider ());
    rlc->SetLteRlcSapUser (pdcp->GetLteRlcSapUser ());

    m_srb1 = CreateObject<LteSignalingRadioBearerInfo> ();  
    m_srb1->m_rlc = rlc;
    m_srb1->m_pdcp = pdcp;
    m_srb1->m_srbIdentity = 1;
    m_srb1->m_logicalChannelConfig.priority = 0;
    m_srb1->m_logicalChannelConfig.prioritizedBitRateKbps = 100;
    m_srb1->m_logicalChannelConfig.bucketSizeDurationMs = 100;
    m_srb1->m_logicalChannelConfig.logicalChannelGroup = 0;
    
    LteEnbCmacSapProvider::LcInfo lcinfo;
    lcinfo.rnti = m_rnti;
    lcinfo.lcId = lcid;
    lcinfo.lcGroup = 0; // all SRBs always mapped to LCG 0
    lcinfo.qci = EpsBearer::GBR_CONV_VOICE; // not sure why the FF API requires a CQI even for SRBs...
    lcinfo.isGbr = true;
    lcinfo.mbrUl = 1e6;
    lcinfo.mbrDl = 1e6;
    lcinfo.gbrUl = 1e4;
    lcinfo.gbrDl = 1e4;
    m_rrc->m_cmacSapProvider->AddLc (lcinfo, rlc->GetLteMacSapUser ());
  }

  LteEnbRrcSapUser::SetupUeParameters ueParams;
  ueParams.srb0SapProvider = m_srb0->m_rlc->GetLteRlcSapProvider ();
  ueParams.srb1SapProvider = m_srb1->m_pdcp->GetLtePdcpSapProvider ();
  m_rrc->m_rrcSapUser->SetupUe (m_rnti, ueParams);

  // configure MAC (and scheduler)
  LteEnbCmacSapProvider::UeConfig req;
  req.m_rnti = m_rnti;
  req.m_transmissionMode = m_physicalConfigDedicated.antennaInfo.transmissionMode;
  m_rrc->m_cmacSapProvider->UeUpdateConfigurationReq (req);
  
  // configure PHY
  m_rrc->m_cphySapProvider->SetTransmissionMode (m_rnti, m_physicalConfigDedicated.antennaInfo.transmissionMode);
  m_rrc->m_cphySapProvider->SetSrsConfigurationIndex (m_rnti, m_physicalConfigDedicated.soundingRsUlConfigDedicated.srsConfigIndex);

  // schedule this UeManager instance to be deleted if the UE does not give any sign of life within a reasonable time
  Time maxConnectionDelay;
  switch (m_state)
    {
    case INITIAL_RANDOM_ACCESS:
      m_connectionTimeout = Simulator::Schedule (m_rrc->m_connectionTimeoutDuration, 
                                                 &LteEnbRrc::ConnectionTimeout, 
                                                 m_rrc, m_rnti);
      break;

    case HANDOVER_JOINING:
      m_handoverJoiningTimeout = Simulator::Schedule (m_rrc->m_handoverJoiningTimeoutDuration, 
                                                      &LteEnbRrc::HandoverJoiningTimeout,
                                                      m_rrc, m_rnti);
      break;      

    default:
      NS_FATAL_ERROR ("unexpected state " << ToString (m_state));
      break;
    }

}


UeManager::~UeManager (void)
{
}

void
UeManager::DoDispose ()
{
  delete m_drbPdcpSapUser;
  // delete eventual X2-U TEIDs
  for (std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it = m_drbMap.begin ();
       it != m_drbMap.end ();
       ++it)
    {
      m_rrc->m_x2uTeidInfoMap.erase (it->second->m_gtpTeid);
    }

}

TypeId UeManager::GetTypeId (void)
{
  static TypeId  tid = TypeId ("ns3::UeManager")
    .SetParent<Object> ()
    .AddConstructor<UeManager> ()
    .AddAttribute ("DataRadioBearerMap", "List of UE DataRadioBearerInfo by DRBID.",
                   ObjectMapValue (),
                   MakeObjectMapAccessor (&UeManager::m_drbMap),
                   MakeObjectMapChecker<LteDataRadioBearerInfo> ())
    .AddAttribute ("Srb0", "SignalingRadioBearerInfo for SRB0",
                   PointerValue (),
                   MakePointerAccessor (&UeManager::m_srb0),
                   MakePointerChecker<LteSignalingRadioBearerInfo> ())
    .AddAttribute ("Srb1", "SignalingRadioBearerInfo for SRB1",
                   PointerValue (),
                   MakePointerAccessor (&UeManager::m_srb1),
                   MakePointerChecker<LteSignalingRadioBearerInfo> ())
    .AddAttribute ("C-RNTI",
                   "Cell Radio Network Temporary Identifier",
                   TypeId::ATTR_GET, // read-only attribute
                   UintegerValue (0), // unused, read-only attribute
                   MakeUintegerAccessor (&UeManager::m_rnti),
                   MakeUintegerChecker<uint16_t> ())
    .AddTraceSource ("StateTransition",
                     "fired upon every UE state transition seen by the UeManager at the eNB RRC",
                     MakeTraceSourceAccessor (&UeManager::m_stateTransitionTrace))
  ;
  return tid;
}

void 
UeManager::SetSource (uint16_t sourceCellId, uint16_t sourceX2apId)
{
  m_sourceX2apId = sourceX2apId;
  m_sourceCellId = sourceCellId;
}

void 
UeManager::SetImsi (uint64_t imsi)
{
  m_imsi = imsi;
}

void
UeManager::SetupDataRadioBearer (EpsBearer bearer, uint8_t bearerId, uint32_t gtpTeid, Ipv4Address transportLayerAddress)
{
  NS_LOG_FUNCTION (this << (uint32_t) m_rnti);

  Ptr<LteDataRadioBearerInfo> drbInfo = CreateObject<LteDataRadioBearerInfo> ();
  uint8_t drbid = AddDataRadioBearerInfo (drbInfo);
  uint8_t lcid = Drbid2Lcid (drbid); 
  uint8_t bid = Drbid2Bid (drbid);  
  NS_ASSERT_MSG ( bearerId == 0 || bid == bearerId, "bearer ID mismatch (" << (uint32_t) bid << " != " << (uint32_t) bearerId << ", the assumption that ID are allocated in the same way by MME and RRC is not valid any more");
  drbInfo->m_epsBearerIdentity = bid;
  drbInfo->m_drbIdentity = drbid;
  drbInfo->m_logicalChannelIdentity = lcid;
  drbInfo->m_gtpTeid = gtpTeid;
  drbInfo->m_transportLayerAddress = transportLayerAddress;

  if (m_state == HANDOVER_JOINING)
    {
      // setup TEIDs for receiving data eventually forwarded over X2-U 
      LteEnbRrc::X2uTeidInfo x2uTeidInfo;
      x2uTeidInfo.rnti = m_rnti;
      x2uTeidInfo.drbid = drbid;
      std::pair<std::map<uint32_t, LteEnbRrc::X2uTeidInfo>::iterator, bool>
        ret = m_rrc->m_x2uTeidInfoMap.insert (std::pair<uint32_t, LteEnbRrc::X2uTeidInfo> (gtpTeid, x2uTeidInfo));
      NS_ASSERT_MSG (ret.second == true, "overwriting a pre-existing entry in m_x2uTeidInfoMap");
    }

  TypeId rlcTypeId = m_rrc->GetRlcType (bearer);

  ObjectFactory rlcObjectFactory;
  rlcObjectFactory.SetTypeId (rlcTypeId);
  Ptr<LteRlc> rlc = rlcObjectFactory.Create ()->GetObject<LteRlc> ();
  rlc->SetLteMacSapProvider (m_rrc->m_macSapProvider);
  rlc->SetRnti (m_rnti);

  drbInfo->m_rlc = rlc;

  rlc->SetLcId (lcid);

  // we need PDCP only for real RLC, i.e., RLC/UM or RLC/AM
  // if we are using RLC/SM we don't care of anything above RLC
  if (rlcTypeId != LteRlcSm::GetTypeId ())
    {
      Ptr<LtePdcp> pdcp = CreateObject<LtePdcp> ();
      pdcp->SetRnti (m_rnti);
      pdcp->SetLcId (lcid);
      pdcp->SetLtePdcpSapUser (m_drbPdcpSapUser);
      pdcp->SetLteRlcSapProvider (rlc->GetLteRlcSapProvider ());
      rlc->SetLteRlcSapUser (pdcp->GetLteRlcSapUser ());
      drbInfo->m_pdcp = pdcp;
    }
    
  LteEnbCmacSapProvider::LcInfo lcinfo;
  lcinfo.rnti = m_rnti;
  lcinfo.lcId = lcid;
  lcinfo.lcGroup = m_rrc->GetLogicalChannelGroup (bearer);
  lcinfo.qci = bearer.qci;
  lcinfo.isGbr = bearer.IsGbr ();
  lcinfo.mbrUl = bearer.gbrQosInfo.mbrUl;
  lcinfo.mbrDl = bearer.gbrQosInfo.mbrDl;
  lcinfo.gbrUl = bearer.gbrQosInfo.gbrUl;
  lcinfo.gbrDl = bearer.gbrQosInfo.gbrDl;
  m_rrc->m_cmacSapProvider->AddLc (lcinfo, rlc->GetLteMacSapUser ());
  
  if (rlcTypeId == LteRlcAm::GetTypeId ())
    {
      drbInfo->m_rlcConfig.choice =  LteRrcSap::RlcConfig::AM;
    }
  else
    {
      drbInfo->m_rlcConfig.choice =  LteRrcSap::RlcConfig::UM_BI_DIRECTIONAL;
    }

  drbInfo->m_logicalChannelIdentity = lcid;
  drbInfo->m_logicalChannelConfig.priority =  m_rrc->GetLogicalChannelPriority (bearer);
  drbInfo->m_logicalChannelConfig.logicalChannelGroup = m_rrc->GetLogicalChannelGroup (bearer);
  if (bearer.IsGbr ())
    {
      drbInfo->m_logicalChannelConfig.prioritizedBitRateKbps = bearer.gbrQosInfo.gbrUl;      
    }
  else
    {
      drbInfo->m_logicalChannelConfig.prioritizedBitRateKbps = 0;
    }
  drbInfo->m_logicalChannelConfig.bucketSizeDurationMs = 1000;

  ScheduleRrcConnectionReconfiguration ();
}

void
UeManager::RecordDataRadioBearersToBeStarted ()
{
  NS_LOG_FUNCTION (this << (uint32_t) m_rnti);
  for (std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it = m_drbMap.begin ();
       it != m_drbMap.end ();
       ++it)
    {
      m_drbsToBeStarted.push_back (it->first);
    }    
}

void
UeManager::StartDataRadioBearers ()
{
  NS_LOG_FUNCTION (this << (uint32_t) m_rnti);
  for (std::list <uint8_t>::iterator drbIdIt = m_drbsToBeStarted.begin ();
       drbIdIt != m_drbsToBeStarted.end ();
       ++drbIdIt)
    {
      std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator drbIt = m_drbMap.find (*drbIdIt);
      NS_ASSERT (drbIt != m_drbMap.end ());
      drbIt->second->m_rlc->Initialize ();
      if (drbIt->second->m_pdcp)
        {
          drbIt->second->m_pdcp->Initialize ();
        }
    }
  m_drbsToBeStarted.clear ();
}


void
UeManager::ReleaseDataRadioBearer (uint8_t drbid)
{
  NS_LOG_FUNCTION (this << (uint32_t) m_rnti << (uint32_t) drbid);
  uint8_t lcid = Drbid2Lcid (drbid);
  std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it = m_drbMap.find (drbid);
  NS_ASSERT_MSG (it != m_drbMap.end (), "request to remove radio bearer with unknown drbid " << drbid);

  // first delete eventual X2-U TEIDs
  m_rrc->m_x2uTeidInfoMap.erase (it->second->m_gtpTeid);

  m_drbMap.erase (it);
  m_rrc->m_cmacSapProvider->ReleaseLc (m_rnti, lcid);

  LteRrcSap::RadioResourceConfigDedicated rrcd;
  rrcd.havePhysicalConfigDedicated = false;
  rrcd.drbToReleaseList.push_back (drbid);
 
  LteRrcSap::RrcConnectionReconfiguration msg;
  msg.haveMeasConfig = false;
  msg.haveMobilityControlInfo = false;
 
  m_rrc->m_rrcSapUser->SendRrcConnectionReconfiguration (m_rnti, msg);
}


void 
UeManager::ScheduleRrcConnectionReconfiguration ()
{
  NS_LOG_FUNCTION (this);
  switch (m_state)
    {
    case INITIAL_RANDOM_ACCESS:
    case CONNECTION_SETUP:
    case CONNECTION_RECONFIGURATION:
    case CONNECTION_REESTABLISHMENT:
    case HANDOVER_PREPARATION:
    case HANDOVER_JOINING:
    case HANDOVER_LEAVING:
      // a previous reconfiguration still ongoing, we need to wait for it to be finished
      m_pendingRrcConnectionReconfiguration = true;
      break;

    case CONNECTED_NORMALLY:
      {
        m_pendingRrcConnectionReconfiguration = false;
        LteRrcSap::RrcConnectionReconfiguration msg = BuildRrcConnectionReconfiguration ();
        m_rrc->m_rrcSapUser->SendRrcConnectionReconfiguration (m_rnti, msg);
        RecordDataRadioBearersToBeStarted ();
        SwitchToState (CONNECTION_RECONFIGURATION);
      }
      break;

    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;
    }
}

void 
UeManager::PrepareHandover (uint16_t cellId)
{
  NS_LOG_FUNCTION (this << cellId);
  switch (m_state)
    {
    case CONNECTED_NORMALLY:
      {
        m_targetCellId = cellId;
        EpcX2SapProvider::HandoverRequestParams params;
        params.oldEnbUeX2apId = m_rnti;
        params.cause          = EpcX2SapProvider::HandoverDesirableForRadioReason;
        params.sourceCellId   = m_rrc->m_cellId;
        params.targetCellId   = cellId;
        params.mmeUeS1apId    = m_imsi;
        params.ueAggregateMaxBitRateDownlink = 200 * 1000;
        params.ueAggregateMaxBitRateUplink = 100 * 1000;
        params.bearers = GetErabList ();
  
        LteRrcSap::HandoverPreparationInfo hpi;
        hpi.asConfig.sourceUeIdentity = m_rnti;
        hpi.asConfig.sourceDlCarrierFreq = m_rrc->m_dlEarfcn;
        hpi.asConfig.sourceMeasConfig = m_rrc->m_ueMeasConfig;
        hpi.asConfig.sourceRadioResourceConfig = GetRadioResourceConfigForHandoverPreparationInfo ();
        hpi.asConfig.sourceMasterInformationBlock.dlBandwidth = m_rrc->m_dlBandwidth;
        hpi.asConfig.sourceMasterInformationBlock.systemFrameNumber = 0;
        hpi.asConfig.sourceSystemInformationBlockType1.cellAccessRelatedInfo.plmnIdentityInfo.plmnIdentity = m_rrc->m_sib1.cellAccessRelatedInfo.plmnIdentityInfo.plmnIdentity;
        hpi.asConfig.sourceSystemInformationBlockType1.cellAccessRelatedInfo.cellIdentity = m_rrc->m_cellId;
        hpi.asConfig.sourceSystemInformationBlockType1.cellAccessRelatedInfo.csgIndication = m_rrc->m_sib1.cellAccessRelatedInfo.csgIndication;
        hpi.asConfig.sourceSystemInformationBlockType1.cellAccessRelatedInfo.csgIdentity = m_rrc->m_sib1.cellAccessRelatedInfo.csgIdentity;
        LteEnbCmacSapProvider::RachConfig rc = m_rrc->m_cmacSapProvider->GetRachConfig ();
        hpi.asConfig.sourceSystemInformationBlockType2.radioResourceConfigCommon.rachConfigCommon.preambleInfo.numberOfRaPreambles = rc.numberOfRaPreambles;
        hpi.asConfig.sourceSystemInformationBlockType2.radioResourceConfigCommon.rachConfigCommon.raSupervisionInfo.preambleTransMax = rc.preambleTransMax;
        hpi.asConfig.sourceSystemInformationBlockType2.radioResourceConfigCommon.rachConfigCommon.raSupervisionInfo.raResponseWindowSize = rc.raResponseWindowSize;
        hpi.asConfig.sourceSystemInformationBlockType2.freqInfo.ulCarrierFreq = m_rrc->m_ulEarfcn;
        hpi.asConfig.sourceSystemInformationBlockType2.freqInfo.ulBandwidth = m_rrc->m_ulBandwidth;
        params.rrcContext = m_rrc->m_rrcSapUser->EncodeHandoverPreparationInformation (hpi);
  
        NS_LOG_LOGIC ("oldEnbUeX2apId = " << params.oldEnbUeX2apId);
        NS_LOG_LOGIC ("sourceCellId = " << params.sourceCellId);
        NS_LOG_LOGIC ("targetCellId = " << params.targetCellId);
        NS_LOG_LOGIC ("mmeUeS1apId = " << params.mmeUeS1apId);
        NS_LOG_LOGIC ("rrcContext   = " << params.rrcContext);
  
        m_rrc->m_x2SapProvider->SendHandoverRequest (params);
        SwitchToState (HANDOVER_PREPARATION);
      }
      break;      
      
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;
    }

}

void 
UeManager::RecvHandoverRequestAck (EpcX2SapUser::HandoverRequestAckParams params)
{
  NS_LOG_FUNCTION (this);
  
  NS_ASSERT_MSG (params.notAdmittedBearers.empty (), "not admission of some bearers upon handover is not supported");
  NS_ASSERT_MSG (params.admittedBearers.size () == m_drbMap.size (), "not enough bearers in admittedBearers");

  // note: the Handover command from the target eNB to the source eNB
  // is expected to be sent transparently to the UE; however, here we
  // decode the message and eventually reencode it. This way we can
  // support both a real RRC protocol implementation and an ideal one
  // without actual RRC protocol encoding. 

  Ptr<Packet> encodedHandoverCommand = params.rrcContext;
  LteRrcSap::RrcConnectionReconfiguration handoverCommand = m_rrc->m_rrcSapUser->DecodeHandoverCommand (encodedHandoverCommand);
  m_rrc->m_rrcSapUser->SendRrcConnectionReconfiguration (m_rnti, handoverCommand);
  SwitchToState (HANDOVER_LEAVING);
  m_handoverLeavingTimeout = Simulator::Schedule (m_rrc->m_handoverLeavingTimeoutDuration, 
                                                  &LteEnbRrc::HandoverLeavingTimeout, 
                                                  m_rrc, m_rnti);
  NS_ASSERT (handoverCommand.haveMobilityControlInfo);
  m_rrc->m_handoverStartTrace (m_imsi, m_rrc->m_cellId, m_rnti, handoverCommand.mobilityControlInfo.targetPhysCellId);

  EpcX2SapProvider::SnStatusTransferParams sst;
  sst.oldEnbUeX2apId = params.oldEnbUeX2apId;
  sst.newEnbUeX2apId = params.newEnbUeX2apId;
  sst.sourceCellId = params.sourceCellId;
  sst.targetCellId = params.targetCellId;
  for ( std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator drbIt = m_drbMap.begin ();
        drbIt != m_drbMap.end ();
        ++drbIt)
    {
      // SN status transfer is only for AM RLC
      if (0 != drbIt->second->m_rlc->GetObject<LteRlcAm> ())
        {
          LtePdcp::Status status = drbIt->second->m_pdcp->GetStatus ();
          EpcX2Sap::ErabsSubjectToStatusTransferItem i;          
          i.dlPdcpSn = status.txSn;
          i.ulPdcpSn = status.rxSn;
          sst.erabsSubjectToStatusTransferList.push_back (i);
        }
    }
  m_rrc->m_x2SapProvider->SendSnStatusTransfer (sst);
}


LteRrcSap::RadioResourceConfigDedicated
UeManager::GetRadioResourceConfigForHandoverPreparationInfo ()
{
  NS_LOG_FUNCTION (this);
  return BuildRadioResourceConfigDedicated ();
}

LteRrcSap::RrcConnectionReconfiguration 
UeManager::GetRrcConnectionReconfigurationForHandover ()
{
  NS_LOG_FUNCTION (this);
  return BuildRrcConnectionReconfiguration ();
}

void
UeManager::SendData (uint8_t bid, Ptr<Packet> p)
{
  NS_LOG_FUNCTION (this << p << (uint16_t) bid);
  switch (m_state)
    {
    case INITIAL_RANDOM_ACCESS:
    case CONNECTION_SETUP:
      NS_LOG_WARN ("not connected, discarding packet");
      return;
      break;      
      
    case CONNECTED_NORMALLY:      
    case CONNECTION_RECONFIGURATION:
    case CONNECTION_REESTABLISHMENT:
    case HANDOVER_PREPARATION:
    case HANDOVER_JOINING:
    case HANDOVER_PATH_SWITCH:
      {
        NS_LOG_LOGIC ("queueing data on PDCP for transmission over the air");
        LtePdcpSapProvider::TransmitPdcpSduParameters params;
        params.pdcpSdu = p;
        params.rnti = m_rnti;
        params.lcid = Bid2Lcid (bid);
        uint8_t drbid = Bid2Drbid (bid);
        LtePdcpSapProvider* pdcpSapProvider = GetDataRadioBearerInfo (drbid)->m_pdcp->GetLtePdcpSapProvider ();
        pdcpSapProvider->TransmitPdcpSdu (params);
      }
      break;
      
    case HANDOVER_LEAVING:
      {
        NS_LOG_LOGIC ("forwarding data to target eNB over X2-U");
        uint8_t drbid = Bid2Drbid (bid);        
        EpcX2Sap::UeDataParams params;
        params.sourceCellId = m_rrc->m_cellId;
        params.targetCellId = m_targetCellId;
        params.gtpTeid = GetDataRadioBearerInfo (drbid)->m_gtpTeid;
        params.ueData = p;
        m_rrc->m_x2SapProvider->SendUeData (params);
      }      
      break;
      
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;      
    }
}

std::vector<EpcX2Sap::ErabToBeSetupItem>   
UeManager::GetErabList ()
{
  NS_LOG_FUNCTION (this);
  std::vector<EpcX2Sap::ErabToBeSetupItem> ret;
  for (std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it =  m_drbMap.begin ();
       it != m_drbMap.end ();
       ++it)
    {
      EpcX2Sap::ErabToBeSetupItem etbsi;
      etbsi.erabId = it->second->m_epsBearerIdentity;
      etbsi.erabLevelQosParameters = it->second->m_epsBearer;
      etbsi.dlForwarding = false;
      etbsi.transportLayerAddress = it->second->m_transportLayerAddress;
      etbsi.gtpTeid = it->second->m_gtpTeid;
      ret.push_back (etbsi);      
    }
  return ret;
}

void
UeManager::SendUeContextRelease ()
{
  NS_LOG_FUNCTION (this);
  switch (m_state)
    {     
    case HANDOVER_PATH_SWITCH:
      NS_LOG_INFO ("Send UE CONTEXT RELEASE from target eNB to source eNB");
      EpcX2SapProvider::UeContextReleaseParams ueCtxReleaseParams;
      ueCtxReleaseParams.oldEnbUeX2apId = m_sourceX2apId;
      ueCtxReleaseParams.newEnbUeX2apId = m_rnti;
      ueCtxReleaseParams.sourceCellId = m_sourceCellId;
      m_rrc->m_x2SapProvider->SendUeContextRelease (ueCtxReleaseParams);
      SwitchToState (CONNECTED_NORMALLY);
      m_rrc->m_handoverEndOkTrace (m_imsi, m_rrc->m_cellId, m_rnti);
      break;
      
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;      
    }
}

void 
UeManager::RecvHandoverPreparationFailure (uint16_t cellId)
{
  NS_LOG_FUNCTION (this << cellId);
  switch (m_state)
    {     
    case HANDOVER_PREPARATION:   
      NS_ASSERT (cellId == m_targetCellId);
      NS_LOG_INFO ("target eNB sent HO preparation failure, aborting HO");
      SwitchToState (CONNECTED_NORMALLY);
      break;
      
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;      
    }
}

void 
UeManager::RecvSnStatusTransfer (EpcX2SapUser::SnStatusTransferParams params)
{
  NS_LOG_FUNCTION (this);
  for (std::vector<EpcX2Sap::ErabsSubjectToStatusTransferItem>::iterator erabIt 
         = params.erabsSubjectToStatusTransferList.begin ();
       erabIt != params.erabsSubjectToStatusTransferList.end ();
       ++erabIt)
    {
      // LtePdcp::Status status;
      // status.txSn = erabIt->dlPdcpSn;
      // status.rxSn = erabIt->ulPdcpSn;
      // uint8_t drbId = Bid2Drbid (erabIt->erabId);
      // std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator drbIt = m_drbMap.find (drbId);
      // NS_ASSERT_MSG (drbIt != m_drbMap.end (), "could not find DRBID " << (uint32_t) drbId);
      // drbIt->second->m_pdcp->SetStatus (status);
    }
}

void 
UeManager::RecvUeContextRelease (EpcX2SapUser::UeContextReleaseParams params)
{
  NS_LOG_FUNCTION (this);
  NS_ASSERT_MSG (m_state == HANDOVER_LEAVING, "method unexpected in state " << ToString (m_state));
  m_handoverLeavingTimeout.Cancel ();  
}


// methods forwarded from RRC SAP

void 
UeManager::CompleteSetupUe (LteEnbRrcSapProvider::CompleteSetupUeParameters params)
{
  NS_LOG_FUNCTION (this);
  m_srb0->m_rlc->SetLteRlcSapUser (params.srb0SapUser);
  m_srb1->m_pdcp->SetLtePdcpSapUser (params.srb1SapUser);
}

void
UeManager::RecvRrcConnectionRequest (LteRrcSap::RrcConnectionRequest msg)
{
  NS_LOG_FUNCTION (this);
  switch (m_state)
    {
    case INITIAL_RANDOM_ACCESS:      
      {      
        if (m_rrc->m_admitRrcConnectionRequest == true)
          {
            m_connectionTimeout.Cancel ();
            m_imsi = msg.ueIdentity;      
            if (m_rrc->m_s1SapProvider != 0)
              {
                m_rrc->m_s1SapProvider->InitialUeMessage (m_imsi, m_rnti);
              }      
            LteRrcSap::RrcConnectionSetup msg2;
            msg2.rrcTransactionIdentifier = GetNewRrcTransactionIdentifier ();
            msg2.radioResourceConfigDedicated = BuildRadioResourceConfigDedicated ();
            m_rrc->m_rrcSapUser->SendRrcConnectionSetup (m_rnti, msg2);
            RecordDataRadioBearersToBeStarted ();
            SwitchToState (CONNECTION_SETUP);
          }
        else
          {
            m_connectionTimeout.Cancel ();
            NS_LOG_INFO ("rejecting connection request for RNTI " << m_rnti);
            LteRrcSap::RrcConnectionReject rejectMsg;
            rejectMsg.waitTime = 3;
            m_rrc->m_rrcSapUser->SendRrcConnectionReject (m_rnti, rejectMsg);
            m_connectionRejectedTimeout = Simulator::Schedule (m_rrc->m_connectionRejectedTimeoutDuration, 
                                                       &LteEnbRrc::ConnectionRejectedTimeout, 
                                                       m_rrc, m_rnti);
            SwitchToState (CONNECTION_REJECTED);
          }        
      }
      break;
      
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;      
    }
}

void
UeManager::RecvRrcConnectionSetupCompleted (LteRrcSap::RrcConnectionSetupCompleted msg)
{
  NS_LOG_FUNCTION (this);
  switch (m_state)
    {
    case CONNECTION_SETUP:
      StartDataRadioBearers ();
      SwitchToState (CONNECTED_NORMALLY);
      m_rrc->m_connectionEstablishedTrace (m_imsi, m_rrc->m_cellId, m_rnti);
      break;
            
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;      
    }
}

void
UeManager::RecvRrcConnectionReconfigurationCompleted (LteRrcSap::RrcConnectionReconfigurationCompleted msg)
{
  NS_LOG_FUNCTION (this);
  switch (m_state)
    {
    case CONNECTION_RECONFIGURATION:
      StartDataRadioBearers ();   
      if (m_needTransmissionModeConfiguration)
        {          
          // configure MAC (and scheduler)
          LteEnbCmacSapProvider::UeConfig req;
          req.m_rnti = m_rnti;
          req.m_transmissionMode = m_physicalConfigDedicated.antennaInfo.transmissionMode;
          m_rrc->m_cmacSapProvider->UeUpdateConfigurationReq (req);  
          
          // configure PHY
          m_rrc->m_cphySapProvider->SetTransmissionMode (req.m_rnti, req.m_transmissionMode);
          
          m_needTransmissionModeConfiguration = false;
        }
      SwitchToState (CONNECTED_NORMALLY);
      m_rrc->m_connectionReconfigurationTrace (m_imsi, m_rrc->m_cellId, m_rnti);
      break;

    case HANDOVER_LEAVING:      
      NS_LOG_INFO ("ignoring RecvRrcConnectionReconfigurationCompleted in state " << ToString (m_state));
      break;
      
    case HANDOVER_JOINING:
      {
        m_handoverJoiningTimeout.Cancel ();
        NS_LOG_INFO ("Send PATH SWITCH REQUEST to the MME");
        EpcEnbS1SapProvider::PathSwitchRequestParameters params;
        params.rnti = m_rnti;
        params.cellId = m_rrc->m_cellId;
        params.mmeUeS1Id = m_imsi;
        SwitchToState (HANDOVER_PATH_SWITCH);
        for (std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it =  m_drbMap.begin ();
             it != m_drbMap.end ();
             ++it)
          {
            EpcEnbS1SapProvider::BearerToBeSwitched b;
            b.epsBearerId = it->second->m_epsBearerIdentity;
            b.teid =  it->second->m_gtpTeid;
            params.bearersToBeSwitched.push_back (b);
          }     
        m_rrc->m_s1SapProvider->PathSwitchRequest (params);
      }
      break;
      
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;      
    }
}
  
void 
UeManager::RecvRrcConnectionReestablishmentRequest (LteRrcSap::RrcConnectionReestablishmentRequest msg)
{
  NS_LOG_FUNCTION (this);
  switch (m_state)
    {
    case CONNECTED_NORMALLY:
      break;

    case HANDOVER_LEAVING:      
      m_handoverLeavingTimeout.Cancel ();  
      break;      
      
    default:
      NS_FATAL_ERROR ("method unexpected in state " << ToString (m_state));
      break;      
    }

  LteRrcSap::RrcConnectionReestablishment msg2;
  msg2.rrcTransactionIdentifier = GetNewRrcTransactionIdentifier ();
  msg2.radioResourceConfigDedicated = BuildRadioResourceConfigDedicated ();
  m_rrc->m_rrcSapUser->SendRrcConnectionReestablishment (m_rnti, msg2);
  SwitchToState (CONNECTION_REESTABLISHMENT);
}

void 
UeManager::RecvRrcConnectionReestablishmentComplete (LteRrcSap::RrcConnectionReestablishmentComplete msg)
{
  NS_LOG_FUNCTION (this);
  SwitchToState (CONNECTED_NORMALLY);
}

void 
UeManager::RecvMeasurementReport (LteRrcSap::MeasurementReport msg)
{
  uint8_t measId = msg.measResults.measId;
  NS_LOG_FUNCTION (this << (uint16_t) measId);
  NS_LOG_LOGIC ("measId " << (uint16_t) measId
                << " haveMeasResultNeighCells " << msg.measResults.haveMeasResultNeighCells
                << " measResultListEutra " << msg.measResults.measResultListEutra.size ());
  NS_LOG_LOGIC ("serving cellId " << m_rrc->m_cellId
                << " RSRP " << (uint16_t) msg.measResults.rsrpResult
                << " RSRQ " << (uint16_t) msg.measResults.rsrqResult);

  for (std::list <LteRrcSap::MeasResultEutra>::iterator it = msg.measResults.measResultListEutra.begin ();
       it != msg.measResults.measResultListEutra.end ();
       ++it)
    {
      NS_LOG_LOGIC ("neighbour cellId " << it->physCellId
                    << " RSRP " << (it->haveRsrpResult ? (uint16_t) it->rsrpResult : 255)
                    << " RSRQ " << (it->haveRsrqResult ? (uint16_t) it->rsrqResult : 255));
    }

  if ((m_rrc->m_handoverManagementSapProvider != 0)
      && (m_rrc->m_handoverMeasIds.find (measId) != m_rrc->m_handoverMeasIds.end ()))
    {
      // this measurement was requested by the handover algorithm
      m_rrc->m_handoverManagementSapProvider->ReportUeMeas (m_rnti,
                                                            msg.measResults);
    }

  if ((m_rrc->m_anrSapProvider != 0)
      && (m_rrc->m_anrMeasIds.find (measId) != m_rrc->m_anrMeasIds.end ()))
    {
      // this measurement was requested by the ANR function
      m_rrc->m_anrSapProvider->ReportUeMeas (msg.measResults);
    }

  // fire a trace source
  m_rrc->m_recvMeasurementReportTrace (m_imsi, m_rrc->m_cellId, m_rnti, msg);

} // end of UeManager::RecvMeasurementReport


// methods forwarded from CMAC SAP

void
UeManager::CmacUeConfigUpdateInd (LteEnbCmacSapUser::UeConfig cmacParams)
{
  NS_LOG_FUNCTION (this << m_rnti);
  // at this stage used only by the scheduler for updating txMode
  
  m_physicalConfigDedicated.antennaInfo.transmissionMode = cmacParams.m_transmissionMode;

  m_needTransmissionModeConfiguration = true;

  // reconfigure the UE RRC
  ScheduleRrcConnectionReconfiguration ();
}


// methods forwarded from PDCP SAP

void
UeManager::DoReceivePdcpSdu (LtePdcpSapUser::ReceivePdcpSduParameters params)
{
  NS_LOG_FUNCTION (this);
  if (params.lcid > 2)
    {
      // data radio bearer
      EpsBearerTag tag;
      tag.SetRnti (params.rnti);
      tag.SetBid (Lcid2Bid (params.lcid));
      params.pdcpSdu->AddPacketTag (tag);
      m_rrc->m_forwardUpCallback (params.pdcpSdu);
    }
}


uint16_t
UeManager::GetRnti (void) const
{
  return m_rnti;
}

uint64_t
UeManager::GetImsi (void) const
{
  return m_imsi;
}

uint16_t
UeManager::GetSrsConfigurationIndex (void) const
{
  return m_physicalConfigDedicated.soundingRsUlConfigDedicated.srsConfigIndex;
}

void
UeManager::SetSrsConfigurationIndex (uint16_t srsConfIndex)
{
  NS_LOG_FUNCTION (this);
  m_physicalConfigDedicated.soundingRsUlConfigDedicated.srsConfigIndex = srsConfIndex;
  m_rrc->m_cphySapProvider->SetSrsConfigurationIndex (m_rnti, srsConfIndex);
  switch (m_state)
    {
    case INITIAL_RANDOM_ACCESS:
      // do nothing, srs conf index will be correctly enforced upon
      // RRC connection establishment
      break;
      
    default:
      ScheduleRrcConnectionReconfiguration ();
      break;
    }
}

UeManager::State
UeManager::GetState (void) const
{
  return m_state;
}

uint8_t
UeManager::AddDataRadioBearerInfo (Ptr<LteDataRadioBearerInfo> drbInfo)
{
  NS_LOG_FUNCTION (this);
  const uint8_t MAX_DRB_ID = 32;  
  for (int drbid = (m_lastAllocatedDrbid + 1) % MAX_DRB_ID; 
       drbid != m_lastAllocatedDrbid; 
       drbid = (drbid + 1) % MAX_DRB_ID)
    {
      if (drbid != 0) // 0 is not allowed
        {
          if (m_drbMap.find (drbid) == m_drbMap.end ())
            {
              m_drbMap.insert (std::pair<uint8_t, Ptr<LteDataRadioBearerInfo> > (drbid, drbInfo));
              drbInfo->m_drbIdentity = drbid;
              m_lastAllocatedDrbid = drbid;
              return drbid;
            }
        }
    }
  NS_FATAL_ERROR ("no more data radio bearer ids available");
  return 0;
}

Ptr<LteDataRadioBearerInfo>
UeManager::GetDataRadioBearerInfo (uint8_t drbid)
{
  NS_LOG_FUNCTION (this << (uint32_t) drbid);
  NS_ASSERT (0 != drbid);
  std::map<uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it = m_drbMap.find (drbid);  
  NS_ABORT_IF (it == m_drbMap.end ());
  return it->second;
}


void
UeManager::RemoveDataRadioBearerInfo (uint8_t drbid)
{
  NS_LOG_FUNCTION (this << (uint32_t) drbid);
  std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it = m_drbMap.find (drbid);
  NS_ASSERT_MSG (it != m_drbMap.end (), "request to remove radio bearer with unknown drbid " << drbid);
  m_drbMap.erase (it);
}


LteRrcSap::RrcConnectionReconfiguration
UeManager::BuildRrcConnectionReconfiguration ()
{
  LteRrcSap::RrcConnectionReconfiguration msg;
  msg.rrcTransactionIdentifier = GetNewRrcTransactionIdentifier ();
  msg.haveRadioResourceConfigDedicated = true;
  msg.radioResourceConfigDedicated = BuildRadioResourceConfigDedicated ();
  msg.haveMobilityControlInfo = false;
  msg.haveMeasConfig = true;
  msg.measConfig = m_rrc->m_ueMeasConfig;

  return msg;
}

LteRrcSap::RadioResourceConfigDedicated
UeManager::BuildRadioResourceConfigDedicated ()
{
  LteRrcSap::RadioResourceConfigDedicated rrcd;

  if (m_srb1 != 0)
    {
      LteRrcSap::SrbToAddMod stam;
      stam.srbIdentity = m_srb1->m_srbIdentity;
      stam.logicalChannelConfig = m_srb1->m_logicalChannelConfig;
      rrcd.srbToAddModList.push_back (stam);
    }
    
  for (std::map <uint8_t, Ptr<LteDataRadioBearerInfo> >::iterator it = m_drbMap.begin ();
       it != m_drbMap.end ();
       ++it)
    {
      LteRrcSap::DrbToAddMod dtam;
      dtam.epsBearerIdentity = it->second->m_epsBearerIdentity;
      dtam.drbIdentity = it->second->m_drbIdentity;
      dtam.rlcConfig = it->second->m_rlcConfig;
      dtam.logicalChannelIdentity = it->second->m_logicalChannelIdentity;
      dtam.logicalChannelConfig = it->second->m_logicalChannelConfig;
      rrcd.drbToAddModList.push_back (dtam);
    }

  rrcd.havePhysicalConfigDedicated = true;
  rrcd.physicalConfigDedicated = m_physicalConfigDedicated;
  return rrcd;
}

uint8_t 
UeManager::GetNewRrcTransactionIdentifier ()
{
  return ++m_lastRrcTransactionIdentifier;
}

uint8_t 
UeManager::Lcid2Drbid (uint8_t lcid)
{
  NS_ASSERT (lcid > 2);
  return lcid - 2;
}

uint8_t 
UeManager::Drbid2Lcid (uint8_t drbid)
{
  return drbid + 2;
}
uint8_t 
UeManager::Lcid2Bid (uint8_t lcid)
{
  NS_ASSERT (lcid > 2);
  return lcid - 2;
}

uint8_t 
UeManager::Bid2Lcid (uint8_t bid)
{
  return bid + 2;
}

uint8_t 
UeManager::Drbid2Bid (uint8_t drbid)
{
  return drbid;
}

uint8_t 
UeManager::Bid2Drbid (uint8_t bid)
{
  return bid;
}


void 
UeManager::SwitchToState (State newState)
{
  NS_LOG_FUNCTION (this << ToString (newState));
  State oldState = m_state;
  m_state = newState;
  NS_LOG_INFO (this << "IMSI " << m_imsi << " RNTI " << m_rnti << " UeManager "
                    << ToString (oldState) << " --> " << ToString (newState));
  m_stateTransitionTrace (m_imsi, m_rrc->m_cellId, m_rnti, oldState, newState);
  
  switch (newState)
    {
    case INITIAL_RANDOM_ACCESS:
    case HANDOVER_JOINING:
      NS_FATAL_ERROR ("cannot switch to an initial state");      
      break;

    case CONNECTION_SETUP:
      break;

    case CONNECTED_NORMALLY:    
      {
        if (m_pendingRrcConnectionReconfiguration == true)
          {
            ScheduleRrcConnectionReconfiguration ();
          }
      }
      break;

    case CONNECTION_RECONFIGURATION:
      break;

    case CONNECTION_REESTABLISHMENT:
      break;
      
    case HANDOVER_LEAVING:
      break;      

    default:
      break;
    }
}



// eNB RRC methods

NS_OBJECT_ENSURE_REGISTERED (LteEnbRrc);

LteEnbRrc::LteEnbRrc ()
  : m_x2SapProvider (0),
    m_cmacSapProvider (0),
    m_handoverManagementSapProvider (0),
    m_anrSapProvider (0),
    m_rrcSapUser (0),
    m_macSapProvider (0),
    m_s1SapProvider (0),
    m_cphySapProvider (0),
    m_configured (false),
    m_lastAllocatedRnti (0),
    m_srsCurrentPeriodicityId (0),
    m_lastAllocatedConfigurationIndex (0),
    m_reconfigureUes (false)
{
  NS_LOG_FUNCTION (this);
  m_cmacSapUser = new EnbRrcMemberLteEnbCmacSapUser (this);
  m_handoverManagementSapUser = new MemberLteHandoverManagementSapUser<LteEnbRrc> (this);
  m_anrSapUser = new MemberLteAnrSapUser<LteEnbRrc> (this);
  m_rrcSapProvider = new MemberLteEnbRrcSapProvider<LteEnbRrc> (this);
  m_x2SapUser = new EpcX2SpecificEpcX2SapUser<LteEnbRrc> (this);
  m_s1SapUser = new MemberEpcEnbS1SapUser<LteEnbRrc> (this);
  m_cphySapUser = new MemberLteEnbCphySapUser<LteEnbRrc> (this);
}


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


void
LteEnbRrc::DoDispose ()
{
  NS_LOG_FUNCTION (this);
  m_ueMap.clear ();
  delete m_cmacSapUser;
  delete m_handoverManagementSapUser;
  delete m_anrSapUser;
  delete m_rrcSapProvider;
  delete m_x2SapUser;
  delete m_s1SapUser;
  delete m_cphySapUser;
}

TypeId
LteEnbRrc::GetTypeId (void)
{
  NS_LOG_FUNCTION ("LteEnbRrc::GetTypeId");
  static TypeId tid = TypeId ("ns3::LteEnbRrc")
    .SetParent<Object> ()
    .AddConstructor<LteEnbRrc> ()
    .AddAttribute ("UeMap", "List of UeManager by C-RNTI.",
                   ObjectMapValue (),
                   MakeObjectMapAccessor (&LteEnbRrc::m_ueMap),
                   MakeObjectMapChecker<UeManager> ())
    .AddAttribute ("DefaultTransmissionMode",
                   "The default UEs' transmission mode (0: SISO)",
                   UintegerValue (0),  // default tx-mode
                   MakeUintegerAccessor (&LteEnbRrc::m_defaultTransmissionMode),
                   MakeUintegerChecker<uint8_t> ())
    .AddAttribute ("EpsBearerToRlcMapping", 
                   "Specify which type of RLC will be used for each type of EPS bearer. ",
                   EnumValue (RLC_SM_ALWAYS),
                   MakeEnumAccessor (&LteEnbRrc::m_epsBearerToRlcMapping),
                   MakeEnumChecker (RLC_SM_ALWAYS, "RlcSmAlways",
                                    RLC_UM_ALWAYS, "RlcUmAlways",
                                    RLC_AM_ALWAYS, "RlcAmAlways",
                                    PER_BASED,     "PacketErrorRateBased"))
    .AddAttribute ("SystemInformationPeriodicity",
                   "The interval for sending system information (Time value)",
                   TimeValue (MilliSeconds (80)),
                   MakeTimeAccessor (&LteEnbRrc::m_systemInformationPeriodicity),
                   MakeTimeChecker ())

    // SRS related attributes
    .AddAttribute ("SrsPeriodicity",
                   "The SRS periodicity in milliseconds",
                   UintegerValue (40),
                   MakeUintegerAccessor (&LteEnbRrc::SetSrsPeriodicity, 
                                         &LteEnbRrc::GetSrsPeriodicity),
                   MakeUintegerChecker<uint32_t> ())

    // Timeout related attributes
    .AddAttribute ("ConnectionTimeoutDuration",
                   "After a RA attempt, if no RRC Connection Request is received before this time, the UE context is destroyed. Must account for reception of RAR and transmission of RRC CONNECTION REQUEST over UL GRANT.",
                   TimeValue (MilliSeconds (15)),
                   MakeTimeAccessor (&LteEnbRrc::m_connectionTimeoutDuration),
                   MakeTimeChecker ())
    .AddAttribute ("ConnectionRejectedTimeoutDuration",
                   "Time to wait between sending a RRC CONNECTION REJECT and destroying the UE context",
                   TimeValue (MilliSeconds (30)),
                   MakeTimeAccessor (&LteEnbRrc::m_connectionRejectedTimeoutDuration),
                   MakeTimeChecker ())
    .AddAttribute ("HandoverJoiningTimeoutDuration",
                   "After accepting a handover request, if no RRC Connection Reconfiguration Completed is received before this time, the UE context is destroyed. Must account for reception of X2 HO REQ ACK by source eNB, transmission of the Handover Command, non-contention-based random access and reception of the RRC Connection Reconfiguration Completed message.",
                   TimeValue (MilliSeconds (200)),
                   MakeTimeAccessor (&LteEnbRrc::m_handoverJoiningTimeoutDuration),
                   MakeTimeChecker ())
    .AddAttribute ("HandoverLeavingTimeoutDuration",
                   "After issuing a Handover Command, if neither RRC Connection Reestablishment nor X2 UE Context Release has been previously received, the UE context is destroyed.",
                   TimeValue (MilliSeconds (500)),
                   MakeTimeAccessor (&LteEnbRrc::m_handoverLeavingTimeoutDuration),
                   MakeTimeChecker ())

    // Cell selection related attribute
   .AddAttribute ("QRxLevMin",
                  "One of information transmitted within the SIB1 message, "
                  "indicating the required minimum RSRP level that any UE must "
                  "receive from this cell before it is allowed to camp to this "
                  "cell. The default value -70 corresponds to -140 dBm and is "
                  "the lowest possible value as defined by Section 6.3.4 of "
                  "3GPP TS 36.133. This restriction, however, only applies to "
                  "initial cell selection and EPC-enabled simulation.",
                  TypeId::ATTR_GET | TypeId::ATTR_CONSTRUCT,
                  IntegerValue (-70),
                  MakeIntegerAccessor (&LteEnbRrc::m_qRxLevMin),
                  MakeIntegerChecker<int8_t> (-70, -22))

    // Handover related attributes
    .AddAttribute ("AdmitHandoverRequest",
                   "Whether to admit an X2 handover request from another eNB",
                   BooleanValue (true),
                   MakeBooleanAccessor (&LteEnbRrc::m_admitHandoverRequest),
                   MakeBooleanChecker ())
    .AddAttribute ("AdmitRrcConnectionRequest",
                   "Whether to admit a connection request from a UE",
                   BooleanValue (true),
                   MakeBooleanAccessor (&LteEnbRrc::m_admitRrcConnectionRequest),
                   MakeBooleanChecker ())

    // UE measurements related attributes
    .AddAttribute ("RsrpFilterCoefficient",
                   "Determines the strength of smoothing effect induced by "
                   "layer 3 filtering of RSRP in all attached UE; "
                   "if set to 0, no layer 3 filtering is applicable",
                   // i.e. the variable k in 3GPP TS 36.331 section 5.5.3.2
                   UintegerValue (4),
                   MakeUintegerAccessor (&LteEnbRrc::m_rsrpFilterCoefficient),
                   MakeUintegerChecker<uint8_t> (0))
    .AddAttribute ("RsrqFilterCoefficient",
                   "Determines the strength of smoothing effect induced by "
                   "layer 3 filtering of RSRQ in all attached UE; "
                   "if set to 0, no layer 3 filtering is applicable",
                   // i.e. the variable k in 3GPP TS 36.331 section 5.5.3.2
                   UintegerValue (4),
                   MakeUintegerAccessor (&LteEnbRrc::m_rsrqFilterCoefficient),
                   MakeUintegerChecker<uint8_t> (0))

    // Trace sources
    .AddTraceSource ("NewUeContext",
                     "trace fired upon creation of a new UE context",
                     MakeTraceSourceAccessor (&LteEnbRrc::m_newUeContextTrace))
    .AddTraceSource ("ConnectionEstablished",
                     "trace fired upon successful RRC connection establishment",
                     MakeTraceSourceAccessor (&LteEnbRrc::m_connectionEstablishedTrace))
    .AddTraceSource ("ConnectionReconfiguration",
                     "trace fired upon RRC connection reconfiguration",
                     MakeTraceSourceAccessor (&LteEnbRrc::m_connectionReconfigurationTrace))
    .AddTraceSource ("HandoverStart",
                     "trace fired upon start of a handover procedure",
                     MakeTraceSourceAccessor (&LteEnbRrc::m_handoverStartTrace))
    .AddTraceSource ("HandoverEndOk",
                     "trace fired upon successful termination of a handover procedure",
                     MakeTraceSourceAccessor (&LteEnbRrc::m_handoverEndOkTrace))
    .AddTraceSource ("RecvMeasurementReport",
                     "trace fired when measurement report is received",
                     MakeTraceSourceAccessor (&LteEnbRrc::m_recvMeasurementReportTrace))
  ;
  return tid;
}

void
LteEnbRrc::SetEpcX2SapProvider (EpcX2SapProvider * s)
{
  NS_LOG_FUNCTION (this << s);
  m_x2SapProvider = s;
}

EpcX2SapUser*
LteEnbRrc::GetEpcX2SapUser ()
{
  NS_LOG_FUNCTION (this);
  return m_x2SapUser;
}

void
LteEnbRrc::SetLteEnbCmacSapProvider (LteEnbCmacSapProvider * s)
{
  NS_LOG_FUNCTION (this << s);
  m_cmacSapProvider = s;
}

LteEnbCmacSapUser*
LteEnbRrc::GetLteEnbCmacSapUser ()
{
  NS_LOG_FUNCTION (this);
  return m_cmacSapUser;
}

void
LteEnbRrc::SetLteHandoverManagementSapProvider (LteHandoverManagementSapProvider * s)
{
  NS_LOG_FUNCTION (this << s);
  m_handoverManagementSapProvider = s;
}

LteHandoverManagementSapUser*
LteEnbRrc::GetLteHandoverManagementSapUser ()
{
  NS_LOG_FUNCTION (this);
  return m_handoverManagementSapUser;
}

void
LteEnbRrc::SetLteAnrSapProvider (LteAnrSapProvider * s)
{
  NS_LOG_FUNCTION (this << s);
  m_anrSapProvider = s;
}

LteAnrSapUser*
LteEnbRrc::GetLteAnrSapUser ()
{
  NS_LOG_FUNCTION (this);
  return m_anrSapUser;
}

void
LteEnbRrc::SetLteEnbRrcSapUser (LteEnbRrcSapUser * s)
{
  NS_LOG_FUNCTION (this << s);
  m_rrcSapUser = s;
}

LteEnbRrcSapProvider*
LteEnbRrc::GetLteEnbRrcSapProvider ()
{
  NS_LOG_FUNCTION (this);
  return m_rrcSapProvider;
}

void
LteEnbRrc::SetLteMacSapProvider (LteMacSapProvider * s)
{
  NS_LOG_FUNCTION (this);
  m_macSapProvider = s;
}

void 
LteEnbRrc::SetS1SapProvider (EpcEnbS1SapProvider * s)
{
  m_s1SapProvider = s;
}

  
EpcEnbS1SapUser* 
LteEnbRrc::GetS1SapUser ()
{
  return m_s1SapUser;
}

void
LteEnbRrc::SetLteEnbCphySapProvider (LteEnbCphySapProvider * s)
{
  NS_LOG_FUNCTION (this << s);
  m_cphySapProvider = s;
}

LteEnbCphySapUser*
LteEnbRrc::GetLteEnbCphySapUser ()
{
  NS_LOG_FUNCTION (this);
  return m_cphySapUser;
}

Ptr<UeManager>
LteEnbRrc::GetUeManager (uint16_t rnti)
{
  NS_LOG_FUNCTION (this << (uint32_t) rnti);
  NS_ASSERT (0 != rnti);
  std::map<uint16_t, Ptr<UeManager> >::iterator it = m_ueMap.find (rnti);
  NS_ASSERT_MSG (it != m_ueMap.end (), "RNTI " << rnti << " not found in eNB with cellId " << m_cellId);
  return it->second;
}

uint8_t
LteEnbRrc::AddUeMeasReportConfig (LteRrcSap::ReportConfigEutra config)
{
  NS_LOG_FUNCTION (this);

  // SANITY CHECK

  NS_ASSERT_MSG (m_ueMeasConfig.measIdToAddModList.size () == m_ueMeasConfig.reportConfigToAddModList.size (),
                 "Measurement identities and reporting configuration should not have different quantity");

  if (Simulator::Now () != Seconds (0))
    {
      NS_FATAL_ERROR ("AddUeMeasReportConfig may not be called after the simulation has run");
    }

  // INPUT VALIDATION

  switch (config.triggerQuantity)
    {
    case LteRrcSap::ReportConfigEutra::RSRP:
      if ((config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A5)
          && (config.threshold2.choice != LteRrcSap::ThresholdEutra::THRESHOLD_RSRP))
        {
          NS_FATAL_ERROR ("The given triggerQuantity (RSRP) does not match with the given threshold2.choice");
        }

      if (((config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A1)
           || (config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A2)
           || (config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A4)
           || (config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A5))
          && (config.threshold1.choice != LteRrcSap::ThresholdEutra::THRESHOLD_RSRP))
        {
          NS_FATAL_ERROR ("The given triggerQuantity (RSRP) does not match with the given threshold1.choice");
        }
      break;

    case LteRrcSap::ReportConfigEutra::RSRQ:
      if ((config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A5)
          && (config.threshold2.choice != LteRrcSap::ThresholdEutra::THRESHOLD_RSRQ))
        {
          NS_FATAL_ERROR ("The given triggerQuantity (RSRQ) does not match with the given threshold2.choice");
        }

      if (((config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A1)
           || (config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A2)
           || (config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A4)
           || (config.eventId == LteRrcSap::ReportConfigEutra::EVENT_A5))
          && (config.threshold1.choice != LteRrcSap::ThresholdEutra::THRESHOLD_RSRQ))
        {
          NS_FATAL_ERROR ("The given triggerQuantity (RSRQ) does not match with the given threshold1.choice");
        }
      break;

    default:
      NS_FATAL_ERROR ("unsupported triggerQuantity");
      break;
    }

  if (config.purpose != LteRrcSap::ReportConfigEutra::REPORT_STRONGEST_CELLS)
    {
      NS_FATAL_ERROR ("Only REPORT_STRONGEST_CELLS purpose is supported");
    }

  if (config.reportQuantity != LteRrcSap::ReportConfigEutra::BOTH)
    {
      NS_LOG_WARN ("reportQuantity = BOTH will be used instead of the given reportQuantity");
    }

  uint8_t nextId = m_ueMeasConfig.reportConfigToAddModList.size () + 1;

  // create the reporting configuration
  LteRrcSap::ReportConfigToAddMod reportConfig;
  reportConfig.reportConfigId = nextId;
  reportConfig.reportConfigEutra = config;

  // create the measurement identity
  LteRrcSap::MeasIdToAddMod measId;
  measId.measId = nextId;
  measId.measObjectId = 1;
  measId.reportConfigId = nextId;

  // add both to the list of UE measurement configuration
  m_ueMeasConfig.reportConfigToAddModList.push_back (reportConfig);
  m_ueMeasConfig.measIdToAddModList.push_back (measId);

  return nextId;
}

void
LteEnbRrc::ConfigureCell (uint8_t ulBandwidth, uint8_t dlBandwidth,
                          uint16_t ulEarfcn, uint16_t dlEarfcn, uint16_t cellId)
{
  NS_LOG_FUNCTION (this << (uint16_t) ulBandwidth << (uint16_t) dlBandwidth
                        << ulEarfcn << dlEarfcn << cellId);
  NS_ASSERT (!m_configured);
  m_cmacSapProvider->ConfigureMac (ulBandwidth, dlBandwidth);
  m_cphySapProvider->SetBandwidth (ulBandwidth, dlBandwidth);
  m_cphySapProvider->SetEarfcn (ulEarfcn, dlEarfcn);
  m_dlEarfcn = dlEarfcn;
  m_ulEarfcn = ulEarfcn;
  m_dlBandwidth = dlBandwidth;
  m_ulBandwidth = ulBandwidth;
  m_cellId = cellId;
  m_cphySapProvider->SetCellId (cellId);

  /*
   * Initializing the list of UE measurement configuration (m_ueMeasConfig).
   * Only intra-frequency measurements are supported, so only one measurement
   * object is created.
   */

  LteRrcSap::MeasObjectToAddMod measObject;
  measObject.measObjectId = 1;
  measObject.measObjectEutra.carrierFreq = m_dlEarfcn;
  measObject.measObjectEutra.allowedMeasBandwidth = m_dlBandwidth;
  measObject.measObjectEutra.presenceAntennaPort1 = false;
  measObject.measObjectEutra.neighCellConfig = 0;
  measObject.measObjectEutra.offsetFreq = 0;
  measObject.measObjectEutra.haveCellForWhichToReportCGI = false;

  m_ueMeasConfig.measObjectToAddModList.push_back (measObject);
  m_ueMeasConfig.haveQuantityConfig = true;
  m_ueMeasConfig.quantityConfig.filterCoefficientRSRP = m_rsrpFilterCoefficient;
  m_ueMeasConfig.quantityConfig.filterCoefficientRSRQ = m_rsrqFilterCoefficient;
  m_ueMeasConfig.haveMeasGapConfig = false;
  m_ueMeasConfig.haveSmeasure = false;
  m_ueMeasConfig.haveSpeedStatePars = false;

  // Enabling MIB transmission
  LteRrcSap::MasterInformationBlock mib;
  mib.dlBandwidth = m_dlBandwidth;
  m_cphySapProvider->SetMasterInformationBlock (mib);

  // Enabling SIB1 transmission with default values
  m_sib1.cellAccessRelatedInfo.cellIdentity = cellId;
  m_sib1.cellAccessRelatedInfo.csgIndication = false;
  m_sib1.cellAccessRelatedInfo.csgIdentity = 0;
  m_sib1.cellAccessRelatedInfo.plmnIdentityInfo.plmnIdentity = 0; // not used
  m_sib1.cellSelectionInfo.qQualMin = -34; // not used, set as minimum value
  m_sib1.cellSelectionInfo.qRxLevMin = m_qRxLevMin; // set as minimum value
  m_cphySapProvider->SetSystemInformationBlockType1 (m_sib1);

  /*
   * Enabling transmission of other SIB. The first time System Information is
   * transmitted is arbitrarily assumed to be at +0.016s, and then it will be
   * regularly transmitted every 80 ms by default (set the
   * SystemInformationPeriodicity attribute to configure this).
   */
  Simulator::Schedule (MilliSeconds (16), &LteEnbRrc::SendSystemInformation, this);

  m_configured = true;

}


void
LteEnbRrc::SetCellId (uint16_t cellId)
{
  m_cellId = cellId;

  // update SIB1 too
  m_sib1.cellAccessRelatedInfo.cellIdentity = cellId;
  m_cphySapProvider->SetSystemInformationBlockType1 (m_sib1);
}

bool
LteEnbRrc::SendData (Ptr<Packet> packet)
{
  NS_LOG_FUNCTION (this << packet);

  EpsBearerTag tag;
  bool found = packet->RemovePacketTag (tag);
  NS_ASSERT_MSG (found, "no EpsBearerTag found in packet to be sent");
  Ptr<UeManager> ueManager = GetUeManager (tag.GetRnti ());
  ueManager->SendData (tag.GetBid (), packet);

  return true;
}

void 
LteEnbRrc::SetForwardUpCallback (Callback <void, Ptr<Packet> > cb)
{
  m_forwardUpCallback = cb;
}

void
LteEnbRrc::ConnectionTimeout (uint16_t rnti)
{
  NS_LOG_FUNCTION (this << rnti);
  NS_ASSERT_MSG (GetUeManager (rnti)->GetState () == UeManager::INITIAL_RANDOM_ACCESS, 
                 "ConnectionTimeout in unexpected state " << ToString (GetUeManager (rnti)->GetState ()));
  RemoveUe (rnti);
}

void
LteEnbRrc::ConnectionRejectedTimeout (uint16_t rnti)
{
  NS_LOG_FUNCTION (this << rnti);
  NS_ASSERT_MSG (GetUeManager (rnti)->GetState () == UeManager::CONNECTION_REJECTED,
                 "ConnectionTimeout in unexpected state " << ToString (GetUeManager (rnti)->GetState ()));
  RemoveUe (rnti);
}

void
LteEnbRrc::HandoverJoiningTimeout (uint16_t rnti)
{
  NS_LOG_FUNCTION (this << rnti);
  NS_ASSERT_MSG (GetUeManager (rnti)->GetState () == UeManager::HANDOVER_JOINING, 
                 "HandoverJoiningTimeout in unexpected state " << ToString (GetUeManager (rnti)->GetState ()));
  RemoveUe (rnti);
}

void
LteEnbRrc::HandoverLeavingTimeout (uint16_t rnti)
{
  NS_LOG_FUNCTION (this << rnti);
  NS_ASSERT_MSG (GetUeManager (rnti)->GetState () == UeManager::HANDOVER_LEAVING, 
                 "HandoverLeavingTimeout in unexpected state " << ToString (GetUeManager (rnti)->GetState ()));
  RemoveUe (rnti);
}

void
LteEnbRrc::SendHandoverRequest (uint16_t rnti, uint16_t cellId)
{
  NS_LOG_FUNCTION (this << rnti << cellId);
  NS_LOG_LOGIC ("Request to send HANDOVER REQUEST");
  NS_ASSERT (m_configured);

  Ptr<UeManager> ueManager = GetUeManager (rnti);
  ueManager->PrepareHandover (cellId);
 
}

void 
LteEnbRrc::DoCompleteSetupUe (uint16_t rnti, LteEnbRrcSapProvider::CompleteSetupUeParameters params)
{
  NS_LOG_FUNCTION (this << rnti);
  GetUeManager (rnti)->CompleteSetupUe (params);
}

void
LteEnbRrc::DoRecvRrcConnectionRequest (uint16_t rnti, LteRrcSap::RrcConnectionRequest msg)
{
  NS_LOG_FUNCTION (this << rnti);
  GetUeManager (rnti)->RecvRrcConnectionRequest (msg);
}

void
LteEnbRrc::DoRecvRrcConnectionSetupCompleted (uint16_t rnti, LteRrcSap::RrcConnectionSetupCompleted msg)
{
  NS_LOG_FUNCTION (this << rnti);
  GetUeManager (rnti)->RecvRrcConnectionSetupCompleted (msg);
}

void
LteEnbRrc::DoRecvRrcConnectionReconfigurationCompleted (uint16_t rnti, LteRrcSap::RrcConnectionReconfigurationCompleted msg)
{
  NS_LOG_FUNCTION (this << rnti);
  GetUeManager (rnti)->RecvRrcConnectionReconfigurationCompleted (msg);
}
  
void 
LteEnbRrc::DoRecvRrcConnectionReestablishmentRequest (uint16_t rnti, LteRrcSap::RrcConnectionReestablishmentRequest msg)
{
  NS_LOG_FUNCTION (this << rnti);
  GetUeManager (rnti)->RecvRrcConnectionReestablishmentRequest (msg);  
}

void 
LteEnbRrc::DoRecvRrcConnectionReestablishmentComplete (uint16_t rnti, LteRrcSap::RrcConnectionReestablishmentComplete msg)
{
  NS_LOG_FUNCTION (this << rnti);
  GetUeManager (rnti)->RecvRrcConnectionReestablishmentComplete (msg);
}

void 
LteEnbRrc::DoRecvMeasurementReport (uint16_t rnti, LteRrcSap::MeasurementReport msg)
{
  NS_LOG_FUNCTION (this << rnti);
  GetUeManager (rnti)->RecvMeasurementReport (msg);
}

void 
LteEnbRrc::DoDataRadioBearerSetupRequest (EpcEnbS1SapUser::DataRadioBearerSetupRequestParameters request)
{
  Ptr<UeManager> ueManager = GetUeManager (request.rnti);
  ueManager->SetupDataRadioBearer (request.bearer, request.bearerId, request.gtpTeid, request.transportLayerAddress);       
}

void 
LteEnbRrc::DoPathSwitchRequestAcknowledge (EpcEnbS1SapUser::PathSwitchRequestAcknowledgeParameters params)
{
  Ptr<UeManager> ueManager = GetUeManager (params.rnti);
  ueManager->SendUeContextRelease ();
}

void
LteEnbRrc::DoRecvHandoverRequest (EpcX2SapUser::HandoverRequestParams req)
{
  NS_LOG_FUNCTION (this);

  NS_LOG_LOGIC ("Recv X2 message: HANDOVER REQUEST");

  NS_LOG_LOGIC ("oldEnbUeX2apId = " << req.oldEnbUeX2apId);
  NS_LOG_LOGIC ("sourceCellId = " << req.sourceCellId);
  NS_LOG_LOGIC ("targetCellId = " << req.targetCellId);
  NS_LOG_LOGIC ("mmeUeS1apId = " << req.mmeUeS1apId);

  NS_ASSERT (req.targetCellId == m_cellId);

  if (m_admitHandoverRequest == false)
    {
      NS_LOG_INFO ("rejecting handover request from cellId " << req.sourceCellId);
      EpcX2Sap::HandoverPreparationFailureParams res;
      res.oldEnbUeX2apId =  req.oldEnbUeX2apId;
      res.sourceCellId = req.sourceCellId ;
      res.targetCellId = req.targetCellId ;
      res.cause = 0;
      res.criticalityDiagnostics = 0;
      m_x2SapProvider->SendHandoverPreparationFailure (res);
      return;
    }
  
  uint16_t rnti = AddUe (UeManager::HANDOVER_JOINING);
  LteEnbCmacSapProvider::AllocateNcRaPreambleReturnValue anrcrv = m_cmacSapProvider->AllocateNcRaPreamble (rnti);
  if (anrcrv.valid == false)
    {
      NS_LOG_INFO (this << "failed to allocate a preamble for non-contention based RA => cannot accept HO");
      RemoveUe (rnti);
      NS_FATAL_ERROR ("should trigger HO Preparation Failure, but it is not implemented");
      return;
    }    

  Ptr<UeManager> ueManager = GetUeManager (rnti);
  ueManager->SetSource (req.sourceCellId, req.oldEnbUeX2apId);
  ueManager->SetImsi (req.mmeUeS1apId);

  EpcX2SapProvider::HandoverRequestAckParams ackParams;
  ackParams.oldEnbUeX2apId = req.oldEnbUeX2apId;
  ackParams.newEnbUeX2apId = rnti;
  ackParams.sourceCellId = req.sourceCellId;
  ackParams.targetCellId = req.targetCellId;

  for (std::vector <EpcX2Sap::ErabToBeSetupItem>::iterator it = req.bearers.begin ();
       it != req.bearers.end ();
       ++it)
    {
      ueManager->SetupDataRadioBearer (it->erabLevelQosParameters, it->erabId, it->gtpTeid, it->transportLayerAddress);
      EpcX2Sap::ErabAdmittedItem i;
      i.erabId = it->erabId;
      ackParams.admittedBearers.push_back (i);
    }

  LteRrcSap::RrcConnectionReconfiguration handoverCommand = ueManager->GetRrcConnectionReconfigurationForHandover ();
  handoverCommand.haveMobilityControlInfo = true;
  handoverCommand.mobilityControlInfo.targetPhysCellId = m_cellId;
  handoverCommand.mobilityControlInfo.haveCarrierFreq = true;
  handoverCommand.mobilityControlInfo.carrierFreq.dlCarrierFreq = m_dlEarfcn;
  handoverCommand.mobilityControlInfo.carrierFreq.ulCarrierFreq = m_ulEarfcn;
  handoverCommand.mobilityControlInfo.haveCarrierBandwidth = true;
  handoverCommand.mobilityControlInfo.carrierBandwidth.dlBandwidth = m_dlBandwidth;
  handoverCommand.mobilityControlInfo.carrierBandwidth.ulBandwidth = m_ulBandwidth;
  handoverCommand.mobilityControlInfo.newUeIdentity = rnti;
  handoverCommand.mobilityControlInfo.haveRachConfigDedicated = true;
  handoverCommand.mobilityControlInfo.rachConfigDedicated.raPreambleIndex = anrcrv.raPreambleId;
  handoverCommand.mobilityControlInfo.rachConfigDedicated.raPrachMaskIndex = anrcrv.raPrachMaskIndex;

  LteEnbCmacSapProvider::RachConfig rc = m_cmacSapProvider->GetRachConfig ();
  handoverCommand.mobilityControlInfo.radioResourceConfigCommon.rachConfigCommon.preambleInfo.numberOfRaPreambles = rc.numberOfRaPreambles;
  handoverCommand.mobilityControlInfo.radioResourceConfigCommon.rachConfigCommon.raSupervisionInfo.preambleTransMax = rc.preambleTransMax;
  handoverCommand.mobilityControlInfo.radioResourceConfigCommon.rachConfigCommon.raSupervisionInfo.raResponseWindowSize = rc.raResponseWindowSize;

  Ptr<Packet> encodedHandoverCommand = m_rrcSapUser->EncodeHandoverCommand (handoverCommand);

  ackParams.rrcContext = encodedHandoverCommand;

  NS_LOG_LOGIC ("Send X2 message: HANDOVER REQUEST ACK");

  NS_LOG_LOGIC ("oldEnbUeX2apId = " << ackParams.oldEnbUeX2apId);
  NS_LOG_LOGIC ("newEnbUeX2apId = " << ackParams.newEnbUeX2apId);
  NS_LOG_LOGIC ("sourceCellId = " << ackParams.sourceCellId);
  NS_LOG_LOGIC ("targetCellId = " << ackParams.targetCellId);

  m_x2SapProvider->SendHandoverRequestAck (ackParams);
}

void
LteEnbRrc::DoRecvHandoverRequestAck (EpcX2SapUser::HandoverRequestAckParams params)
{
  NS_LOG_FUNCTION (this);
  
  NS_LOG_LOGIC ("Recv X2 message: HANDOVER REQUEST ACK");
  
  NS_LOG_LOGIC ("oldEnbUeX2apId = " << params.oldEnbUeX2apId);
  NS_LOG_LOGIC ("newEnbUeX2apId = " << params.newEnbUeX2apId);
  NS_LOG_LOGIC ("sourceCellId = " << params.sourceCellId);
  NS_LOG_LOGIC ("targetCellId = " << params.targetCellId);

  uint16_t rnti = params.oldEnbUeX2apId;
  Ptr<UeManager> ueManager = GetUeManager (rnti);  
  ueManager->RecvHandoverRequestAck (params);
}

void
LteEnbRrc::DoRecvHandoverPreparationFailure (EpcX2SapUser::HandoverPreparationFailureParams params)
{
  NS_LOG_FUNCTION (this);

  NS_LOG_LOGIC ("Recv X2 message: HANDOVER PREPARATION FAILURE");

  NS_LOG_LOGIC ("oldEnbUeX2apId = " << params.oldEnbUeX2apId);
  NS_LOG_LOGIC ("sourceCellId = " << params.sourceCellId);
  NS_LOG_LOGIC ("targetCellId = " << params.targetCellId);
  NS_LOG_LOGIC ("cause = " << params.cause);
  NS_LOG_LOGIC ("criticalityDiagnostics = " << params.criticalityDiagnostics);

  uint16_t rnti = params.oldEnbUeX2apId;
  Ptr<UeManager> ueManager = GetUeManager (rnti);
  ueManager->RecvHandoverPreparationFailure (params.targetCellId);
}

void
LteEnbRrc::DoRecvSnStatusTransfer (EpcX2SapUser::SnStatusTransferParams params)
{
  NS_LOG_FUNCTION (this);

  NS_LOG_LOGIC ("Recv X2 message: SN STATUS TRANSFER");

  NS_LOG_LOGIC ("oldEnbUeX2apId = " << params.oldEnbUeX2apId);
  NS_LOG_LOGIC ("newEnbUeX2apId = " << params.newEnbUeX2apId);
  NS_LOG_LOGIC ("erabsSubjectToStatusTransferList size = " << params.erabsSubjectToStatusTransferList.size ());

  uint16_t rnti = params.newEnbUeX2apId;
  Ptr<UeManager> ueManager = GetUeManager (rnti);
  ueManager->RecvSnStatusTransfer (params);
}

void
LteEnbRrc::DoRecvUeContextRelease (EpcX2SapUser::UeContextReleaseParams params)
{
  NS_LOG_FUNCTION (this);

  NS_LOG_LOGIC ("Recv X2 message: UE CONTEXT RELEASE");

  NS_LOG_LOGIC ("oldEnbUeX2apId = " << params.oldEnbUeX2apId);
  NS_LOG_LOGIC ("newEnbUeX2apId = " << params.newEnbUeX2apId);

  uint16_t rnti = params.oldEnbUeX2apId;
  GetUeManager (rnti)->RecvUeContextRelease (params);
  RemoveUe (rnti);
}

void
LteEnbRrc::DoRecvLoadInformation (EpcX2SapUser::LoadInformationParams params)
{
  NS_LOG_FUNCTION (this);

  NS_LOG_LOGIC ("Recv X2 message: LOAD INFORMATION");

  NS_LOG_LOGIC ("Number of cellInformationItems = " << params.cellInformationList.size ());

  NS_ASSERT ("Processing of LOAD INFORMATION X2 message IS NOT IMPLEMENTED");
}

void
LteEnbRrc::DoRecvResourceStatusUpdate (EpcX2SapUser::ResourceStatusUpdateParams params)
{
  NS_LOG_FUNCTION (this);

  NS_LOG_LOGIC ("Recv X2 message: RESOURCE STATUS UPDATE");

  NS_LOG_LOGIC ("Number of cellMeasurementResultItems = " << params.cellMeasurementResultList.size ());

  NS_ASSERT ("Processing of RESOURCE STATUS UPDATE X2 message IS NOT IMPLEMENTED");
}

void
LteEnbRrc::DoRecvUeData (EpcX2SapUser::UeDataParams params)
{
  NS_LOG_FUNCTION (this);

  NS_LOG_LOGIC ("Recv UE DATA FORWARDING through X2 interface");
  NS_LOG_LOGIC ("sourceCellId = " << params.sourceCellId);
  NS_LOG_LOGIC ("targetCellId = " << params.targetCellId);
  NS_LOG_LOGIC ("gtpTeid = " << params.gtpTeid);
  NS_LOG_LOGIC ("ueData = " << params.ueData);
  NS_LOG_LOGIC ("ueData size = " << params.ueData->GetSize ());

  std::map<uint32_t, X2uTeidInfo>::iterator 
    teidInfoIt = m_x2uTeidInfoMap.find (params.gtpTeid);
  if (teidInfoIt != m_x2uTeidInfoMap.end ())    
    {
      GetUeManager (teidInfoIt->second.rnti)->SendData (teidInfoIt->second.drbid, params.ueData);
    }
  else
    {
      NS_FATAL_ERROR ("X2-U data received but no X2uTeidInfo found");
    }
}


uint16_t 
LteEnbRrc::DoAllocateTemporaryCellRnti ()
{
  NS_LOG_FUNCTION (this);
  return AddUe (UeManager::INITIAL_RANDOM_ACCESS);
}

void
LteEnbRrc::DoRrcConfigurationUpdateInd (LteEnbCmacSapUser::UeConfig cmacParams)
{
  Ptr<UeManager> ueManager = GetUeManager (cmacParams.m_rnti);
  ueManager->CmacUeConfigUpdateInd (cmacParams);
}

void
LteEnbRrc::DoNotifyLcConfigResult (uint16_t rnti, uint8_t lcid, bool success)
{
  NS_LOG_FUNCTION (this << (uint32_t) rnti);
  NS_FATAL_ERROR ("not implemented");
}


uint8_t
LteEnbRrc::DoAddUeMeasReportConfigForHandover (LteRrcSap::ReportConfigEutra reportConfig)
{
  NS_LOG_FUNCTION (this);
  uint8_t measId = AddUeMeasReportConfig (reportConfig);
  m_handoverMeasIds.insert (measId);
  return measId;
}

void
LteEnbRrc::DoTriggerHandover (uint16_t rnti, uint16_t targetCellId)
{
  NS_LOG_FUNCTION (this << rnti << targetCellId);

  bool isHandoverAllowed = true;

  if (m_anrSapProvider != 0)
    {
      // ensure that proper neighbour relationship exists between source and target cells
      bool noHo = m_anrSapProvider->GetNoHo (targetCellId);
      bool noX2 = m_anrSapProvider->GetNoX2 (targetCellId);
      NS_LOG_DEBUG (this << " cellId=" << m_cellId
                         << " targetCellId=" << targetCellId
                         << " NRT.NoHo=" << noHo << " NRT.NoX2=" << noX2);

      if (noHo || noX2)
        {
          isHandoverAllowed = false;
          NS_LOG_LOGIC (this << " handover to cell " << targetCellId
                             << " is not allowed by ANR");
        }
    }

  Ptr<UeManager> ueManager = GetUeManager (rnti);
  NS_ASSERT_MSG (ueManager != 0, "Cannot find UE context with RNTI " << rnti);

  if (ueManager->GetState () != UeManager::CONNECTED_NORMALLY)
    {
      isHandoverAllowed = false;
      NS_LOG_LOGIC (this << " handover is not allowed because the UE"
                         << " rnti=" << rnti << " is in "
                         << ToString (ueManager->GetState ()) << " state");
    }

  if (isHandoverAllowed)
    {
      // initiate handover execution
      ueManager->PrepareHandover (targetCellId);
    }
}

uint8_t
LteEnbRrc::DoAddUeMeasReportConfigForAnr (LteRrcSap::ReportConfigEutra reportConfig)
{
  NS_LOG_FUNCTION (this);
  uint8_t measId = AddUeMeasReportConfig (reportConfig);
  m_anrMeasIds.insert (measId);
  return measId;
}



uint16_t
LteEnbRrc::AddUe (UeManager::State state)
{
  NS_LOG_FUNCTION (this);
  bool found = false;
  uint16_t rnti;
  for (rnti = m_lastAllocatedRnti + 1; 
       (rnti != m_lastAllocatedRnti - 1) && (!found);
       ++rnti)
    {
      if ((rnti != 0) && (m_ueMap.find (rnti) == m_ueMap.end ()))
        {
          found = true;
          break;
        }
    }

  NS_ASSERT_MSG (found, "no more RNTIs available (do you have more than 65535 UEs in a cell?)");
  m_lastAllocatedRnti = rnti;
  Ptr<UeManager> ueManager = CreateObject<UeManager> (this, rnti, state);
  m_ueMap.insert (std::pair<uint16_t, Ptr<UeManager> > (rnti, ueManager));
  ueManager->Initialize ();
  NS_LOG_DEBUG (this << " New UE RNTI " << rnti << " cellId " << m_cellId << " srs CI " << ueManager->GetSrsConfigurationIndex ());      
  m_newUeContextTrace (m_cellId, rnti);      
  return rnti;
}

void
LteEnbRrc::RemoveUe (uint16_t rnti)
{
  NS_LOG_FUNCTION (this << (uint32_t) rnti);
  std::map <uint16_t, Ptr<UeManager> >::iterator it = m_ueMap.find (rnti);
  NS_ASSERT_MSG (it != m_ueMap.end (), "request to remove UE info with unknown rnti " << rnti);
  uint16_t srsCi = (*it).second->GetSrsConfigurationIndex ();
  m_ueMap.erase (it);
  m_cmacSapProvider->RemoveUe (rnti);
  m_cphySapProvider->RemoveUe (rnti);
  if (m_s1SapProvider != 0)
    {
      m_s1SapProvider->UeContextRelease (rnti);
    }
  // need to do this after UeManager has been deleted
  RemoveSrsConfigurationIndex (srsCi); 
}

TypeId
LteEnbRrc::GetRlcType (EpsBearer bearer)
{
  switch (m_epsBearerToRlcMapping)
    {
    case RLC_SM_ALWAYS:
      return LteRlcSm::GetTypeId ();
      break;

    case  RLC_UM_ALWAYS:
      return LteRlcUm::GetTypeId ();
      break;

    case RLC_AM_ALWAYS:
      return LteRlcAm::GetTypeId ();
      break;

    case PER_BASED:
      if (bearer.GetPacketErrorLossRate () > 1.0e-5)
        {
          return LteRlcUm::GetTypeId ();
        }
      else
        {
          return LteRlcAm::GetTypeId ();
        }
      break;

    default:
      return LteRlcSm::GetTypeId ();
      break;
    }
}


void
LteEnbRrc::AddX2Neighbour (uint16_t cellId)
{
  NS_LOG_FUNCTION (this << cellId);

  if (m_anrSapProvider != 0)
    {
      m_anrSapProvider->AddNeighbourRelation (cellId);
    }
}

void
LteEnbRrc::SetCsgId (uint32_t csgId, bool csgIndication)
{
  NS_LOG_FUNCTION (this << csgId << csgIndication);
  m_sib1.cellAccessRelatedInfo.csgIdentity = csgId;
  m_sib1.cellAccessRelatedInfo.csgIndication = csgIndication;
  m_cphySapProvider->SetSystemInformationBlockType1 (m_sib1);
}


// from 3GPP TS 36.213 table 8.2-1 UE Specific SRS Periodicity
static const uint8_t SRS_ENTRIES = 9;
static const uint16_t g_srsPeriodicity[SRS_ENTRIES] = {0, 2, 5, 10, 20, 40,  80, 160, 320};
static const uint16_t g_srsCiLow[SRS_ENTRIES] =       {0, 0, 2,  7, 17, 37,  77, 157, 317};
static const uint16_t g_srsCiHigh[SRS_ENTRIES] =      {0, 1, 6, 16, 36, 76, 156, 316, 636};

void 
LteEnbRrc::SetSrsPeriodicity (uint32_t p)
{
  NS_LOG_FUNCTION (this << p);
  for (uint32_t id = 1; id < SRS_ENTRIES; ++id)
    {
      if (g_srsPeriodicity[id] == p)
        {
          m_srsCurrentPeriodicityId = id;
          return;
        }
    }
  // no match found
  std::ostringstream allowedValues;
  for (uint32_t id = 1; id < SRS_ENTRIES; ++id)
    {
      allowedValues << g_srsPeriodicity[id] << " ";
    }
  NS_FATAL_ERROR ("illecit SRS periodicity value " << p << ". Allowed values: " << allowedValues.str ());
}

uint32_t 
LteEnbRrc::GetSrsPeriodicity () const
{
  NS_LOG_FUNCTION (this);
  NS_ASSERT (m_srsCurrentPeriodicityId > 0);
  NS_ASSERT (m_srsCurrentPeriodicityId < SRS_ENTRIES);
  return g_srsPeriodicity[m_srsCurrentPeriodicityId];
}


uint16_t
LteEnbRrc::GetNewSrsConfigurationIndex ()
{
  NS_LOG_FUNCTION (this << m_ueSrsConfigurationIndexSet.size ());
  // SRS
  NS_ASSERT (m_srsCurrentPeriodicityId > 0);
  NS_ASSERT (m_srsCurrentPeriodicityId < SRS_ENTRIES);
  NS_LOG_DEBUG (this << " SRS p " << g_srsPeriodicity[m_srsCurrentPeriodicityId] << " set " << m_ueSrsConfigurationIndexSet.size ());
  if (m_ueSrsConfigurationIndexSet.size () >= g_srsPeriodicity[m_srsCurrentPeriodicityId])
    {
      NS_FATAL_ERROR ("too many UEs (" << m_ueSrsConfigurationIndexSet.size () + 1 
                      << ") for current SRS periodicity " 
                      <<  g_srsPeriodicity[m_srsCurrentPeriodicityId]
                      << ", consider increasing the value of ns3::LteEnbRrc::SrsPeriodicity");
    }

  if (m_ueSrsConfigurationIndexSet.empty ())
    {
      // first entry
      m_lastAllocatedConfigurationIndex = g_srsCiLow[m_srsCurrentPeriodicityId];
      m_ueSrsConfigurationIndexSet.insert (m_lastAllocatedConfigurationIndex);
    }
  else
    {
      // find a CI from the available ones
      std::set<uint16_t>::reverse_iterator rit = m_ueSrsConfigurationIndexSet.rbegin ();
      NS_ASSERT (rit != m_ueSrsConfigurationIndexSet.rend ());
      NS_LOG_DEBUG (this << " lower bound " << (*rit) << " of " << g_srsCiHigh[m_srsCurrentPeriodicityId]);
      if ((*rit) < g_srsCiHigh[m_srsCurrentPeriodicityId])
        {
          // got it from the upper bound
          m_lastAllocatedConfigurationIndex = (*rit) + 1;
          m_ueSrsConfigurationIndexSet.insert (m_lastAllocatedConfigurationIndex);
        }
      else
        {
          // look for released ones
          for (uint16_t srcCi = g_srsCiLow[m_srsCurrentPeriodicityId]; srcCi < g_srsCiHigh[m_srsCurrentPeriodicityId]; srcCi++) 
            {
              std::set<uint16_t>::iterator it = m_ueSrsConfigurationIndexSet.find (srcCi);
              if (it==m_ueSrsConfigurationIndexSet.end ())
                {
                  m_lastAllocatedConfigurationIndex = srcCi;
                  m_ueSrsConfigurationIndexSet.insert (srcCi);
                  break;
                }
            }
        } 
    }
  return m_lastAllocatedConfigurationIndex;
  
}


void
LteEnbRrc::RemoveSrsConfigurationIndex (uint16_t srcCi)
{
  NS_LOG_FUNCTION (this << srcCi);
  std::set<uint16_t>::iterator it = m_ueSrsConfigurationIndexSet.find (srcCi);
  NS_ASSERT_MSG (it != m_ueSrsConfigurationIndexSet.end (), "request to remove unkwown SRS CI " << srcCi);
  m_ueSrsConfigurationIndexSet.erase (it);
}

uint8_t 
LteEnbRrc::GetLogicalChannelGroup (EpsBearer bearer)
{
  if (bearer.IsGbr ())
    {
      return 1;
    }
  else
    {
      return 2;
    }
}

uint8_t 
LteEnbRrc::GetLogicalChannelPriority (EpsBearer bearer)
{
  return bearer.qci;
}

void
LteEnbRrc::SendSystemInformation ()
{
  // NS_LOG_FUNCTION (this);

  /*
   * For simplicity, we use the same periodicity for all SIBs. Note that in real
   * systems the periodicy of each SIBs could be different.
   */
  LteRrcSap::SystemInformation si;
  si.haveSib2 = true;
  si.sib2.freqInfo.ulCarrierFreq = m_ulEarfcn;
  si.sib2.freqInfo.ulBandwidth = m_ulBandwidth;

  LteEnbCmacSapProvider::RachConfig rc = m_cmacSapProvider->GetRachConfig ();
  LteRrcSap::RachConfigCommon rachConfigCommon;
  rachConfigCommon.preambleInfo.numberOfRaPreambles = rc.numberOfRaPreambles;
  rachConfigCommon.raSupervisionInfo.preambleTransMax = rc.preambleTransMax;
  rachConfigCommon.raSupervisionInfo.raResponseWindowSize = rc.raResponseWindowSize;
  si.sib2.radioResourceConfigCommon.rachConfigCommon = rachConfigCommon;

  m_rrcSapUser->SendSystemInformation (si);
  Simulator::Schedule (m_systemInformationPeriodicity, &LteEnbRrc::SendSystemInformation, this);
}


} // namespace ns3