A Discrete-Event Network Simulator
API
rtt-estimator.h
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1/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2//
3// Copyright (c) 2006 Georgia Tech Research Corporation
4//
5// This program is free software; you can redistribute it and/or modify
6// it under the terms of the GNU General Public License version 2 as
7// published by the Free Software Foundation;
8//
9// This program is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12// GNU General Public License for more details.
13//
14// You should have received a copy of the GNU General Public License
15// along with this program; if not, write to the Free Software
16// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17//
18// Author: Rajib Bhattacharjea<raj.b@gatech.edu>
19//
20
21// Georgia Tech Network Simulator - Round Trip Time Estimation Class
22// George F. Riley. Georgia Tech, Spring 2002
23
24
25#ifndef RTT_ESTIMATOR_H
26#define RTT_ESTIMATOR_H
27
28#include "ns3/nstime.h"
29#include "ns3/object.h"
30
31namespace ns3 {
32
43class RttEstimator : public Object {
44public:
49 static TypeId GetTypeId (void);
50
56 RttEstimator (const RttEstimator& r);
57
58 virtual ~RttEstimator();
59
60 virtual TypeId GetInstanceTypeId (void) const;
61
66 virtual void Measurement (Time t) = 0;
67
72 virtual Ptr<RttEstimator> Copy () const = 0;
73
77 virtual void Reset ();
78
83 Time GetEstimate (void) const;
84
93 Time GetVariation (void) const;
94
99 uint32_t GetNSamples (void) const;
100
101private:
103
104protected:
108};
109
124public:
129 static TypeId GetTypeId (void);
130
132
138
139 virtual TypeId GetInstanceTypeId (void) const;
140
145 void Measurement (Time measure);
146
147 Ptr<RttEstimator> Copy () const;
148
152 void Reset ();
153
154private:
165 uint32_t CheckForReciprocalPowerOfTwo (double val) const;
175 void IntegerUpdate (Time m, uint32_t rttShift, uint32_t variationShift);
183 void FloatingPointUpdate (Time m);
184 double m_alpha;
185 double m_beta;
186
187};
188
189} // namespace ns3
190
191#endif /* RTT_ESTIMATOR_H */
A base class which provides memory management and object aggregation.
Definition: object.h:88
Smart pointer class similar to boost::intrusive_ptr.
Definition: ptr.h:74
Base class for all RTT Estimators.
Definition: rtt-estimator.h:43
Time m_initialEstimatedRtt
Initial RTT estimation.
virtual TypeId GetInstanceTypeId(void) const
Get the most derived TypeId for this Object.
Time GetEstimate(void) const
gets the RTT estimate.
virtual void Reset()
Resets the estimation to its initial state.
Time m_estimatedVariation
Current estimate variation.
uint32_t m_nSamples
Number of samples.
uint32_t GetNSamples(void) const
gets the number of samples used in the estimates
Time GetVariation(void) const
Note that this is not a formal statistical variance; it has the the same units as the estimate.
virtual ~RttEstimator()
Time m_estimatedRtt
Current estimate.
static TypeId GetTypeId(void)
Get the type ID.
virtual Ptr< RttEstimator > Copy() const =0
Copy object (including current internal state)
virtual void Measurement(Time t)=0
Add a new measurement to the estimator.
The "Mean--Deviation" RTT estimator, as discussed by Van Jacobson.
static TypeId GetTypeId(void)
Get the type ID.
double m_beta
Filter gain for variation.
void Measurement(Time measure)
Add a new measurement to the estimator.
void Reset()
Resets the estimator.
void FloatingPointUpdate(Time m)
Method to update the rtt and variation estimates using floating point arithmetic, used when the value...
Ptr< RttEstimator > Copy() const
Copy object (including current internal state)
uint32_t CheckForReciprocalPowerOfTwo(double val) const
Utility function to check for possible conversion of a double value (0 < value < 1) to a reciprocal p...
double m_alpha
Filter gain for average.
virtual TypeId GetInstanceTypeId(void) const
Get the most derived TypeId for this Object.
void IntegerUpdate(Time m, uint32_t rttShift, uint32_t variationShift)
Method to update the rtt and variation estimates using integer arithmetic, used when the values of Al...
Simulation virtual time values and global simulation resolution.
Definition: nstime.h:103
a unique identifier for an interface.
Definition: type-id.h:59
Every class exported by the ns3 library is enclosed in the ns3 namespace.