#include "delay-jitter-estimation.h"
#include "ns3/tag.h"
#include "ns3/simulator.h"
#include "ns3/string.h"
namespace ns3 {
class DelayJitterEstimationTimestampTag : public Tag
{
public:
DelayJitterEstimationTimestampTag ();
static TypeId GetTypeId (void);
virtual TypeId GetInstanceTypeId (void) const;
virtual uint32_t GetSerializedSize (void) const;
virtual void Serialize (TagBuffer i) const;
virtual void Deserialize (TagBuffer i);
virtual void Print (std::ostream &os) const;
Time GetTxTime (void) const;
private:
uint64_t m_creationTime;
};
DelayJitterEstimationTimestampTag::DelayJitterEstimationTimestampTag ()
: m_creationTime (Simulator::Now ().GetTimeStep ())
{}
TypeId
DelayJitterEstimationTimestampTag::GetTypeId (void)
{
static TypeId tid = TypeId ("anon::DelayJitterEstimationTimestampTag")
.SetParent<Tag> ()
.AddConstructor<DelayJitterEstimationTimestampTag> ()
.AddAttribute ("CreationTime",
"The time at which the timestamp was created",
StringValue ("0.0s"),
MakeTimeAccessor (&DelayJitterEstimationTimestampTag::GetTxTime),
MakeTimeChecker ())
;
return tid;
}
TypeId
DelayJitterEstimationTimestampTag::GetInstanceTypeId (void) const
{
return GetTypeId ();
}
uint32_t
DelayJitterEstimationTimestampTag::GetSerializedSize (void) const
{
return 8;
}
void
DelayJitterEstimationTimestampTag::Serialize (TagBuffer i) const
{
i.WriteU64 (m_creationTime);
}
void
DelayJitterEstimationTimestampTag::Deserialize (TagBuffer i)
{
m_creationTime = i.ReadU64 ();
}
void
DelayJitterEstimationTimestampTag::Print (std::ostream &os) const
{
os << "CreationTime=" << m_creationTime;
}
Time
DelayJitterEstimationTimestampTag::GetTxTime (void) const
{
return TimeStep (m_creationTime);
}
DelayJitterEstimation::DelayJitterEstimation ()
: m_previousRx (Simulator::Now ()),
m_previousRxTx (Simulator::Now ()),
m_jitter (Seconds (0.0)),
m_delay (Seconds (0.0))
{}
void
DelayJitterEstimation::PrepareTx (Ptr<const Packet> packet)
{
DelayJitterEstimationTimestampTag tag;
packet->AddTag (tag);
}
void
DelayJitterEstimation::RecordRx (Ptr<const Packet> packet)
{
DelayJitterEstimationTimestampTag tag;
bool found;
found = packet->FindFirstMatchingTag (tag);
if (!found)
{
return;
}
tag.GetTxTime ();
Time delta = (Simulator::Now () - m_previousRx) - (tag.GetTxTime () - m_previousRxTx);
m_jitter += (Abs (delta) - m_jitter ) / Scalar (16.0);
m_previousRx = Simulator::Now ();
m_previousRxTx = tag.GetTxTime ();
m_delay = Simulator::Now () - tag.GetTxTime ();
}
Time
DelayJitterEstimation::GetLastDelay (void) const
{
return m_delay;
}
Time
DelayJitterEstimation::GetLastJitter (void) const
{
return m_jitter;
}
} // namespace ns3