In the last free years, there has been important growth in wireless communications. The Quality of Service has become an important consideration that supports many applications that utilize the resources of a network. Some applications are the Voice over IP and the multimedia services such as video streaming. WiMAX network is a new standard network which takes into consideration the quality of service. This project refers to the measurement of network Quality of Service (QoS) parameters of various real time applications like VoIP and video streaming.
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1
Quality of Service Seeker
By
Khaled Houssein
Wisam Salhab
A report submitted to the Department of Electrical Engineering in partial fulfillment of the
requirements for the degree of Master of Science in Electrical Engineering
This is to certify that I have examined this copy of Master’s report by
Khaled Houssein
Wisam Salhab
And have found that it is complete and satisfactory in all the respects,
And that any and all revisions required by the final
Examining committee has been made.
COMMITTEE MEMBERS:
Approved:
Jihad Daba, Ph.D.
Supervisor
Approved:
Rafic Ayoubi, Ph.D.
First Moderator
Approved:
Issam Dagher, Ph.D.
Second Moderator
Date of report defense: January 12, 2013
3
ACKNOWLEDGEMENTS
This report could not have been written if it were not for the contribution and
encouragement of various people and organizations.
The authors’ first wish is to thank the project supervisor, Dr. Jihad Daba for his advice and
support. Special gratitude goes to project moderators, Dr. Rafic Ayoubi and Dr. Issam Dagher.
This report would not have been written without the perseverance of the authors, and the
restless nights spent to finalize the project. Also, the encouragement and devotion of family and
friends should be mentioned who have helped a great deed.
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ABSTRACT
In the last free years, there has been important growth in wireless communications. The
Quality of Service has become an important consideration that supports many applications that
utilize the resources of a network. Some applications are the Voice over IP and the multimedia
services such as video streaming. WiMAX network is a new standard network which takes into
consideration the quality of service. This project refers to the measurement of network Quality of
Service (QoS) parameters of various real time applications like VoIP and video streaming.
The first phase of this project is the QoS parameter measurements. In this phase, a set of
QoS parameters are defined. These parameters are delay, delay variation (jitter) and packet loss
probability . They are used in the development of program. Then the “QoS Seeker application”
developed in this project is presented, including its principle . The following contents give a
collection and analysis of results of the measurements of QoS parameters using the “QoS Seeker
program”.
The second phase is the video streaming and VoIP call simulation. In this part, elements
of general video and VoIP applications are introduced. The parameters that specify the quality
of service of the network , such as, throughput, packet loss, jitter and latency , are analyzed for
different times of services
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Table of Contents
TABLE OF CONTENTS ............................................................................................................................................ 5
OVERVIEW OVER WIMAX .................................................................................................................................. 12
2.2.3. Jitter or PDV ..................................................................................................................................... 29
2.2.4. Packet Loss ........................................................................................................................................ 29
2.3. APPLICATIONS FOR QUALITY OF SERVICE ................................................................... 30
3.1.2. VoIP Network Connections ..................................................................................................................... 32
3.1.3. Real Time Protocol ................................................................................................................................ 34
A. G.729 Codec ............................................................................................................................................................... 35
B. G.711 Codec ............................................................................................................................................................... 35
3.1.5. VoIP QoS ............................................................................................................................................... 36
3.2. IP MEDIA SUBSYSTEM SERVICES - IMS ......................................................................... 37
3.2.1. Video Streaming ...................................................................................................................................... 37
Latency or Average Delay ......................................................................................................................................... 47
Jitter or Delay Variation ........................................................................................................................................... 48
Packet Loss ................................................................................................................................................................. 49
Mean Opinion Score (MOS) ............................................................................................................................................ 49
4.4.3. Updating the Map ................................................................................................................................... 52
WCF Service .............................................................................................................................................................. 53
5.1. TEST FOR STATIC WIMAX USER .................................................................................... 57
5.1.1. Results for VOIP traffic using G.711 codec ........................................................................................... 57
A. Bandwidth Availability ........................................................................................................................................... 57
B. Jitter Performance ................................................................................................................................................... 59
C. Latency Performance .............................................................................................................................................. 61
D. Packet Loss Performance ........................................................................................................................................ 62
E. Overall VoIP performance (MOS value) ................................................................................................................ 63
5.1.2. RESULTS FOR VIDEO STREAMING ................................................................................ 64
A. Bandwidth Availability ........................................................................................................................................... 64
B. Jitter Performance ................................................................................................................................................... 67
C. Latency Performance .............................................................................................................................................. 68
D. Packet Loss Performance ........................................................................................................................................ 69
8
5.2. TEST FOR MOBILE WIMAX USER .................................................................................... 70
5.2.1. Results for VOIP traffic using G.711 codec ............................................................................................ 70
A. Bandwidth Availability ........................................................................................................................................... 70
B. Jitter Performance ....................................................................................................................................... 72
C. Latency Performance .................................................................................................................................. 73
D. Packet Loss Performance ........................................................................................................................... 74
E. Overall VoIP performance (MOS value) .................................................................................................... 74
6.2. FUTURE WORK ................................................................................................................. 77
LIST OF REFERENCES .......................................................................................................................................... 78
EQUIPMENTS USED ............................................................................................................................................... 80
APPENDIX A2............................................................................................ ERROR! BOOKMARK NOT DEFINED.
PROJECT CODES ..................................................................................... ERROR! BOOKMARK NOT DEFINED.
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LIST OF TABLES
TABLE 1 : WIMAX VS. WI-FI ....................................................................................................................................... 27
FIGURE 6 : HOW ICI IS FOUND ....................................................................................................................................... 16
FIGURE 7 : OFDM SYMBOL USERS .............................................................................................................................. 17
FIGURE 8 : NETWORK ARCHITECTURE OF WIMAX ...................................................................................................... 18
FIGURE 9 : PHYSICAL LAYERS OF WIMAX ................................................................................................................... 20
FIGURE 10 : BLOCK DIAGRAM OF WIMAX TRANSMITTER ............................................................................................ 23
FIGURE 11 : BLOCK DIAGRAM OF WIMAX RECEIVER .................................................................................................. 23
FIGURE 18 : RTP DATAGRAM FOR VOIP ...................................................................................................................... 34
FIGURE 24 : MAIN FORM OF QOS SEEKER APPLICATION .............................................................................................. 41
FIGURE 25 : VOIP MAP FORM ...................................................................................................................................... 43
FIGURE 26 : GETTING THE USER GPS LOCATION STEP ................................................................................................. 46
FIGURE 27 : LATENCY IN NETWORK ............................................................................................................................. 47
FIGURE 28 : R-FACTOR RATING WITH MOS SCORE MAPPING AND USER SATISFACTION LEVEL ..................................... 51
FIGURE 30 : EL MINA MAP ........................................................................................................................................... 54
FIGURE 32 : VOIP DOWNLOAD RATES PLOT ................................................................................................................. 58
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FIGURE 33 : VOIP UPLOAD RATES PLOT ...................................................................................................................... 59
FIGURE 34 : VOIP MEASURED JITTER ........................................................................................................................... 60
FIGURE 35 : VOIP MEASURED LATENCY ...................................................................................................................... 61
FIGURE 36 : VOIP MEASURED PACKET LOSS ............................................................................................................... 62
FIGURE 37 : MOS VALUES PLOT .................................................................................................................................. 63
FIGURE 38 : VIDEO STREAMING DOWNLOADS RATES PLOT.......................................................................................... 65
FIGURE 39 : VIDEO STREAMING UPLOADS RATES PLOT ............................................................................................... 66
FIGURE 40 : MEASURED JITTER VIDEO STREAMING ..................................................................................................... 67
FIGURE 41 : MEASURED LATENCY VIDEO STREAMING ................................................................................................ 68
FIGURE 42 : PACKET LOSS VIDEO STREAMING ............................................................................................................. 69
FIGURE 43 : MOBILE DOWNLOAD RATES PLOT .............................................................................................................. 71
FIGURE 44 : MOBILE UPLOAD RATES PLOT .................................................................................................................... 71
FIGURE 45 : MEASURED MOBILE JITTER ....................................................................................................................... 72
FIGURE 46 : MEASURED MOBILE LATENCY .................................................................................................................. 73
FIGURE 47 : MEASURED MOBILE PACKET LOSS ............................................................................................................ 74
FIGURE 48 : MOBILE MOS VALUES ............................................................................................................................... 75
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Chapter 1
Overview over WiMAX
1.1. Introduction
WiMAX stands for Worldwide Interoperability for Microwave Access, joins the
technology of Wi-Fi and high rate internet to offer high-speed internet across long distances. It
can be used as a substitute to the current cabled access networks such as optical fibers and
Digital Subscriber lines (DSL). Also it provides broadband services for people who can’t manage
wired broadband services. It satisfies different types of access, such as fixed, portable and mobile
access. In order to use these types, two versions are presented, the IEEE802.16d which known as
Fixed WiMAX and IEEE802.16e that is known as Mobile WiMAX. WiMAX radio could be able
to service data rates up to 70 Mbps and operating channel bandwidth from 1.25 MHZ up to 20
MHZ. It should also support access to a distance of 50 km between base station and the user.
WiMAX sustains Non Line of Sight (NLOS) communication. The frequency bands that operate
for WiMAX are 2.5GHz, 3.5 GHz and 5.8 GHz. WiMAX can be used for various applications
such as broadband connections, hotspots and high speed connectivity. The WiMAX base station
covers 5 to 10 km range.
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Figure 1 : WiMAX standards
1.2. Fixed WiMAX (IEEE802.16d)
It is used to optimize for fixed access and based on orthogonal frequency division
multiplexing (OFDM). Also, it is designed to operate in a range of 10 to 66 GHz spectrum and
gives the specifications of physical layer (PHY) and medium access control (MAC) of the air
interference systems. The transmission line needed is NLOS with the base station. It is found for
the broadband wireless access at high speed and it is easily installed. The features of
IEEE802.16d are:
Non Line of sight service
Multiple radio modulation options
Quality of service features
14
Figure 2 : Fixed WiMAX Architecture 1.3. Mobile WiMAX (IEEE802.16e)
It is used to optimize for mobile access and based on scalable orthogonal frequency
division multiple accesses. It delivers the broadband data to a moving terminal such as laptops
with integrated WiMAX modem.
15
Figure 3: 802.16 standards
Figure 4 : Mobile WiMAX Architecture
1.4. Orthogonal Frequency Division Multiplexing (OFDM)
The Orthogonal Frequency Division Multiplexing is used to provide the operator to
overcome the Inter-Symbol interference (ISI) by the channel and the difficulties of Non-Line-of-
16
Sight (NLOS) transmitting in a better effective approach. The ISI happens when the delay spread
of channel is greater than the symbol time.
Figure 5: OFDM Architecture
Because of that OFDM divides the data into parallel paths and each one has a multiple
separate carrier with low rate. Then, signals are sent by different frequencies to each user with a
various number of cycles in a symbol period, and data is carried by varying the phase of each
4.1. EastLongitude: is the East Longitude of the Map.
4.2. WestLongitude: is the West Longitude of the Map.
4.3. SouthLatitude: is the south Latitude of the Map.
The figure below shows the step on QoS Seeker when updating the map:
Figure 26 : Updated Map
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Chapter 5
Implementation results
To analyze the quality of service in WiMAX network, various real life use cases are
considered. WiMAX affords basic IP connectivity. VOIP is the first application tested. With the
availability of a larger data channels, another familiar application these days is viewing videos
over the internet. So video streaming is analyzed as well. In this chapter, the implementation
results are presented. The QoS parameters obtained for VOIP traffic is presented first. The video
streaming traffic results follow.
5.1. Test for Static WiMAX user
We test the QoS Seeker from many places in El Mina. The time is every one minute for
20 minutes of testing.
5.1.1. Results for VOIP traffic using G.711 codec
In the first case the VOIP traffic is tested with codec G.711. Figure 30 to Figure 35 displays
the variation of throughput, percentage packet loss, average jitter, and average delay measured
along with the QoS Seeker for 20 min and the calculated MOS values.
A. Bandwidth Availability
This table shows the Bandwidth tests in Kb/s for 20 min during VoIP Call.
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Time
(min)
Download
(Kbps)
Upload
(Kbps)
Time
(min)
Download
(Kbps)
Upload
(Kbps)
1 4 40 11 72 8
2 70 20 12 72 24
3 78 36 13 92 36
4 90 8 14 82 36
5 68 30 15 86 34
6 74 6 16 74 18
7 86 14 17 64 38
8 94 42 18 82 18
9 110 10 19 114 60
10 76 56 20 94 8 Table 7 : Download and Upload rates for VoIP
Figure 27 : VoIP Download rates Plot
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Figure 28 : VoIP Upload Rates Plot
The maximum bandwidth available was 114Kb/s and the minimum was 4kb/s. the
average is around 79 Kb/s. the maximum value is obviously a very good measure for VoIP
deployment. If we ignore it, the minimum value is not enough to guarantee a good VoIP
implementation. Although the bandwidth requirement is not the most important issue in ensuring
a good QoS in VoIP application , the greater the connection speed does imply the better voice
quality that we can get.
B. Jitter Performance
The figure below shows the jitter values obtained during 20 minutes of measurements.
These values are measured for a period of 1 min in each VoIP session. The minimum value was
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around 10 ms at time t=9 minute while the maximum value was around 110 ms at time t =2 min.
the measurements were fluctuated quite obviously.
Figure 29 : VoIP Measured Jitter
We can divide the standard of good jitter level into four categories:
- 0-30ms: Excellent
- 30-40ms : Very good
- 40-50ms : Good
- 50-60 ms : Fair
- Otherwise : Poor
Jitter is an issue that only occurred in packet-based network and cannot be avoided. It
happens because the packets that are sent one by one arrive out of sequence and time because of
travelling. The jitter will get worst in a congested network. To deal with this problem and to
minimize the value of jitter itself, a network with uncongested network and high bandwidth
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availability is definitely most desirable. In this test we can see that the bandwidth availability for
WiMAX network is sometimes good and other times is not.
Generally, a direct correlation between bandwidth and jitter recommended that the highest
bandwidth available should generate the smallest jitter value. However, this is test showed that it
was not necessarily happened like that. For example the jitter value 110 ms was the biggest at
t=2 min but the bandwidth measured on that time was not the lowest, measured 70 Kb/s. Like so,
the smallest jitter was 10 ms at t=9 min but the bandwidth measured was 110 Kb/s, which is not
the Highest measured value.
All of these results showed that the QoS elements of bandwidth for this network did not
really affect the jitter occurred during the VoIP call.
C. Latency Performance
The ITU-T recommendation for a good quality voice is for the latency to be less than 150
ms. the figure below shows the latency measured during the test of the QoS Seeker.
Figure 30 : VoIP Measured Latency
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According to the Standard Quality Management (SQM) scale, we can divide the latency into:
- 0-50ms : good
- 50-300ms : acceptable
- from Otherwise : poor
From the figure above, the biggest latency value was 290 ms at t=14 min while the smallest
latency was 140 ms at t= 1min, averaging for this network around 213 ms. Comparing these
latency with the Standard Quality Management scale , we can see that these levels of latency
were good.
D. Packet Loss Performance
Figure 31 : VoIP Measured Packet Loss
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We can see that the packet loss values varied between 5% and 34% during the 20 min of
video call. This of course affects the voice quality status which differs between poor, good, and
very good quality. When the packet loss is high the voice was not completely clear.
E. Overall VoIP performance (MOS value)
The overall performance of this VoIP Call or of VoIP in general can be evaluated using Mean
Opinion Score (MOS) values. The calculated MOS values are stated in the figure below.
Figure 32 : MOS values Plot
These values are calculated using the equations mentioned in section 4.4.2. The values
varied between 3.5 and 4.4, averaging around 3.94. According to Figure 26 and table, these
values are rated as just perceptible but not annoying. From this result we can conclude that
although the latency and jitter measured were good some time, there are other factor that
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contribute to the all performance of VoIP in a network which is the packet loss. These factors
have to be as loss as possible in order to set a good quality of VoIP Service.
5.1.2. Results for Video Streaming
There are several proposed video quality factors that affects quality of video streaming.
The Video Quality Metric (VQM) is a very important factor that has been accepted as ANSI
standard T1.801.03. VQM is based on comparison of the original and degraded video. We did
not use it because of its high computational complexity and requirement for high-end hardware,
as well as communication overhead.
For video streaming, the bandwidth and the jitter play important roles in the quality of
video. The average delay is not very important, because users tolerate some startup delay.
Bandwidth is the main factor influencing whether a video of the desired quality. As video frames
are transmitted in packets over the network, lost or delayed packets may cause frame drops at the
user. Low jitter is a requirement for a smooth streaming experience. Inter-frame jitter is easily
perceptible by the user.
While testing the video streaming performance, we played a video on you tube.com with
35 min of length and we run the QoS Seeker application. WiMAX supports both live and on-
demand streaming. In this Project, we focus only on on-demand streaming.
Figure 36 to Figure 40 displays the variation of throughput, percentage packet loss, average
jitter, and average delay measured along with the QoS Seeker for 20 min.
A. Bandwidth Availability
This table shows the Bandwidth tests in Kb/s for 20 min during VoIP Call.
65
Time
(min)
Download
(Kbps)
Upload
(Kbps)
Time
(min)
Download
(Kbps)
Upload
(Kbps)
1 71 6 11 68 7
2 62 8 12 79 7
3 102 7 13 69 6
4 68 6 14 69 6
5 70 5 15 70 9
6 31 6 16 78 6
7 62 5 17 66 6
8 52 7 18 70 6
9 75 12 19 84 7
10 56 6 20 71 6
Table 8 : Video Streaming Downloads and Uploads rates
Figure 33 : Video Streaming Downloads rates Plot
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Figure 34 : Video Streaming Uploads rates Plot
Ignoring the maximum value of bandwidth 102 kbps that is obviously a good measure for
video streaming deployment, the minimum value alone is not good enough to guarantee a good
quality but the average bandwidth which is around 69 kbps still a good measured value to deliver
a good video streaming. The Streaming-Video is typically unidirectional that means that the
upload link is not used. Therefore the upload has low values.
Since the bandwidth requirement is the most important issue in ensuring a good QoS in
video streaming, the greater the connection speed does imply the better quality that we can get.
Our experience talking over during the test showed that we were able to have a smooth video
which noticeable interruptions only in the first 4 minutes.
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B. Jitter Performance
The figure shows the jitter values obtained during 20 minutes of measurements. These
values are measured for a period of 1 min . The minimum value was around 15 ms at time t=14
minute while the maximum value was around 187 ms at time t =10 min.
Figure 35 : Measured Jitter Video Streaming
We adopt the evaluation method of Wang et al. in our study. It proposes a simple quality
classification based on jitter, wherein smooth video has jitter less than 50 ms, rough video has
jitter exceeding 300 ms, and average video has jitter between these two thresholds.
According to this evaluation we can see that the jitter doesn’t exceed the maximum
thresholds which mean that the video streaming was good during the test. we remark that the
jitter value increases with time then it increases after 10 minutes of playing . Then it becomes a
constant value because the video was full buffering.
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C. Latency Performance
Depending on the video application's buffering capabilities, the Latency in video
streaming should be no more than 4 to 5 seconds. the figure below shows the latency measured
during the test of the QoS Seeker.
Figure 36 : Measured Latency Video Streaming
From the figure above, the biggest latency value was 266 ms at t=10 min while the
smallest latency was 64 ms at t= 1min, averaging for this network around 157 ms. Comparing
these latency with the evaluation, we can see that these levels of latency were excellent. The
video suffered frequent stutters and pauses during the first 6 min but then no pauses happened .
these is because the variation of latency values.
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D. Packet Loss Performance
When addressing the QoS needs of Streaming-Video traffic, the Loss should be no more
than 5 percent.
Figure 37 : Packet Loss Video Streaming
Video and audio quality are directly affected by packet loss, since the video streaming
deployment uses multicast over UDP (vs. RTP), which provides no protection from packet loss.
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5.2. Test for Mobile WiMAX User
To analyze the quality of service in mobile WiMAX network, we tested the VoIP
application. The user drove with speed 10km/h that reaches 50 km/h with time .The problem of
mobility is important in wireless network because internet connectivity can only be useful if it’s
available during the movement of node. To enhance mobility, wireless access systems are
designed such as IEEE 802.16e to operate on the move without any interruption of services. In
this section we are analyzing the QoS parameters Throughput, Average Jitter and Average end to
end Delay of a mobile WiMAX network (IEEE 802.16e).
5.2.1. Results for VOIP traffic using G.711 codec
the VOIP traffic is tested with codec G.711. Figure 41 to Figure 46 displays the variation of
throughput, percentage packet loss, average jitter, and average delay measured along with the
QoS Seeker for 5 minutes and the calculated MOS values.
A. Bandwidth Availability
This table shows the Bandwidth tests in Kb/s for 20 min during VoIP Call.
Time
(sec)
Download
(Kbps)
Upload
(Kbps)
30 82 13
60 63 17
90 66 20
120 54 12
150 62 23
180 45 18
210 35 16
240 32 8
270 29 10
300 33 14
Table 9 : Mobile Downloads and Uploads rates
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Figure 38 : mobile download rates plot
Figure 39 : mobile Upload rates plot
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The throughput is varying according to data or packets received and sent by the VoIP application The
variation of throughput with respect to change in speed is shown in the figure 41. The speed is
increasing with time. According to figure 41, at t=30s the speed was 10 km/h (Kilometer per hour)
the throughput was 82 kbps, with the increase in speed the throughput is decreasing. At speed of
50Km/h the throughput is minimum i.e. 29 kbps. As the user moves, it will perform handover and
will go far away from its original registered BS and during that time there is loss of data (bytes and
packets). After that as speed increases the throughput will start increasing again .
B. Jitter Performance
Figure 40 : Measured mobile Jitter
According to figure 43, jitter is very less initially i.e.200 ms when the user is moving with less
speed of 10km/h; with increase in speed, jitter will also increase i.e. 630ms at 50 Km/h speed.
The reason is that data is split up into manageable packets with headers and footers that specify
the correct order of the data packets or whole signal is broken down into portions of data which
73
is transmitted to the receiving unit of El Mina Base station for assembly. If jitter occurs,
synchronization becomes a problem and the receiving unit finds it difficult to correctly assemble
the incoming data stream. Therefore at high speed jitter is more and throughput is less.
C. Latency Performance
The ITU-T recommendation for a good quality voice is for the latency to be less than 150
ms. During transmission, delay is introduced and average end to end delay (Latency) changes
with the change in speed. Variation of Latency with respect to speed in time is shown in figure
44.
Figure 41 : Measured mobile Latency
According to the figure, the average delay is less when speed is less i.e. 280 ms at the
speed of 10 km/h but as speed increases average delay decreases i.e. 712 ms at the speed of 50
km/h. the Average delay increases or decreases according to movement of the user .
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D. Packet Loss Performance
Figure 42 : Measured mobile Packet Loss
As the user moves, the speed increases and the packet loss percentage increases rapidly
i.e. 20% loss at the speed of 10 km/h but as speed increases, loss increases too i.e. 88% loss at
the speed of 45 km/h. In addition a handover problem may occur and during that time there is
loss of data (bytes and packets).
E. Overall VoIP performance (MOS value)
The overall performance of this VoIP Call or of VoIP in general can be evaluated using Mean
Opinion Score (MOS) values. The calculated MOS values are stated in the figure below.
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Figure 43 : mobile MOS values
These values are calculated using the equations mentioned in section 4.4.2. The values
varied between 1.2 and 3.7, averaging around 2.3. According to Figure 46 and table 4, these
values are rated as just Perceptible & slightly annoying and Annoying but not objectionable.
From this result we can conclude that the latency and jitter measured were not good enough to
VoIP call , and the other factor that contribute to the all performance of VoIP in a network which
is the packet loss is very high . These factors have to be as loss as possible in order to set a good
quality of VoIP Service but in this case they are not. These causes a poor VoIP call.
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Chapter 6
Conclusion and Future Work
6.1. Conclusion
In the Project, we developed an application that evaluates the performance of the network
by analyzing the Quality of Service metrics. This application is called “WiMAX Quality of
Service Seeker “or “WiMAX QoS Seeker”. It can provide the user the ability to easily determine
the location of high quality WiMAX connections. The applications QoS Seeker targets are real
time services such as video streaming and Voice over IP.
To achieve its goals the QoS Seeker analyzes the parameters at the end user that may affect the
quality of the service desired. VoIP traffic and video streaming traffic was analyzed using a
simulation based on Matlab Software. The effect of QoS parameters like throughput, packet
loss, average jitter and average delay was studied.
For Fixed WiMAX user, the application works well and he no longer has to guess and/or
randomly move to find a physical position where an applications’ QoS is at an acceptable level.
But here the results of the analysis are not optimal because of the few number of packets sent to
measure the Round Trip Time (RTT).
While for mobile WiMAX user, the application can’t show the best quality of service
results. The speed of the mobile user and his location are the most issues that lead us to wrong
results. For example, A handover may occur while the user is moving which results a bug in the
analysis.
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For the real time simulation, the user should be in El Mina or El Tal where the WiMAX network
covers these two areas .Otherwise it will not work properly.
The IEEE 802.16/WiMAX network architecture was presented and the MAC layer
features that enable end-to-end QoS mechanism in the network were discussed. The general
concepts of Quality of service (QoS) in WiMAX network were studied. Various service flows
that are supported in WiMAX were discussed in details. Related survey was presented in detail
to provide background to the reader.
6.2. Future Work
VOIP traffic and video streaming were the two applications considered in the current
analysis. Further analysis could be done for other applications including, video telephony which
combines video traffic and VOIP traffic, File Transfer Protocol (FTP) traffic etc.
The work showed in this report builds a MOS score calculator based on E-Model method.
This calculator reads the delay and packet loss measured by capturing the RTT of 100 packets.
Possible future work could be integrating the new objective approach with a packet capture tool
like Wireshark to calculate the speech quality during real time packet capture. This would help to
efficiently monitor the speech quality of a live call in real time. This can result in designing an
effective algorithm to reduce the handover latency in VoIP.
For mobile WiMAX user , the possible future work could be using a new algorithm that
can integrate the speed of the user and the other factors which may affects the quality of service
of the real time applications.
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List of References
4.3.1. Abdulmotaleb, El Saddik. "Quality of Service in Multimedia Networks." University of Ottawa, Ontario, Canada. n. page. Web. 7 Jan. 2013. <http://encyclopedia.jrank.org/articles/pages/6874/Quality-of-Service-in-Multimedia-Networks.html>.;
4.3.2. "Introduction to the Sensor and Location Platform in Windows (Windows)."