Mobile Network Configuration for Large-scale Multimedia Delivery on a Single WLAN



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Mobile Network Configuration for Large-cale Multimedia Delivery on a Single WLAN Huigwang Je, Dongwoo Kwon, Hyeonwoo Kim, and Hongtaek Ju Dept. of Computer Engineering Keimyung Univerity Daegu, Republic of Korea {heegoang426, dwkwon, hwkim84, juht}@kmu.ac.kr Abtract We report performance meaurement and analye of a variety of wirele network to arrive at an appropriate network tructure configuration for mooth multimedia treaming ervice with a variety of mart device in a ingle wirele network environment. Unlike the uual infratructure network, configuration uch a the IEEE 82.11 ad hoc network and the Wi-Fi direct network ue direct connection between device without going through a wirele AP. Therefore, thee configuration prevent concentrating traffic at the wirele AP. We generated three type of wirele network performance meaurement and arrived at a uitable network for multimedia treaming ervice uing a variety of mart device. The wirele network wa configured in a tructure for efficient multimedia treaming ervice in a ingle wirele LAN environment, and ubequently, the network performance wa meaured. Keyword media treaming; ad hoc network; Wi-Fi Direct; video delivery I. INTRODUCTION Proviion of Internet ervice i preading becaue of the rapid proliferation of non-pc device, uch a mart mobile device, the pread of cloud computing, and emerging tandard, uch a N creen, that hare content among multiple device and platform [1]. Uing Miracat [2] technique, part of N creen technology, it i poible to hare multimedia content (muic, picture, and video with multiple device imultaneouly. However, uing thee technique to hare content on multiple device in an environment with a ingle wirele LAN i limited by the traffic generated. For example, multimedia treaming in a ingle wirele LAN environment, uch a a conference room or a claroom for a meeting or cla, to perhap 3 or more device while providing mooth multimedia treaming ervice i difficult becaue a large amount of traffic i concentrated on the wirele LAN. To olve the problem, one may conider a wirele ad hoc network configuration that enable a one-to-one connection among device intead of an Infratructure network. Unlike Infratructure network configuration, ad hoc network connect device with each other, independent of wirele acce point (AP, to tranfer data directly between device. Thi method of connection can reolve the problem of concentrated traffic on a wirele AP. However, the Android OS, which account for a large hare of mart device operating ytem, doe not upport the IEEE82.11 ad hoc network tandard for ecurity reaon. The configuration of uch a network i therefore not eay, needing adminitrator privilege to configure rooting. An alternative to uing imilar technique i Wi-Fi Direct. Wi-Fi Direct can be ued to tranfer data through a direct connection among mart device within thi new tandard announced by the Wi-Fi Alliance. Wi-Fi Direct can be ued without a wirele AP. Mot android OS device currently upport Wi-Fi Direct. Thi tudy ue a variety of mart device and laptop for performance meaurement of infratructure network, ad hoc network and Wi-Fi Direct network and preent an analyi of the reult. Baed on thee reult, wirele network tructure are configured to overcome the traffic limitation in a ingle wirele network environment when multimedia treaming, and the reulting performance i meaured. The remainder of thi paper i organized a follow. Section 2 decribe related work, and Section 3 decribe the contruction and tandard of wirele network. Section 4 decribe the performance meaurement of each type of wirele network and analyze the reult. Section 5, baed on the reult of Section 4 in a ingle wirele LAN environment, determine a wirele network uitable for multimedia treaming and performance meaurement of a multiple-connection wirele network whoe reult can be analyzed. In Section 6, a wirele network tructure i configured to overcome the traffic limitation of a ingle wirele network environment in which multiple device are engaging in multimedia treaming, and the reulting performance i meaured. Finally, in Section 7, we conclude the paper. II. RELATED WORK Exiting reearch on wirele environment focue on the high-peed tranfer rate and quality aurance of multimedia rather than on the contraint of traffic when multiple device invoke multimedia treaming. Thi reearch wa upported by the MSIP(Minitry of Science, ICT & Future Planning, Korea, under IT/SW Creative reearch program upervied by the NIPA(National IT Indutry Promotion Agency (NIPA- 13-(H52-13-199, and the Minitry of Education, Science Technology (MEST and National Reearch Foundation of Korea(NRF through the Human Reource Training Project for Regional Innovation(12H1B8A25942. Copyright IEICE - Aia-Pacific Network Operation and Management Sympoium (APNOMS 14

TABLE 1. ROUTING TABLE OF THE CONFIGURATION OF AN AD HOC NETWORK Detination Gateway Genmak Flag Metric Ref ue Iface 192.168.49. * 255.255.255. U eth R. AlTurki et al. [3] report work on upporting video treaming over ad hoc network and preent an analyi uing the OPNET imulation environment. They then evaluate the performance of a video treaming application over ad hoc network by imulating a few cenario while varying video quality, network ize, and 5 different routing protocol. The imulation demontrate that it i poible to tream fairly good quality video over medium ized ad hoc network. However, they do not conider multicat becaue they aume that each application require a unique connection. They note that a network with 9 node can upport up to 8 Kbp of multimedia traffic (reaonably high-quality video at 1% throughput. A network with 25 node could upport up to Kbp of traffic (medium quality video with 8% throughput. However, the throughput in larger network decreae rapidly with over 8% packet loe for fairly mall traffic rate. H. Yoon et al. [4] propoe Decentralized collaborative Media content Streaming (DOMS that realize flexible media content haring by exploiting collaborative egmentbaed treaming among Wi-Fi device via temporarilyetablihed direct link. The prototype device how improved haring performance by upporting twice a many concurrent device compared with conventional noncollaborative treaming at target media quality. T. Hwang et al. [5] propoed the Enhanced Adaptive Fat Replica (EAFR method to be able to tranfer content by ditributing the network traffic effectively uing the tranport bandwidth of the Digital Living Network Alliance (DLNA; a proxy i not ued in the tranmiion path. Z. Fu et al. [6] decribe the deign and implementation of a tranmiion control protocol (TCP-friendly tranport protocol for ad hoc network. The key novelty of their deign i to perform multi-metric joint identification for packet and connection behavior baed on end-to-end meaurement. Their NS-2 imulation how ignificant performance improvement over wired TCP-friendly congetion control and TCP with explicit-link-failure-notification upport in ad hoc network. S. Lee et al. [7] decribe a hop-baed priority (HBP technique uing 82.11e for enuring good Quality of Service (QoS of a multimedia treaming ervice. Multimedia treaming data packet are aigned a higher priority after every hop. Thi aignment can minimize the contention between the previou packet and the next packet. However, when many random route exit, ome route have a lower priority than other at the cro-route node and cannot obtain a channel. Thee reearch tudie motly conider the tranfer of content between a few device. Reearch i inufficient on a ingle wirele LAN environment uing multiple device tranferring content imultaneouly. Such an environment with multiple device ha a problem in that performance i not guaranteed becaue of traffic retriction. Thu, in thi paper, we meaure the performance of each wirele network and then identify the appropriate wirele network when treaming multimedia to multiple device III. WIRELESS NETWORK CONSTRUCTION AND STANDARDS Thi Section decribe the contruction of a tandard wirele network, uch a an ad hoc network; it alo decribe how to configure the network prior to the experiment, limiting the number of Wi-Fi Direct connection device, and how to configure the wirele LAN tandard when connecting between device to upport the wirele LAN. A. IEEE 82.11 Ad Hoc Network Configuration IEEE 82.11 ad hoc network are not upported on android device becaue of ecurity iue. There are two way to configure an ad hoc network with android device. Firt, it i poible to replace the IEEE 82.11 ad hoc network with a wpa_upplicant file [8]; thi file upport the IEEE 8211 ad hoc network configuration in obtaining adminitrator privilege on android device through rooting. A wpa_upplicant file i upported in wirele LAN ecurity tandard on android device. It i not eay to ue multimedia treaming by configuring ad hoc network in thi way becaue of rooting iue and change to ytem file. Secondly, an ad hoc network can be configured through a hotpot uing tethering. Thi method ha the advantage that it doe not need to be routed to when configuring the network. However, device not upporting tethering cannot configure ad hoc network. We tried to check the routing table of a configuration uing tethering in an ad hoc network to confirm the group owner of the connected device. In thi circumtance, the Group Owner i the device that created the hot pot for configuring the ad hoc network. Thi proce hould confirm whether traffic pae through the Group Owner when communicating between connected device. If it pae through the group owner, traffic i concentrated at the group owner, uch a an infratructure network. Thi mean that the ad hoc network wa not properly connected. Table 1 i the Routing table for an ad hoc network configured uing tethering. The Gateway i expreed a the * ymbol when the detination i 192.168.49.. Thi mean that the detination i reached directly, without going through an intermediate point when communicating over the internal network. Therefore, the network configuration uing tethering i an ad hoc network.

TABLE 2 DEVICES FOR THE PERFORMANCE MEASUREMENT OF WIRELESS NETWORKS Device name Manufacturer CPU Operating Sytem RAM Galaxy Note 1.1 Galaxy Tab 7. Optimu LTE2 Xnote Z2 Samung Electronic Samung Electronic LG Electronic LG Electronic ARM Holding Cortex-A9 Architecture 1.4GHz Quad Core 1GHz Single Core Qualcomm Krait Architecture 1.5GHz dual core Intel Mobile Core2 Duo T56 (Merom Wirele LAN Specification Android 4.1.2 Jellybean 2GB DDR2 SDRAM 82.11 a/b/g/n Android 2.3.6 Gingerbread 512MB DDR SDRAM 82.11 a/b/g/n Android 4.1.2 Jellybean 2GB LPDDR2 RAM 82.11 a/b/g/n Ubuntu 12.4.3 LTS ipad Apple 1GHz dual-core ARM Cortex-A9 ios 7.4 1GB DDR2 PC2-53 1GB LPDDR2 SDRAM 82.11 a/b/g 82.11 a/b/g/n B. Retriction of the Number of Connection of a Wi-Fi Direct Group When creating a Wi-Fi Direct group for more than 2 device, the group might have retriction impoed by the device manufacturer and by the performance of the group owner. The Group Owner i a device that can control and manage a group. The number of device in the group for thi experiment wa 5 unit plu the group owner. C. Wirele LAN Retriction when Supporting a Wirele Network Connection among Device Wirele LAN technology ha been etablihed a a et of 82.11x tandard. The wirele tandard mot mobile device currently upport i IEEE 82.11n. The IEEE 82.11n tandard i a reviion to improve the bandwidth of IEEE 82.11g and IEEE 82.11a. By uing a channel bandwidth of 4 MHz, IEEE 82.11n provide up to 6 Mbp maximum data tranfer rate. In contrat, the maximum data tranfer rate of IEEE 82.11g i 54 Mbp [9]. To ue the IEEE 82.11n tandard between two device, the following two condition mut be atified. Firt, both device mut upport IEEE 82.11n. Second, it i neceary to et the WPA2-PSK ecurity mode and to ue the AES encryption algorithm. Our experiment atifie thee condition. IV. WIRELESS NETWORK PERFORMANCE MEASUREMENTS In thi Section, we configure an Infratructure network, Wi-Fi Direct and an ad hoc network; we then meaure their performance and compare the reult. We ue thee reult to dicu network configuration uitable for multimedia treaming. A. Experimental Environment 1 Device and wirele LAN tandard for experiment The device ued for thi experiment are hown in Table 2. Thee device are not able to repreent the all mart device. However the validity of the experimental reult increaed by uing the Samung Galaxy Note and the LG Optimu in the Android OS device, which market hare i high. The wirele LAN tandard of the experiment were in IEEE 82.11 mode among all device except the laptop; the laptop ued IEEE 82.11g mode. The ad hoc network configuration ued the IEEE 82.11g mode becaue of the ecurity iue. The laptop ued a wirele LAN card upporting the IEEE 82.11n tandard; we configured the ecurity mode for tethering for the ad hoc network. It wa poible to connect in IEEE 82.11n mode. 2 Meaurement Method We meaured the Round Trip Time (RTT with ping and bandwidth with iperf for our performance meaurement of each wirele network. Each device ent 1 ping to the IP addre of it erver to meaure the mean value and average deviation for each RTT meaurement. Default value were ued for all parameter except for the number of ping. Bandwidth meaurement ued iperf to capture the TCP tranfer rate for packet from the client device to the erver. The erver had better performance when the device were interconnected becaue the network performance did not impact the device performance. Thi experiment tranmitted TCP packet for 1 econd from the client device to the erver device, after which the bandwidth wa meaured from the ize and number of packet tranferred. All parameter value were default except for the packet tranfer time and the etting of the client and erver. 3 The Wirele Network Configuration for Performance Meaurement. We configured wirele network for performance meaurement of an infratructure network, an ad hoc network and a Wi-Fi Direct network. The performance of the infratructure network wa meaured with public AP and private AP. A number of device connected to the public AP that were not participating in the experiment. Thi method wa ued to tudy the effect of the number of device connected to the wirele AP on the performance of the network. Ten or more device not ued in the experiment were connected to the public AP. In contrat only four connected device to the private AP were ued in the experiment.

The configuration of the IEEE 82.11 ad hoc network wa to create a hotpot with the group owner tethered. The other device were connected to the group owner. Only the Samung Galaxy Note 1.1 and Optimu LTE2 upport Wi-Fi Direct. Therefore, we meaured Wi-Fi Direct performance uing only thee two device. B. Experimental Reult Figure 1 i a graphic repreentation of the RTT and bandwidth meaurement reult for the wirele network. Performance value were imilar uing the Wi-Fi Direct and IEEE 82.11 ad hoc network and lower in the network Infratructure configuration. In cae RTT, the tranmiion delay time of the latter wa higher than that of the IEEE 82.11 ad hoc network and Wi-Fi Direct, which tranmitted directly between device becaue the infratructure network tranmit the ping between device via the wirele AP, i.e., the number of hop increae. In cae bandwidth, performance may be degraded due to channel interference in the vicinity of the wirele AP and beaconing. Additionally, a lower performance value wa meaured for the infratructure network than for the directly connected device. When a packet i received by the wirele AP, it i proceed for uch purpoe a packet filtering (for ecurity problem before being tranmitted to it detination. Therefore, the performance decline in the network Infratructure cenario. Furthermore, the RTT value increae when many device are connected to the wirele AP; it proceing peed low down due to it tak in ecurity management, uch a packet filtering and network management. The reult i that the IEEE 82.11 ad hoc and Wi-Fi Direct network are more table when treaming multimedia than the infratructure network. The IEEE 82.11 ad hoc and Wi-Fi Direct network, in contrat to the infratructure network, are unaffected by proceing delay becaue their traffic doe not pa through the wirele AP. However, configuring the IEEE 82.11 ad hoc network i not eay. In contrat, mot Android device upport Wi-Fi Direct, facilitating an eay etup. Thu Wi-Fi Direct i more uitable for multimedia treaming. V. PERFORMANCE MEASUREMENT OF MULTIPLE DEVICES USING WI-FI DIRECT In thi Section, we decribe performance meaurement with an increaing number of device connected by Wi-Fi Direct and dicu the reult. The method for meauring the performance wa the ame a that decribed in Section 4. A. Experimental Environment 1 Device for the experiment and the wirele LAN tandard The Samung Galaxy player 5.8 wa ued in thi experiment. It CPU i an ARM Holding Cortex-A9 architecture 1 GHz dual-core, and it operating ytem i Android 4..4 ( Ice Cream Sandwich. Memory wa 1GB EER 2 SDRAM; wirele tandard upported are IEEE 82.11a/b/g/n. The maximum number of connected device 18 16 14 1 1 (m T 8 R 6 4 Public A P Private A P IEEE 82.11 A d hoc W ifi D irect RTT Bandw idth Fig. 1. Performance meaurement of wirele network i 5, except for the group owner when thi device create a group. We ued the IEEE 82.11n mode becaue it upport higher throughput than IEEE 82.11g. Wi-Fi Direct upport WPA2-PSK/AES ecurity tandard, and the device ued for thi experiment upported the IEEE 82.11n mode. 2 Method of Meaurement RTT and bandwidth were meaured while increaing the number of device connected to the group owner, one at a time; the change in performance were meaured a a function of the number of device. When RTT and bandwidth were meaured, the group owner acted a a erver; device that participated in the group (except the group owner were client. The client device ent a TCP packet and pinged the erver imultaneouly. The Group Owner examined the throughput when it received a TCP packet and pinged the equipment imultaneouly. The environment to meaure bandwidth and RTT wa the ame a that decribed in Section 4. B. Experimental Reult Figure 2 how the meaurement of RTT and bandwidth with multiple device uing Wi-Fi Direct. For RTT, an average value of approximately 26m wa maintained depite increaing the number of connected device. Thi number i imilar to the Wi-Fi Direct RTT meaurement reult decribed in Section 4. Becaue device in Wi-Fi Direct connect directly, the path of the RTT meaurement of 35 3 25 (m T 15 R 1 5 1 device 2 device 3 device 4 device 5 device RTT Bandw idth Fig. 2. Performance meaurement of connecting multiple device uing Wi-Fi Direct 3 25 15 1 5 3 25 15 1 5 c / e it b (M th id w d n a B c / e it b (M th id w d n a B

Wi-Fi Direct i the ame. Therefore, the number of device doe not affect the RTT value. However, bandwidth value decreae in invere proportion to the increaing number of device. Wi-Fi Direct device ue the ame channel. Configuring a network uing Wi-Fi Direct for the mooth ue of multi-media treaming with multiple device i almot impoible becaue of the problem of bandwidth reduction due to the ue of the ame channel. Therefore, wirele network tructure configuration i required to olve thi bandwidth problem. VI. WIRELESS NETWORK CONFIGURATION FOR MULTIMEDIA STREAMING AND ITS MEASURED PERFORMANCE In thi Section, a wirele network tructure i uitably configured for multimedia treaming, and it performance i meaured. A. Wirele Network Configuration for Multimedia Streaming Progre in treaming i difficult when uing only a ingle wirele network and multiple device. Wi-Fi Direct retrict the number of device connection; therefore, it i difficult to connect multiple device. Additionally, when uing an infratructure network, traffic i concentrated at the wirele AP; therefore, uing the infratructure network for treaming i difficult. Hence, we have combined Wi-Fi Direct with an infratructure network for mooth multimedia treaming. Figure 3 how the network configuration. Six device are connected uing Wi-Fi Direct a a ingle group; thi i for implementing multimedia treaming to thee group. For example, uing five Wi-Fi Direct group at once upport multimedia treaming to 3 unit. The Wi-Fi Direct group owner are then configured in an infratructure network uing a wirele AP. With the network configured in thi way, communication i poible between a Wi-Fi Direct group owner and every other device by exchanging multimedia data uing the infratructure network; the Group Owner of each group tranmit multimedia data it receive to it group. Fig. 3. Wi-Fi direct and Infratructure network configurated for multimedia treaming B. Performance Meaurement The experimental environment wa configured, and it performance wa meaured uing the network tructure already preented. We ued the Samung Galaxy player 5.8, Samung Galaxy note 1.1 and a Samung note 1.1, 14 edition (Galaxy 14 for brevity in thi experiment. The Galaxy 14 pecification are a follow. The CPU wa an ARM Holding Cortex-A15 architecture 1.3 GHz quad-core and ARM Holding Cortex-A7 architecture 1.3 GHz quad core, the operating ytem wa Android 4.3 Jelly bean, and memory (RAM wa 3GB LPDDR3 SDRAM; the wirele tandard upported were IEEE 82.11a/b/g/n/ac. The limiting number of connected device wa 7, except for the group owner, when group were created uing thi device. The pecification of the Galaxy Player 5.8, the experimental equipment of Section 5, and the pecification of the Samung Galaxy note 1.1 are lited in Table 1. The Wi-Fi Direct network wa configured uing the Samung Galaxy player 5.8 and Samung Galaxy 14. In thi cenario, the Galaxy 14 wa the group owner. Improved performance wa expected from the group owner in the Wi-Fi Direct network configuration becaue the impact of the device on network performance wa removed. Here, the Galaxy 14 that wa alo connected to the wirele AP could be ued in the infratructure network. However, the Galaxy player wa not connected to the wirele AP; therefore, it infratructure network configuration wa not poible. The infratructure network wa configured by connecting a Samung Galaxy note 1.1 to the wirele AP to which the Samung Galaxy 14 wa connected. At thi time, the wirele AP wa connected only to the Samung Galaxy 14 and to the Samung Galaxy note 1.1. The environment to meaure bandwidth and RTT wa the ame a the performance meaurement environment decribed in Section 4. When RTT and bandwidth were meaured, the Samung Galaxy 14 wa a erver, and the other device were client. When uing a multimedia treaming environment configuration, both Wi-Fi Direct and infratructure network wa configured, and the Galaxy 14 wa part of both. Thu, the meaurement of performance i required when TCP packet and ping are focued on thi device. C. Reult of the Experiment Figure 4 and 5 are the meaured performance reult uing the combination of a Wi-Fi Direct and infratructure network. The RTT and bandwidth of the Wi-Fi Direct configuration had meaured value imilar to thoe reported in Section 5, with five device connected to the group owner. However, when the infratructure network wa configured, the RTT value meaured wa ignificantly lower and comparable to that reported in Section 4. The reaon for thi reult i that TCP packet for meauring bandwidth pa through the wirele AP. Becaue the wirele AP manage ecurity, uch a packet filtering, the maximum TCP throughput i reduced. Wi-Fi Direct device group and the

infratructure network connect uing the ame channel; Fig. 4. The performance meaurement of a network tructure for multimedia treaming: RTT Fig. 5. The performance meaurement of a network tructure for multimedia treaming: Bandwidth therefore, the bandwidth decline. Additionally, performance may be degraded due to channel interference and beaconing. Configuring a mobile network uing thi topology for the mooth ue of multimedia treaming with multiple device i almot impoible becaue of the limitation of network traffic proceing performance of the wirele AP between group owner. However, it can be olved uing a high performance wirele AP. Therefore, thi topology i appropriate for large-cale multimedia delivery on a ingle WLAN. VII. CONCLUSION A mart device become dieminated and more popular, N creen technology that provide content to multiple creen i preading. However, the iue of traffic limit that arie when uing multiple device imultaneouly ha not yet been reolved. In particular, technique to increae traffic are inufficient when multimedia treaming i ued on multiple device. Therefore, we need to meaure the performance of the wirele network in configuration that can overcome the traffic limitation and can allow for multimedia treaming. Wirele network were configured uing an infratructure network, an ad hoc network, and a Wi-Fi Direct network. The performance of thee configuration wa meaured for RTT and bandwidth. The performance of the ad hoc and Wi-Fi Direct network were imilar; both had higher performance than an infratructure network. However, ad hoc network are not eay to configure. It i eay, however, to conduct multimedia treaming by configuring the network uing Wi-Fi Direct. We looked for a change in performance when uing Wi- Fi Direct to connect to multiple device. We found imilar RTT value, but bandwidth wa inverely proportional to the number of device. Thi reult indicate that configuring a network for multimedia treaming to multiple device i not a mooth proce. Furthermore, Wi-Fi Direct retrict the number of connected device depending on the manufacturer and performance. Thu, the configuration of the network i difficult uing multiple device. We have propoed a method to configure a network for multimedia treaming uing both Wi-Fi Direct and an infratructure network. We created a number of eparate Wi- Fi Direct group, each of whoe group owner were configured in an infratructure network. We meaured the performance of thi network tructure through RTT and bandwidth meaurement. The RTT and bandwidth of Wi-Fi Direct wa imilar to that decribed in Section 5, in which Wi-Fi Direct had 5 device connected to the group owner. When an infratructure network wa added, the meaured RTT value wa imilar to the meaured performance reult provided in Section 4. In contrat, the bandwidth were ignificantly lower. However, it can be olved uing wirele AP of high performance. Therefore, thi topology i ued for large-cale multimedia delivery on a ingle WLAN. REFERENCES [1] C. Yoon, H. Lee and W. Ryu, Claification of N-Screen Service, Scenario and it Standardization, ICACT Tranaction on Advanced Communication Technology, vol.2, pp.214-222, May 13. [2] Wi-Fi Certificated Miracat: Extending the Wi-Fi experience to eamle video diplay, Wi-Fi Alliance, Jan. 13. [3] R. AlTurki and R. Mehmood Multimedia Ad hoc Network: Performance Analyi, in Proc. UKSIM European Sympoium on Computer Modeling and Simulation, pp.561-566, Sep. 8. [4] H. Yoon and J. Kim, Collaborative Streaming-baed Media Content Sharing in WiFi-enabled Home Network, IEEE Tranaction on Conumer Electronic, vol.56, no.4, pp.2193-2, Nov. 1. [5] T. Hwang, H. Park, E. Paik, and J. Chung, EAFR-Baed DLNA Proxy for High-Quality Video Ditribution in Extended Home Space, IEEE Tranaction on Conumer Electronic, vol.57, no.1, pp.1-125, Feb. 11. [6] Z. Fu, X. Meng, and S. Lu, A Tranport Protocol for Supporting Multimedia Streaming in Mobile Ad Hoc Network, IEEE Journal On Selected Area In Communication, vol.21, no.1, pp.1615-1626, Dec. 3. [7] S. Lee and C. Yoo, Hop-Baed Priority Technique Uing 82.11e for Multimedia Streaming, IEEE Tranaction on Conumer Electronic, vol.56, no.1, pp.48-53, Feb. 1. [8] Linux WPA/WPA2/IEEE 82.1X Supplicant, Available: http://hotap.epitet.fi/wpa_upplicant [9] O. O. Oluegun and C. E. Tan, TCP Throuput Efficiency Enhancement In IEEE 82.11n Network, in Proc. International Conference on Information Technology in Aia, Jul. 13.