Analysis of Video Conferencing on LTE Network

ENSC 427: COMMUNICATION NETWORKS SPRING 2013 FINAL PROJECT Analysis of Video Conferencing on LTE Network http://www.sfu.ca/~zza36/427eric3.html TEAM #12 Xu Jiang 301096225 xja6@sfu.ca Zhuopei Zhao 301109378 zza36@sfu.ca Freda Feng 301065666 xfa2@sfu.ca

Table of Contents Table of Contents... 2 List of Acronyms... 4 List of Figures and Tables... 5 Abstract... 6 Introduction... 7 LTE Network... 7 Video Conferencing... 7 OPNET Implementation... 8 LTE Architecture... 8 OPNET Simulation Topology... 8 LTE Model with Single enodeb... 8 LTE Model with Multiple enodebs... 9 LTE Network Test Case... 10 Case 1: Single enodeb with different bandwidth... 10 Case 2: Multiple enodebs with different bandwidth... 10 Case 3: Same bandwidth with different number of enodeb... 11 Discussion... 12 Case 1: Single enodeb with different bandwidth... 12 Case 1.1: Global Traffic Sent... 12 Case 1.2: Global Traffic Received... 13 Case 1.3: Global LTE Uplink Throughput... 14 Case 1.4: Global LTE Downlink Throughput... 14 Case 1.5: Global LTE Uplink Delay... 15 Case 1.6: Global LTE Downlink Delay... 16 Case 2: Multiple enodebs with different bandwidth... 16 Case 2.1: Global LTE Uplink Throughput... 17 Case 2.2: Global LTE Downlink Throughput... 17 Case 2.3: Global Traffic Received... 18 Case 2.4: Global Traffic Sent... 19 Case 2.5: Global LTE Uplink Delay... 19 Case 2.6: Global LTE Downlink Delay... 20 Case 3: Same bandwidth with different number of enodeb... 20 Case 3.1: Global traffic received... 21 Case 3.2: Global traffic sent... 21 Case 3.3: Packet Delay Variation for user one... 22 Conclusion... Error! Bookmark not defined.

Future Work... Error! Bookmark not defined. REFERENCES... 24 APPENDIX... 25

List of Acronyms EPC E-UTRAN HSS LTE MME OFDMA QoS PCRF P-GW SC-DMA S-GW UE 3GPP Evolved Packet Core Evolved Universal Terrestrial Radio Access Network Home Subscriber Server Long-Term Evolution Mobility Management Entity Orthogonal Frequency-Division Multiple Access Quality of Service the Policy Control and Charging Rules Function Packet Data Network Gateway Single-Carrier Frequency-Division Multiple Access Serving Gateway User Equipment 3 rd Generation Partnership Project

List of Figures and Tables Figure 1: The Architecture of LTE Network Figure 2: OPNET LTE Network with Single enodeb Figure 3: OPNET LTE Network with Multiple enodebs Figure 4: Global Traffic Sent for Different Bandwidths of Network 1 Figure 5: Global Traffic Received for Different Bandwidths of Network 1 Figure 6: Global LTE Uplink Throughput for Different Bandwidths of Network 1 Figure 7: Global LTE Downlink Throughput for Different Bandwidths of Network 1 Figure 8: Global LTE Uplink Delay for Different Bandwidths of Network 1 Figure 9: Global LTE Downlink Delay for Different Bandwidths of Network 1 Figure 10: Global LTE Uplink throughput for Different Bandwidths of enodeb in Network 2 Figure 11: Global LTE Downlink Throughput for Different Bandwidths of enodeb in Network 2 Figure 12: Global Traffic Received for Different Bandwidths of enodeb in Network 2 Figure 13: Global Traffic Sent for Different Bandwidths of enodeb in Network 2 Figure 14: Global LTE Uplink Delay for Different Bandwidths of enodeb in Network 2 Figure 15: Global LTE Downlink Delay for Different Bandwidths of enodeb in Network 2 Figure 16: Global Traffic Received for Network 1 and Network 2 with Same Bandwidth Figure 17: Global Traffic Sent for Network 1 and Network 2 with Same Bandwidth Figure 18: Packet Delay Variation for User One in Network 1 and Network 2 with Same Bandwidth Figure 19: Users Parameter Part 1 Figure 20: Users Parameter Part 2 Figure 21: Video Conferencing Parameter Figure 22: Application Parameter Figure 23: Profile Parameter

Abstract LTE, which is short for Long-Term Evolution, is a standard for wireless communications technology. It is widely used by many countries as the latest high speed mobile broadband technology. Video conferencing is a telecommunication technology which can allow two or more different locations communicating each other. It has becomes more and more important in daily life with the trend of using smart phones and tablets. We can find video conferencing is supported by many network applications, such as Skype, Talk box, ichat and so on. The performance of video conferencing using LTE network will be simulated using OPNET 16.0, which includes the uplink throughput, downlink throughput, uplink delay and downlink delay.

Introduction LTE Network LTE is a standard for mobile data communications technology. The idea of LTE was first proposed by NTT DoCoMo of Japan in 2004, and the official LTE work item started in 2006.Finally, the initial deployments of LTE began in late 2009by the 3 rd Generation Partnership Project (3GPP) as the fourth generation (4G) mobile-telecommunications technology and the first commercial LTE networks were launched in Norway and Sweden in December 2009.The goal of LTE is to increase the capacity and speed of wireless data networks. So far there are more than 117 commercial LTE networks in our commercial service. Comparing with other network technologies, LTE has many advantages. It improved the Quality of Service (QoS) and data transfer rate, such as downlink rate of at least 100 Mbit/s and uplink rate of at least 50 Mbit/s which at the same time reduces the problem of lagging while connecting the internet. LTE supports more data capacity of wireless network and allows more users to use LTE network. Besides, LTE also lower the data transfer latency which is less than 5 ms. By using OFDMA for downlink an SC-FDMA for uplink for LTE, it conserves more power to make the device been used for longer time. LTE has widened the scalable carrier bandwidths from 1.4 MHz to 20 MHz. Video Conferencing Video conferencing has become to a more and more popular convenient technology in the world for communication. It is not only used for big companies on their important long distance meetings, but also widely used in normal life with the trend to have smart phones and tablets. The technology of video conferencing let people communicate to each other anytime at different locations to make communication more convenient.

OPNET Implementation LTE Architecture In LTE network, the most important core network is Evolved Packet Core (EPC) network which can overall control the User Equipment (UE) within LTE network and establishing the bearers. EPC mainly consists of PDN Gateway (P-GW), Serving Gateway (S-GW) and Mobility Management Entity (MME) and other components such as Home Subscriber Server (HSS) and the Policy Control and Charging Rules Function (PCRF). Besides the core network, LTE also has an important access network which known as E-UTRAN that consists of enodebs.shown as Figure 1. Figure 1: The Architecture of LTE Network OPNET Simulation Topology In this project, it contains two test cases for analyzing the video conferencing in LTE network. First network, we simulated the video conferencing in different bandwidths base on same geographical topology and compared their result. Second network, we simulated the video conferencing in different cell and compared the result with the first network. LTE Model with Single enodeb Figure one is the topology of our first network. We used the OPNET Application

Definition to set up the high resolution Video Conferencing. Also, I set all user transfer data between each others. Then, I added 5MHz, 10MHz, 15MHz bandwidth in the LTE Attribute, so I can chose different bandwidth in the enodeb. Next, I created four more scenarios by duplicating the base topology, and changed the bandwidth for each scenario. The users, application, profile, and LTE parameters are shown in the Appendix. Figure 2: OPNET LTE Network with Single enodeb LTE Model with Multiple enodebs Figure two is the topology of our second network. We used the same setting for the video conferencing and users. We added one more EPC and enodeb into our first topology and configured the user_one under the new enodeb coverage. Therefore, the data transmitter to user_one from other users is between different cells. We run the simulation on 20MHz bandwidth and compare the result with network one which also is also on 20 MHz bandwidth. The users, application, profile, and LTE parameters are shown in the Appendix.

Figure 3: OPNET LTE Network with Multiple enodebs LTE Network Test Case We will set up 3 cases with different conditions to simulate LTE network. These cases were designed to compare the topologies with different network bandwidth, number of enodebs. Case 1: Single enodeb with different bandwidth This case was designed to test the performances of LTE network with different bandwidth (lower bandwidth of 1.4 MHz and higher bandwidth of 20 MHz) using single enodeb and four UEs. We will compare the results of Traffic Sent (bytes/sec) and Traffic Received (bytes/sec) for both enodeb and User 1. Besides that, we will also compare the time of Downlink Delay (sec), Uplink Delay (sec), Downlink Throughput (bits/sec) and Uplink Throughput (bits/sec). Case 2: Multiple enodebs with different bandwidth This case was designed to test the performances of LTE network with different bandwidth (lower bandwidth of 1.4 MHz and higher bandwidth of 20 MHz) using multiple enodebs with User 1 under one of the enodeb and the other three under the other enodeb. We will compare the results of Traffic Sent (bytes/sec) and Traffic Received (bytes/sec) for both enodeb and User 1. Besides that, we will also compare the time of Downlink Delay (sec), Uplink Delay (sec), Downlink Throughput (bits/sec) and Uplink Throughput (bits/sec).

Case 3: Same bandwidth with different number of enodeb This case was designed to test the performances of LTE network with same bandwidth 20MHz under different enodeb. We will compare the results of Traffic Sent (bytes/sec) and Traffic Received (bytes/sec) for both enodeb and User 1. Besides that, we will also compare the time of Downlink Delay (sec), Uplink Delay (sec), Downlink Throughput (bits/sec) and Uplink Throughput (bits/sec).

Discussion Our simulation runs for 5 minutes in order for the users to send and receive enough data and we set the data transfer start time between 90 seconds to 110 seconds in order for observer clearly know when the data be transferred. We compared the Global Traffic Sent, Global Traffic Received, LTE Uplink and Downlink Delay, LTE Uplink and Downlink Throughput between different Bandwidths of enodeb in a same network. We also compared the same statistics between different networks that have same Bandwidth of enodeb. Case 1: Single enodeb with different bandwidth We built four scenarios; all scenarios have the same network topology (network 1). However each scenario has different Bandwidths of enodeb: 20MHz, 10MHz, 15MHz and 1.4MHz.We will analysis results of four different scenarios. Case 1.1: Global Traffic Sent The following graph shows that the comparison of Global Traffic Sent of four different scenarios. Figure 4: Global Traffic Sent for Different Bandwidths of Network 1 As expected, the scenario, which has lowest Bandwidth (1.4MHz), has the lowest traffic sent rate. However, the rest scenarios have exactly value, which make no sense. We expected that a different Bandwidth of enodeb lead a Traffic sent rate. We think

this problem occurs because the network is too simple; we do not have enough users or enodebs in order to show the different. However, we add an enodeb to the network and solved this problem. The graphs and analysis is in the section of Comparison between different Bandwidths of enodeb in network 2. Case 1.2: Global Traffic Received Figure 5: Global Traffic Received for Different Bandwidths of Network 1 Again, the scenario, which has lowest Bandwidth (1.4MHz), has the lowest traffic received rate. However, the rest scenarios have exactly value, which make no sense. Similarly, we think this problem occurs because the network is too simple; we do not have enough users or enodebs in order to show the different. We can see the difference in the simulation of network 2. The graphs and analysis is in the section of Comparison between different Bandwidths of enodeb in network 2.

Case 1.3: Global LTE Uplink Throughput Figure 6: Global LTE Uplink Throughput for Different Bandwidths of Network 1 Similarly, form the graph above, we only can see the difference for the 1.4MHz Bandwidth scenario. The rest are all overlap. Again, the problem is network 1 has not enough users or enodebs in order to show the difference. We can see the difference in the simulation of network 2. The graphs and analysis is in the section of Comparison between different Bandwidths of enodeb in network 2. Case 1.4: Global LTE Downlink Throughput Figure 7: Global LTE Downlink Throughput for Different Bandwidths of Network 1

Same situation for the Global LTE Downlink Throughput, 1.4 MHz Bandwidth has the lowest Downlink Throughput. The rest are same. We can see the difference in the simulation of network 2. The graphs and analysis is in the section of Comparison between different Bandwidths of enodeb in network 2. Case 1.5: Global LTE Uplink Delay Figure 8: Global LTE Uplink Delay for Different Bandwidths of Network 1 From the graph above, we can tell that scenario that has 1.4MHz Bandwidth has a much larger Uplink delay than others. The rest scenario s delays are all almost 0. We think the reason that there is no delay for Bandwidth 20MHz, 15MHz and 10MHz is the value of users or enodeb or data transferred is too small, they can easily handle this small traffic. However, we built network 2that has more enodeb; the delays and the difference appear in the simulation of network 2. The graphs and analysis is in the section of Comparison between different Bandwidths of enodeb in network 2.

Case 1.6: Global LTE Downlink Delay Figure 9: Global LTE Downlink Delay for Different Bandwidths of Network 1 Similarly, 1.4MHz Bandwidth has a much larger Downlink delay than others. The rest scenario s delays are all almost 0. Again, we think the reason that there is no delay for Bandwidth 20MHz, 15MHz and 10MHz is the value of users or enodeb or data transferred is too small, they can easily handle this small traffic. However, we built network 2, which has more enodeb, the delays and the difference appear in the simulation of network 2. The graphs and analysis is in the section of Comparison between different Bandwidths of enodeb in network 2. Case 2: Multiple enodebs with different bandwidth In the last section we analyzed results of the simulation of network 1. However we could not see the difference between 10MHz and 20MHz Bandwidth enodebs. So, in this section, we add one more enodeb and EPC to build the network 2. We created two scenarios one with 10MHz Bandwidth enodeb and one with 20MHz Bandwidth enodeb.

Case 2.1: Global LTE Uplink Throughput Figure 10: Global LTE Uplink throughput for Different Bandwidths of enodeb in Network 2 This time we can see the difference. Blue-line stands for 10MHz, Red-line stands for 20MHz. From the graph we can tell that 20MHz Bandwidth has a higher Uplink Throughput rate than 10MHz Bandwidth. As you can see, the red line is not only higher than the blue line, but also more stable than the blue line. Case 2.2: Global LTE Downlink Throughput Figure 11: Global LTE Downlink Throughput for Different Bandwidths of enodeb in Network 2

Similarly, Blue-line stands for 10MHz, Red-line stands for 20MHz. From the graph we can tell that 20MHz Bandwidth has a higher Downlink Throughput rate than 10MHz Bandwidth. As you can see, the red line is not only higher than the blue line, but also more stable than the blue line. Case 2.3: Global Traffic Received Figure 12: Global Traffic Received for Different Bandwidths of enodeb in Network 2 Again, Blue-line stands for 10MHz, Red-line stands for 20MHz. As you can see from the graph above 20MHz Bandwidth has a higher Global Traffic received rate value than 10MHz Bandwidth and the result is more stable.

Case 2.4: Global Traffic Sent Figure 13: Global Traffic Sent for Different Bandwidths of enodeb in Network 2 However, from the graph above, both scenarios give us the same value of Global Traffic sent rate. Case 2.5: Global LTE Uplink Delay Figure 14: Global LTE Uplink Delay for Different Bandwidths of enodeb in Network 2 Obviously, 10MHz Bandwidth has a larger Uplink delay than 20MHz Bandwidth. The average delay of 10MHz Bandwidth is around 0.024s; however, the average delay of 20MHz Bandwidth is 0.017s.

Case 2.6: Global LTE Downlink Delay Figure 15: Global LTE Downlink Delay for Different Bandwidths of enodeb in Network 2 From the graph above, they both have a very close value of Downlink Delay. However, at the beginning of transferring data around 2m0s, 10MHz Bandwidth has a 0.008s delay and 20MHz Bandwidth has a 0.003s delay. Case 3: Same bandwidth with different number of enodeb In this section, we compared the result between network 1 and network 2. We set same parameters in both networks. The only difference between two networks is that they have different topology. Network 1 includes 4 users 1 EPC and 1 enodeb, on the other hand, network 2 includes 4 users, 2 EPCs and 2 enodebs.

Case 3.1: Global traffic received Figure 16: Global Traffic Received for Network 1 and Network 2 with Same Bandwidth According to the graph, we can say that network 1 has a higher value of Global traffic received rate than network2 does. Network 1 s Global traffic received rate is around 1,400,000 bytes/sec; on the other hand, Network 2 s Global traffic received rate is around 700,000 bytes/sec. Case 3.2: Global traffic sent Figure 17: Global Traffic Sent for Network 1 and Network 2 with Same Bandwidth

Similarly, According to the graph, we can say that network 1 has a higher value of Global traffic sent rate than network2 does. Network 1 s Global traffic sent rate is around 1,400,000 bytes/sec, however, Network 2 s Global traffic sent rate is around 700,000 bytes/sec Case 3.3: Packet Delay Variation for user one Figure 18: Packet Delay Variation for User One in Network 1 and Network 2 with Same Bandwidth As you can see from the graph above, network2 has a larger Delay than network1 does.

Future Work To obtain further insight and better tuning of our simulation s performance, there are several aspects of the simulation that could use further work. Having small bandwidth different between each scenario, such as 2MHz bandwidth difference, would simulate video conferencing situation that more realistic. Also, having an moving object between different cell during the video conferencing also can make the simulation more realistic. Conclusion In conclusion, our OPNET results agree with the theory. As expected, increasing the bandwidth will increase the data transmit rate and decrease the delay. Also, data transmit rate under the same cell coverage is faster than under different cells coverage. This project presented several challenges, such as setting attributes to make the users can send the data to each other. Form this project, we learn about that bandwidth is one of the key element of affecting the quality of data transmit under LTE network. Also, we learned about the technical aspects of LTE network and OPNET is powerful simulation software and enabled us to determine a good set of scenarios to run.

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APPENDIX Figure 19: Users Parameter Part 1 Figure 20: Users Parameter Part 2 Figure 21: Video Conferencing Parameter Figure 22: Application Parameter

Figure 23: Profile Parameter Figure 24: enodeb Parameter Figure 25: EPC Parameter Figure 26: LTE_Attributes Parameter