16#include "ns3/simulator.h"
26 : m_maxTxBufferSize(10 * 1024),
33 m_expectedSeqNumber(0)
52 .AddAttribute(
"MaxTxBufferSize",
53 "Maximum Size of the Transmission Buffer (in Bytes)",
57 .AddAttribute(
"ReorderingTimer",
58 "Value of the t-Reordering timer (See section 7.3 of 3GPP TS 36.322)",
63 "EnablePdcpDiscarding",
64 "Whether to use the PDCP discarding, i.e., perform discarding at the moment "
65 "of passing the PDCP SDU to RLC)",
69 .AddAttribute(
"DiscardTimerMs",
70 "Discard timer in milliseconds to be used to discard packets. "
71 "If set to 0 then packet delay budget will be used as the discard "
72 "timer value, otherwise it will be used this value.",
108 headOfLineDelayInMs =
111 NS_LOG_DEBUG(
"head of line delay in MS:" << headOfLineDelayInMs);
112 if (headOfLineDelayInMs > discardTimerMs)
114 NS_LOG_INFO(
"Tx HOL is higher than this packet can allow. RLC SDU discarded");
115 NS_LOG_DEBUG(
"headOfLineDelayInMs = " << headOfLineDelayInMs);
125 p->AddPacketTag(tag);
126 NS_LOG_INFO(
"Adding RLC SDU to Tx Buffer after adding LteRlcSduStatusTag: FULL_SDU");
135 NS_LOG_INFO(
"Tx Buffer is full. RLC SDU discarded");
155 NS_LOG_INFO(
"RLC layer is preparing data for the following Tx opportunity of "
160 if (txOpParams.
bytes <= 2)
163 NS_LOG_INFO(
"TX opportunity too small - Only " << txOpParams.
bytes <<
" bytes");
174 std::vector<Ptr<Packet>> dataField;
189 NS_LOG_LOGIC(
"First SDU size = " << firstSegment->GetSize());
190 NS_LOG_LOGIC(
"Next segment size = " << nextSegmentSize);
196 while (firstSegment && (firstSegment->GetSize() > 0) && (nextSegmentSize > 0))
198 NS_LOG_LOGIC(
"WHILE ( firstSegment && firstSegment->GetSize > 0 && nextSegmentSize > 0 )");
199 NS_LOG_LOGIC(
" firstSegment size = " << firstSegment->GetSize());
201 if ((firstSegment->GetSize() > nextSegmentSize) ||
203 (firstSegment->GetSize() > 2047))
207 uint32_t currSegmentSize = std::min(firstSegment->GetSize(), nextSegmentSize);
209 NS_LOG_LOGIC(
" IF ( firstSegment > nextSegmentSize ||");
214 Ptr<Packet> newSegment = firstSegment->CreateFragment(0, currSegmentSize);
215 NS_LOG_LOGIC(
" newSegment size = " << newSegment->GetSize());
222 firstSegment->RemovePacketTag(oldTag);
223 newSegment->RemovePacketTag(newTag);
236 firstSegment->RemoveAtStart(currSegmentSize);
238 " firstSegment size (after RemoveAtStart) = " << firstSegment->GetSize());
239 if (firstSegment->GetSize() > 0)
241 firstSegment->AddPacketTag(oldTag);
246 NS_LOG_LOGIC(
" TX buffer: Give back the remaining segment");
265 firstSegment =
nullptr;
268 newSegment->AddPacketTag(newTag);
271 dataFieldAddedSize = newSegment->GetSize();
272 dataField.push_back(newSegment);
273 newSegment =
nullptr;
280 nextSegmentSize -= dataFieldAddedSize;
288 else if ((nextSegmentSize - firstSegment->GetSize() <= 2) ||
m_txBuffer.empty())
291 " IF nextSegmentSize - firstSegment->GetSize () <= 2 || txBuffer.size == 0");
293 dataFieldAddedSize = firstSegment->GetSize();
294 dataField.push_back(firstSegment);
295 firstSegment =
nullptr;
302 nextSegmentSize -= dataFieldAddedSize;
310 " First SDU size = " <<
m_txBuffer.begin()->m_pdu->GetSize());
312 NS_LOG_LOGIC(
" Next segment size = " << nextSegmentSize);
321 NS_LOG_LOGIC(
" IF firstSegment < NextSegmentSize && txBuffer.size > 0");
323 dataFieldAddedSize = firstSegment->GetSize();
324 dataField.push_back(firstSegment);
332 nextSegmentSize -= ((nextSegmentId % 2) ? (2) : (1)) + dataFieldAddedSize;
340 " First SDU size = " <<
m_txBuffer.begin()->m_pdu->GetSize());
342 NS_LOG_LOGIC(
" Next segment size = " << nextSegmentSize);
346 firstSegment =
m_txBuffer.begin()->m_pdu->Copy();
347 firstSegmentTime =
m_txBuffer.begin()->m_waitingSince;
358 auto it = dataField.begin();
360 uint8_t framingInfo = 0;
364 NS_ASSERT_MSG((*it)->PeekPacketTag(tag),
"LteRlcSduStatusTag is missing");
365 (*it)->PeekPacketTag(tag);
376 while (it < dataField.end())
378 NS_LOG_LOGIC(
"Adding SDU/segment to packet, length = " << (*it)->GetSize());
380 NS_ASSERT_MSG((*it)->PeekPacketTag(tag),
"LteRlcSduStatusTag is missing");
381 (*it)->RemovePacketTag(tag);
382 if (packet->GetSize() > 0)
384 packet->AddAtEnd(*it);
408 packet->AddHeader(rlcHeader);
420 params.layer = txOpParams.
layer;
421 params.harqProcessId = txOpParams.
harqId;
500 rxPduParams.
p =
nullptr;
534 NS_LOG_LOGIC(
"VR(UR) is outside the reordering window");
555 newVrUr = (it->first) + 1;
620 NS_LOG_LOGIC(seqNumber <<
" is INSIDE the reordering window");
625 NS_LOG_LOGIC(seqNumber <<
" is OUTSIDE the reordering window");
634 packet->RemoveHeader(rlcHeader);
641 expectedSnLost =
true;
643 <<
". Current SN = " << currSeqNumber);
648 expectedSnLost =
false;
650 <<
". Current SN = " << currSeqNumber);
655 uint8_t extensionBit;
656 uint16_t lengthIndicator;
662 if (extensionBit == 0)
672 if (lengthIndicator >= packet->GetSize())
674 NS_LOG_LOGIC(
"INTERNAL ERROR: Not enough data in the packet ("
675 << packet->GetSize() <<
"). Needed LI=" << lengthIndicator);
679 Ptr<Packet> data_field = packet->CreateFragment(0, lengthIndicator);
680 packet->RemoveAtStart(lengthIndicator);
684 }
while (extensionBit == 1);
701 NS_LOG_LOGIC(
"Framing Info = " << (uint16_t)framingInfo);
800 "INTERNAL ERROR: Transition not possible. FI = " << (
uint32_t)framingInfo);
872 "INTERNAL ERROR: Transition not possible. FI = " << (
uint32_t)framingInfo);
980 "INTERNAL ERROR: Transition not possible. FI = " << (
uint32_t)framingInfo);
1098 "INTERNAL ERROR: Transition not possible. FI = " << (
uint32_t)framingInfo);
1132 NS_LOG_LOGIC(
"(SN = " << it->first <<
") is inside the reordering window");
1139 NS_LOG_LOGIC(
"Reassemble SN between " << lowSeqNumber <<
" and " << highSeqNumber);
1144 while (reassembleSn < highSeqNumber)
void Cancel()
This method is syntactic sugar for the ns3::Simulator::Cancel method.
bool IsPending() const
This method is syntactic sugar for !IsExpired().
virtual void TransmitPdu(TransmitPduParameters params)=0
send an RLC PDU to the MAC for transmission.
virtual void ReportBufferStatus(ReportBufferStatusParameters params)=0
Report the RLC buffer status to the MAC.
This abstract base class defines the API to interact with the Radio Link Control (LTE_RLC) in LTE,...
LteRlcSapUser * m_rlcSapUser
RLC SAP user.
TracedCallback< Ptr< const Packet > > m_txDropTrace
The trace source fired when the RLC drops a packet before transmission.
TracedCallback< uint16_t, uint8_t, uint32_t, uint64_t > m_rxPdu
Used to inform of a PDU reception from the MAC SAP user.
void DoDispose() override
Destructor implementation.
LteMacSapProvider * m_macSapProvider
MAC SAP provider.
uint16_t m_packetDelayBudgetMs
the packet delay budget in ms of the corresponding logical channel
TracedCallback< uint16_t, uint8_t, uint32_t > m_txPdu
Used to inform of a PDU delivery to the MAC SAP provider.
virtual void ReceivePdcpPdu(Ptr< Packet > p)=0
Called by the RLC entity to notify the PDCP entity of the reception of a new PDCP PDU.
This class implements a tag that carries the status of a RLC SDU for the fragmentation process Status...
uint8_t GetStatus() const
Get status function.
void SetStatus(uint8_t status)
Set status function.
LTE RLC Unacknowledged Mode (UM), see 3GPP TS 36.322.
SequenceNumber10 m_vrUr
VR(UR)
Ptr< Packet > m_keepS0
keep S0
void ReassembleAndDeliver(Ptr< Packet > packet)
Reassemble and deliver function.
void DoReportBufferStatus()
Report buffer status.
uint32_t m_txBufferSize
transmit buffer size
static TypeId GetTypeId()
Get the type ID.
void ReassembleOutsideWindow()
Reassemble outside window.
void DoDispose() override
Destructor implementation.
void ExpireReorderingTimer()
Expire reordering timer.
Time m_reorderingTimerValue
Timers.
SequenceNumber10 m_expectedSeqNumber
Expected Sequence Number.
ReassemblingState_t m_reassemblingState
reassembling state
void ReassembleSnInterval(SequenceNumber10 lowSeqNumber, SequenceNumber10 highSeqNumber)
Reassemble SN interval function.
void ExpireRbsTimer()
Expire RBS timer.
EventId m_rbsTimer
RBS timer.
void DoNotifyTxOpportunity(LteMacSapUser::TxOpportunityParameters txOpParams) override
MAC SAP.
SequenceNumber10 m_vrUx
VR(UX)
uint16_t m_windowSize
Constants.
std::map< uint16_t, Ptr< Packet > > m_rxBuffer
Reception buffer.
uint32_t m_discardTimerMs
the discard timer value in milliseconds
void DoNotifyHarqDeliveryFailure() override
Notify HARQ delivery failure.
SequenceNumber10 m_vrUh
VR(UH)
void DoTransmitPdcpPdu(Ptr< Packet > p) override
RLC SAP.
void DoReceivePdu(LteMacSapUser::ReceivePduParameters rxPduParams) override
Receive PDU function.
uint32_t m_maxTxBufferSize
maximum transmit buffer status
std::deque< TxPdu > m_txBuffer
Transmission buffer.
std::list< Ptr< Packet > > m_sdusBuffer
List of SDUs in a packet.
EventId m_reorderingTimer
reordering timer
bool IsInsideReorderingWindow(SequenceNumber10 seqNumber)
Is inside reordering window function.
SequenceNumber10 m_sequenceNumber
State variables.
bool m_enablePdcpDiscarding
whether to use the PDCP discarding (perform discarding at the moment of passing the PDCP SDU to RLC)
void AddAtEnd(Ptr< const Packet > packet)
Concatenate the input packet at the end of the current packet.
uint32_t GetSize() const
Returns the the size in bytes of the packet (including the zero-filled initial payload).
bool FindFirstMatchingByteTag(Tag &tag) const
Finds the first tag matching the parameter Tag type.
uint32_t PeekHeader(Header &header) const
Deserialize but does not remove the header from the internal buffer.
Smart pointer class similar to boost::intrusive_ptr.
Tag to calculate the per-PDU delay from eNb RLC to UE RLC.
Time GetSenderTimestamp() const
Get the instant when the RLC delivers the PDU to the MAC SAP provider.
uint16_t GetValue() const
Extracts the numeric value of the sequence number.
void SetModulusBase(SequenceNumber10 modulusBase)
Set modulus base.
static EventId Schedule(const Time &delay, FUNC f, Ts &&... args)
Schedule an event to expire after delay.
static Time Now()
Return the current simulation virtual time.
Simulation virtual time values and global simulation resolution.
int64_t GetNanoSeconds() const
Get an approximation of the time stored in this instance in the indicated unit.
int64_t GetMilliSeconds() const
Get an approximation of the time stored in this instance in the indicated unit.
a unique identifier for an interface.
TypeId SetParent(TypeId tid)
Set the parent TypeId.
Hold an unsigned integer type.
#define NS_ASSERT_MSG(condition, message)
At runtime, in debugging builds, if this condition is not true, the program prints the message to out...
#define NS_LOG_COMPONENT_DEFINE(name)
Define a Log component with a specific name.
#define NS_LOG_DEBUG(msg)
Use NS_LOG to output a message of level LOG_DEBUG.
#define NS_LOG_LOGIC(msg)
Use NS_LOG to output a message of level LOG_LOGIC.
#define NS_LOG_FUNCTION(parameters)
If log level LOG_FUNCTION is enabled, this macro will output all input parameters separated by ",...
#define NS_LOG_INFO(msg)
Use NS_LOG to output a message of level LOG_INFO.
#define NS_OBJECT_ENSURE_REGISTERED(type)
Register an Object subclass with the TypeId system.
Ptr< T > Create(Ts &&... args)
Create class instances by constructors with varying numbers of arguments and return them by Ptr.
Time MilliSeconds(uint64_t value)
Construct a Time in the indicated unit.
Every class exported by the ns3 library is enclosed in the ns3 namespace.
Ptr< const AttributeChecker > MakeBooleanChecker()
Ptr< const AttributeChecker > MakeUintegerChecker()
Ptr< const AttributeAccessor > MakeTimeAccessor(T1 a1)
Ptr< const AttributeAccessor > MakeUintegerAccessor(T1 a1)
Ptr< const AttributeAccessor > MakeBooleanAccessor(T1 a1)
Ptr< const AttributeChecker > MakeTimeChecker()
Helper to make an unbounded Time checker.
Parameters for LteMacSapProvider::ReportBufferStatus.
uint32_t txQueueSize
the current size of the RLC transmission queue
uint16_t retxQueueHolDelay
the Head Of Line delay of the retransmission queue
uint16_t txQueueHolDelay
the Head Of Line delay of the transmission queue
uint32_t retxQueueSize
the current size of the RLC retransmission queue in bytes
uint8_t lcid
the logical channel id corresponding to the sending RLC instance
uint16_t rnti
the C-RNTI identifying the UE
uint16_t statusPduSize
the current size of the pending STATUS RLC PDU message in bytes
Parameters for LteMacSapProvider::TransmitPdu.
Parameters for LteMacSapUser::ReceivePdu.
Ptr< Packet > p
the RLC PDU to be received
Parameters for LteMacSapUser::NotifyTxOpportunity.
uint8_t harqId
the HARQ ID
uint32_t bytes
the number of bytes to transmit
uint8_t componentCarrierId
the component carrier id
uint8_t layer
the layer of transmission (MIMO)
Store an incoming (from layer above us) PDU, waiting to transmit it.