,,QoS Quality of Service QoS TCP-AV TCP,,,,,,, TCP-AV,, QoS TCP, LAN,QoS,

LAN QoS TCP : 2 : 21 3

,,QoS Quality of Service QoS TCP-AV TCP,,,,,,, TCP-AV,, QoS TCP, LAN,QoS,

abstract In late years, the demand for multimedia communication has been raised extensively guarantee the QoS is extremely important QoS defined here is to guarantee target bandwidth In order to realize it, TCP-AV has been proposed and implemented, and it is achieved in a wired environment However, wireless environment has problems different from the wired environment When multiple terminals are communicating, it is said that unfairness of the throughput among terminals is observed caused by control mechanism of the data transmission right As a result, there is a possibility that it cannot control the bandwidth effectively To Therefore we invested and considered about fairness in this paper We have used TCP-AV on wireless environment and evaluated performance of multimedia communication, for aiming at better QoS controls by resolving problems Kerwords TCP,wirelessLAN,QoS,fairness

ii 1 1 11 1 12 2 13 3 2 LAN 4 21 4 211 CSMA/CA 4 212 CSMA/CA TCP 6 213 MAC 8 22 9 221 UDP 9 222 TCP-Reno 10 223 TCP-AV 11 3 13 31 LAN TCP 13 311 13 312 14 32 15 321 16 322 OS 18 323 19 33 20

iii 331 AP 21 332 UDP 22 333 TCP 25 34 LAN TCP 26 341 26 342 UDP 27 343 TCP 29 4 TCP-AV 33 41 TCP-AV LAN 33 42 3 34 421 34 422 35 43 5 36 431 36 432 36 5 38 51 38 52 39 40 42 44

iv 21 5 22 TCP 7 23 8 24 TCP 9 25 10 26 MAC 11 27 12 31 LAN 14 32 TCP 3 14 33 TCP 4 15 34 TCP 5 15 35 TCP 6 16 36 TCP 7 16 37 17 38 17 39 LAN 17 310 LAN 18 311 LAN 18 312 OS 19 313 OS 1 19 314 OS 2 20 315 5 (Windows 3,Linux24 1,Linux26 1 ) 20 316 5 2(Windows 2,Linu24 1,Linux26 1 ) 21

v 317 5 3(Windows 3,Linux26 2 ) 21 318 5 4(Windows 4,Linux26 1 ) 22 319 5 5(Windows 4,Linux24 1 ) 22 320 AP 23 321 UDP 23 322 LAN (UDP) 25 323 LAN (UDP) 25 324 TCP 26 325 TCP 26 326 USB LAN 27 327 USB LAN 27 328 LAN (UDP) 28 329 LAN (UDP) 28 330 LAN TCP 29 331 LAN 25 29 332 LAN 20, 05% 30 333 30 334 TCP 31 335 tcpdump 31 41 TCP-AV LAN 33 42 AVR 34 43 AVR TCP-AV 1 3 35 44 AVR 36 45 AVR TCP-AV 2 5 37

1 1 11, VoIP QoS Quality of Service QoS, QoS,, TCP/IP, QoS, QoS 1 TCP-AV[1] TCP-AV, QoS, TCP TCP-AV,, QoS TCP-AV QoS, LAN,, VoIP,,, TCP-AV TCP,, QoS, VoIP, UDP

1 2 UDP,UDP, UDP,UDP TCP QoS QoS, [2],, TCP [3], LAN MAC, LAN AP Access Point TCP-ACK,, OS,, AP,, TCP-ACK, UDP,, AP, ACK, LAN LAN, TCP-AV 12, LAN QoS 1, LAN, LAN 11g TCP

1 3 LAN 11b, LAN,TCP-AV LAN, 2, QoS TCP,QoS TCP TCP-AV TCP-AV, LAN,, LAN TCP-AV, LAN QoS 13 2 LAN LAN,, 3 LAN, USB LAN 4 TCP-AV TCP-AV AVR 5

4 2 LAN 21, LAN TCP LAN TCP,, 0Mbps, fair-share 21,,, LAN, 211 CSMA/CA CSMA/CA Carrier Sense Multiple Access with Collision Avoidance,IEEE80211 LAN,, IFS: Inter Frame Space,,

2 LAN 5 faircase Unfaircase t h r o u g h p u t throughput 1 2 3 4 5 6 7 8 9 10 Terminal ID 1 2 3 4 5 6 7 8 9 10 Terminal ID throughput of all terminals are almost equal There are huge difference on throughput among terminals 21: (1) CSMA/CA 1, 80211 DIFS Distributed Coordination Function IFS,, CW Contention Window,,, CW 2 2, (2) 2 80211 LAN DCF Distributed Coordination Function,

2 LAN 6 CSMA/CA CSMA/CA,,,,,, MAC Media Access Control TCP,,, 212 CSMA/CA TCP TCP 1,RTT Round Trip Time, (1) TCP-ACK ACK,,, ACK, 10 10 1 ACK,,,, 1, 1 ACK,,,, 10 ACK,ACK,,,,

2 LAN 7 (2), AP ACK [3],10 AP 1 22, 11Mbps,ACK 100Mbps AP AP ACK,AP,10 ACK 1/11, AP ACK ACK ACK, 23 22: TCP,, 24 LAN 25, [4]

2 LAN 8 23: 213 MAC MAC, MAC, IEEE8023 CSMA/CD CSMA with Collision Detection, IEEE80211 CSMA/CA 2 CSMA/CD, (Carrier Sense),, (Collision Detection),,,1, (Multiple Access),USB 2 2 MAC USB MAC,CSMA/CA,,, CSMA/CD 26

2 LAN 9 24: TCP, USB,BUFFALO WLI-UC-AG[5],, BUFFALO WLI3-TX1-G54[6] BUFFALO WLI-TX4- G54HP[7] 22 LAN,, UDP TCP TCP TCP-Reno, QoS TCP-AV 221 UDP UDP, UDP,,,,

2 LAN 10 25: UDP 222 TCP-Reno TCP-Reno Linux TCP [8] TCP CA OPEN TCP,,,, TCP CA RECOVERY, TCP CA CWR, TCP CA LOSS 3, ACK SACK,Local Device Congestion, 27 Local Device Congestion NIC, TCP,,, ACK SACK,

2 LAN 11 Converter type USB type TCP IP TCP IP WLAN Ethernet USB WLAN Ethernet Ethernet converter <wireless> AP 26: MAC, 223 TCP-AV TCP-AV TCP,,, TCP,,,,,,SACK Selective ACK,,,

2 LAN 12 [increase of congestion window] TCP_CA_Open normal state duplicate ACK, SACK TCP_CA_Recovery abnormal state timeout ECN, ICMP source quench, Local device congestion TCP_CA_Loss abnormal state TCP_CA_CWR abnormal state 27:,,,,,,,,,

13 3 LAN QoS, LAN, LAN OS WindowsXP LinuxOS 24 26, BUFFALO WZR-AMPG300NH[9] Dummynet, LAN,IEEE80211g[10] 80211b LAN,,EB Effective Bandwidth,fair-share EB, 1 25Mbps, EB fair-share EB, 1 31 LAN TCP 311 LAN 80211b LAN,,TCP-AV,

3 14, 3 7 Iperf[11], 120 10,Windows Linux Iperf 64k, 25 322, 5 31: LAN 312 3 7 32 36 3 4,, 5 7 10, 32: TCP 3

3 15 33: TCP 4 34: TCP 5 MAC,, MAC,,,,,,, 32, OS

3 16 35: TCP 6 36: TCP 7, 321, (1), LAN 37 Iperf 120 38 20Mbps 25Mbps, IEEE80211g LAN,,WindowsXP LinuxOS,

3 17 Windows:4 Linux24:2 Linux26:2 Iperf:120sec converter <Wireless> IEEE80211g Dummynet Delay=25ms <wired> 37: 38: (2) LAN LAN LAN, Iperf 120 39 OS WindowsXP,Linux24,Linux26 Iperf:120sec Converter Windows or Linux24 or Linux26 <Wireless> IEEE80211g Dummynet Delay=25ms <wired> 39: LAN 310,,

3 18 LAN, WindowsXP LinuxOS, 310: LAN (3) LAN, LAN 311, EC3 EC2 EC4 AP EC1 EC5 311: LAN 322 OS,, OS 2 312 313 314 1 10,

3 19 1 2 converter converter OS :Windows XP or Linux OS Iperf:120sec <Wireless> IEEE80211g AP <wired> Dummynet (Delay=25ms) 312: OS,2 WindowsXP LinuxOS, LinuxOS,,314 OS 313: OS 1 323 5 OS, 322 Iperf 120, 315 319 1 10,,,, OS LAN,

3 20 314: OS 2 315: 5 (Windows 3,Linux24 1,Linux26 1 ),, LAN, OS 33, AP ACK

3 21 316: 5 2(Windows 2,Linu24 1,Linux26 1 ) 317: 5 3(Windows 3,Linux26 2 ) 331 AP (1), LAN AP LAN AP, AP, BUFFALO WZR-AMPG300NH[9] 320 1 UDP AP, [12],,,, 320, AP (2) AP 10 AP, 300,

3 22 318: 5 4(Windows 4,Linux26 1 ) 319: 5 5(Windows 4,Linux24 1 ), AP TCP-ACK 332 UDP UDP,,ACK TCP Iperf,UDP,,, 120 UDP 1470byte,Windows Linux Iperf UDP 64k, 100Mbps 25,10

3 23 AP (Buffalo) *example* Transmitting terminal Hello 1 Hello2 Add numbers on UDP packet(60byte) Hello1000 Hello 1 (1) Compare Hello 2 (2) added number by transmitter and times of receiving Hello100 (100) Hello 120(101) UDP packet came to AP s buffer until100 th packets consecutively However, packets between100 th and 120 th have lost, because of buffer overflow Receiving terminal Hello 1000 (700) 320: AP (1) 321 Windows Linux, Windows XP Linux OS AP AP Dummynet Delay=25ms Dummynet Linux OS Linux OS 321: UDP 31 Linux, Windows, AP wired,, EC LAN,USB USB LAN Linux USB IEEE80211g LAN, Linux, LAN, Linux Windows,

3 24 31: Linux Windows wired 93Mbps( 93Mbps ) 97Mbps( 90Mbps ) EC 92Mbps( 30Mbps ) 34Mbps( 33Mbps ) USB 27Mbps( 27Mbps ) AP,,USB, (2) LAN [2] TCP,, LAN, Iperf 120 10, 2 5 322, 5 323,, 5, 10,, 2 4 UDP, UDP,ACK,UDP TCP,TCP ACK

3 25 322: LAN (UDP) 323: LAN (UDP) 333 TCP TCP,,, Iperf 120 Windows Linux Iperf 64k 25 324 2 5 5 1 4 Windows, 5 Linux OS 325 10 CSMA/CA,AP, ACK 100Mbps

3 26 Linux OS Iperf:120sec <wired> Dummynet Delay=2,5ms <Wireless> IEEE80211g AP converter converter converter converter converter Windows XP Windows XP Windows XP Windows XP Linux OS 324: TCP 325: TCP,, AP, ACK,AP 34 LAN TCP,, LAN, 341, USB LAN 326 USB LAN 3, 1

3 27,UDP M,10M,100M TCP Iperf 326: USB LAN 327 UDP1M 10M,UDP100M TCP,, 327: USB LAN 342 UDP LAN UDP 328,,7 OS, 1 8 Linux24, 6 7 Linux26, 2 5 windows XP, 1,2,6,7, 3 5 USB 7 AP, 1 USB

3 28, MAC UDP 3 5 1 6 2 4 Windows XP Windows XP Linux OS 7 converter Windows XP converter Linux OS Windows XP Iperf:120sec converter converter Linux OS <Wireless> IEEE80211g AP <wired> Dummynet Delay=25ms Linux OS 328: LAN (UDP) 329: LAN (UDP) 329,,,USB fair-share EB 7 3Mbps,,,,,USB, [2] [3], 7,,TCP, UDP

3 29 343 TCP,UDP LAN TCP 330 7 OS, 1 8 Linux24, 6 7 Linux26, 2 5 windows XP, 1,2,6,7, 3 5 USB 7 AP, 1 USB, MAC 25, 20, 05% [13] Iperf:120sec Linux OS converter <Wireless> IEEE80211g <wired> Windows XP converter Windows XP Windows XP AP Dummynet Windows XP converter Delay=2,5ms or Delay=20ms Drop=05% Linux OS converter Linux OS Linux OS 330: LAN TCP USB-type Converter-type 331: LAN 25 25 331,,USB,

3 30 4 USB-type throughput[mbps] 3 2 1 0 1 2 3 4 5 6 7 terminal ID Converter-type 332: LAN 20, 05%, USB fair-share EB 7 3Mbps, fair-share, Mbps, 20, 05% 332,, 2 fair-share, Mbps 2,, MAC TCP [14] tcpdump, 226Mbps fair-share 504Kbps 2 333 333:

3 31 TCP 334, TCP 3, ACK SACK tcpdump, ACK 335,, ACK, 1 1, ACK, 334, 335,, Higher throughput 226Mbps Packet loss as well as retransmission are frequent [Packet] Lower throughput 504Kbps Time [sec] Packet loss is not frequent Time [sec] 334: TCP 335: tcpdump 2,,,,, ACK

3 32,,,ACK,, OS,, ACK,,,,,,,,,,,,,,

33 4 TCP-AV 41 TCP-AV LAN TCP-AV LAN 41, TCP TCP-Proxy, TCP TCP-AV, TCP-AV,, TCP TCP-AV flow TCP-Reno flow TCP-Proxy TCP converter < > AP 41: TCP-AV LAN

4 TCP-AV 34 42 3 421 3 LAN TCP-AV AVR 42,Flow1 TCP-AV, TCP, TCP TCP-Proxy, TCP TCP-AV Flow2,Flow3 TCP-Reno 10,,NRT Normalized Required Throughput,AVR Achievement Ratio NRT EB,, AVR, 120 5, 5, 23 23,10,TCP-AV,fair-share NRT 32% 8Mbps Windows XP Windows XP Windows XP <Wireless> IEEE80211g TCP-Proxy converter converter Iperf:120sec converter Flow1:TCP-AV Flow2:TCP-Reno Flow3:TCP-Reno Network emulator Delay=10ms switch <wired> Linux OS Linux OS Windows XP 42: AVR

4 TCP-AV 35 422 43 3flows NRT, AVR NRT,NRT100% 25Mbps,TCP-AV NRT %, 3flows, 42,TCP-AV 1 TCP-Reno 2 3, 9,NRT 40% TCP-Reno 1 2,TCP-AV 1 TCP-Reno 4 5 43 5flows, 9,,NRT 30%,fair-share 10%,,, CSMA/CA, 100 90 AVR(Achievement Ratio)[%] 80 70 60 50 40 30 20 10 0 0 20 40 60 80 100 NRT(NormalizedRequired Throughput)[%] 3 flows( ) TCP-AV- flow TCP-Reno-2 flows (1flows*2terminals ) 5 flows( ) TCP-AV- flow TCP-Reno-4flows (2flows*2terminals) 43: AVR TCP-AV 1 3

4 TCP-AV 36 43 5 431, 44 5 44: AVR 432 fair-share NRT 20% 5Mbps 45 fair-share AVR 100%, fair-share NRT 25%,AVR 70% 7 NRT 40% AVR 1,TCP-AV,fair-share, LAN TCP-AV,, 6

4 TCP-AV 37 45: AVR TCP-AV 2 5

38 5 51, QoS LAN, LAN(80211g),,,,,,AP UDP AP TCP-ACK,MAC USB, UDP, USB, 7 TCP, TCP tcpdump,,,, QoS TCP-AV, AVR,TCP-AV fair-share, 30%,TCP-AV,,

5 39, QoS 52, LAN, Windows LAN, QoS,,TCP-AV, QoS, TCP-AV TCP-AV TCP-AV

40 NEC 2 NEC,,NEC,, TCP-AV NEC 3

5 41

42 [1] HShimonishi, et al, Congestion Control Enhancements for Streaming Media, IEICE Tranc on Comn,VolE89 B, No9,pp2280-2291 Sep 2006 [2] DLeith, et al, Using the 80211e EDCF to Achieve TCP Upload Fairness over WLAN ling, IEEE,2005 [3] SPilosof,RRamjee,YShavitt,PSinha, Understanding TCP fairness over Wireless LAN INFOCOM 2003, 1-3 April 2003 [4] Anthony CH NG, David Malone, Douglas JLeith Experimental Evaluation of TCP Performance and Fairness in an 80211e Test-bed, ACM SIGCOMM 2005,pp17-22 Aug2005 [5] BUFFALO AirStation 54Mbps 80211 abg (WLI-UC-AG): http://buffalojp/products/catalog/network/wli-uc-ag/ [6] BUFFALO 24GH 54Mbps wireless LAN Ethernet conversion media converter (WLI3-TX1- G54 : http://buffalojp/products/catalog/item/w/wli3-tx1-g54/ [7] BUFFALO AirStation High Power wireless LAN Ethernet converter 54Mbps (WLI-TX4- G54HP) : http://buffalojp/products/catalog/item/w/wli-tx4-g54hp/ [8] Linux Kerner ver24 implementation: http://wwwlinuxorg/ [9] BUFFALO wireless LAN BB router AirStation NFINITI GIGA 300Mbps 11n conformity (WZR-AMPG300NH) : http://buffalojp/products/catalog/network/wzr-ampg30nh/

43 [10] IEEE80211 wireless LAN medium access control (MAC)and physical layer(phy) specification,1999 [11] Iperf: http://dastnlanrnet/projects/iperf/ [12] Perl program of inspect the size of buffer: http://x68000q-e-dnet/ 68user/net/udp-2html [13] Yumi Hirano, Tutomu Murase: Evaluation of Packet Loss Effect on Throughput Unfairness between TCP Upflows over IEEE80211 Wireless LAN, APSITT 2008, 22-24 April 2008 [14] : iscsi,, Vol J87-D-I, No 2, pp 216 231, 2004 2

44 1 LAN QoS TCP 19 (DEWS2008) 2008 3 2 QoS TCP 70 2008 3 3 Emi Arai Yumi Hirano Tutomu Murase Masato Oguchi Empirical Stdy on a Session Layer Resorce Control over Resorce Control over 80211 DCF Wireless LAN Asia-Pacific Symposium on Information and Telecommunication Technologies(APSITT2008) April 2008 4 LAN DICOMO2008 7 5 LAN QoS 2008 9 6 LAN QoS TCP

45 DEIM2009) 2009 3