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數路 2003 Symposium on Digital Life and Internet Technologies UMTS 料流類路行 Behavior Study of UMTS QoS Classes on DiffServ Networks 李瑩李連立北路 64 s8842, s8839, lien@cs.nccu.edu.tw UMTSUniversal Mobile Telecommunication System 料流類串流類都 DiffServ 不料流不理 QoS NS-2 DiffServ UMTS 料流 DiffServ 不料流類 Best-Effort DiffServ 兩 QoS DiffServ 不類料流度 DiffServ 度度路, 路 Abstract UMTS defines four different types of traffic classes: conversational, streaming, interactive and background, each of them has specific characteristics. DiffServ can give packets various forwarding treatments according to different traffic classes to achieve the QoS goals. This study uses NS-2 simulator to study the behavior of all classes of traffic on DiffServ domain. Experiment 1 compares the performance of four traffic classes in the traditional Best-Efforts network and in the DiffServ network. Experiment 2 inspects the impact to the in DiffServ network when different type of traffic classes gradually overloads. As a result, DiffServ indeed improves the network QoS level by depressing lower priority services to enhance higher priority services. Key words: QoS, DiffServ 1. 來烈路刺量路流了路數路 All-IP 路 circuit switching 路 IP All-IP 路了 Alll-IP 路路 (QoS) All-IP 路 [1, 2] 不路不不 e-mailftp 路 (interactive) VoIP 了路 All-IP 路路 IETF 類路 Differentiated Service, DiffServ[3] 料數 NS-2 路 [4, 5] 不行兩不路料流 (traffic) DiffServ Best-Efforts QoS NSC 91-2219-E-004-002

DiffServ BE QoS 不料流 DiffServ assured forward service class DiffServ 料流度 1.1 1.1.1 UMTS 料流類 All-IP 路 (delay time)(jitter) ()DiffServ 不料流類不 UMTS(Universal Mobile Telecommunications System) 路行略類 [6](conversational class) 串流 (streaming class)(interactive class)(background class) (FTP) 1.1 類度 1.1.2 DiffServ 了料流不 IEFT 了 Differentiated Services, DiffServQoS 路路便類類 (DSCP, DiffServ Code Point) 路路類行諾 1.2 DiffServ Source DiffServ Destination DiffServ Ingress 便行類路便類 Egress 1.1 料流度來類類 300ms 例路串流度料料 (data communication) 兩類度更 (telnet) 料 1.2DiffServ IETF 了 1. EF, Expedited Forwarding[7] 類 (delay time) 來例路類 Guaranteed Service 2. AF, Assured Forwarding[8] EF BE AF 不若路塞 3. 力 BE, Best-Effort Forwarding[9]

IP 路 BE 律不 BE IP Precedence 留 1.1.3 NS-2 NS-2Network Simulator Version 2[4,5] 來路路路路路路 2. 2.1 Traffic Workload Modeling 料流路來 voice over IP 串流 video on demand telnet FTP 了料流路料流料流類 VoIP: on/off Markov process 來 1/β 1/α 數數數 X 度數 f X ax ae x > 0; a > 0 ( x) = where 0 otherwise E[X]=1/a and var[x]=1/ a 2 on state 率 α α + β ITU-T Recommendation P. 59[10] 1/β 1/α 1.004 1.587 on state ( ) 率 R 料 off state ( ) 不料裡 VoIP codec ITU-T G.729 CS-ACELP[11] R 8 Kbps voice data 20 bytes VOD: CBR (constant bit rate) VOD 率 384 Kbps 210 bytes Telnet: NS-2 telnet traffic generator[4] 流量 1000 byte 率 15.52 Kbps FTP: NS-2 FTP traffic generator[4] 流量 1000 byte 率 3434.77 Kbps 流量來流量來了路 traffic NS-2 [4] Pareto on/off 來 Pareto 度數 f ab x a ( x) = a + 1 for x b a shape parameter 裡 1.5 b scale parameter 5 ms 2.2 DiffServ vs. Best-Effort 料流量 UMTS 料流路 1-11-21-3 1-4 流量流量 DiffServ BE 兩 QoS 理料流路 2.1 路 agent src0src1 n0 10 Mbps, 2 ms 連 (duplex link)n0 n1 n1 dst 連

5 Mbps, 10 ms 連 src0 流量 agent 料 dst null agent 裡 null agent 料不流量 src1 料流 var 不料流 var 料 dst sink agentsink agent 料流類若 TCP ACK 若 UDP 不路拓 BE DiffServDiffServ QoS QoS 路 2-9Mb 路流量 var 2.1 路拓 Null sink 令兩路路流量 2 9Mbpsvar 不流量量料流路 var DiffServ Best-Effort 兩 QoS 行流量兩 QoS var 來 DiffServ src0 dst src1 dst 量 n0 列來 TCP 量 2.3 DiffServ vs. 料流立路料流量 DiffServ 立路類都 QoS 若類料流量 2.1 2.1 流量 2-1 VoIP 2-2 VOD 2-3 Telnet 2-4 FTP 路 2.2e1coree2 DiffServ e1 e2 路 core 路 s1 s2s3 s4 料 dest 料 DiffServ 連 10Mbps DiffServ core e2 7Mbpse1 core 1.5Mbps Weight Round Robin s1s2 s3s4 數例 440.11.9 e1 core e1 core EXP UDP CBR UDP TELN TCP FTP TCP s1 s2 10Mb,2ms 10Mb,2ms s3 s4 10Mb,2ms 10Mb,2ms null null 1.5Mb,50ms 7Mb,50ms 10Mb,5ms e1 core e2 dest 6Mb,50ms 6Mb,50ms sink sink Core network 2.2 路 VoIP s1 流 VOD s2 流 telnet s3 流兩 FTP s4 流 e1 core 路率料流流量率不 e1 列 n1 列來

率 3. 3.1 DiffServ vs. Best-Effort 3.1 流量流量 5Mbps BE 路 DiffServ 不流量流量 5Mbps 便路流量 DiffServ BE 路 3.2 量 DiffServ 量 BE 路路流量 delay time 路流量 (Mbps) 3-1 流量路流量路流量 (Mbps) 3-2 流量量 1-1DiffServ VoIP 料流率 8 Kbps 流量 5Mbps 惡 3.3 流量 5Mbps DiffServ BE 路 3.4 流量量 DiffServ BE 路不 3.5 VoIP 料流兩 QoS 5 Mbps VoIP BE 路 DiffServ 3.6 VoIP 料流量路路流量 Delay (with VoIP) delay time 路流量 (Mbps) 3.3 1-1 流量路流量 (with VoIP) 路路流量 (Mbps) 3-4 1-1 流量量 VoIP Delay 路路流量 3-5 1-1 VoIP

VoIP 路路流量 (Mbps) 3-6 1-1 VoIP 量 DiffServ 流量 VoIP 1-2DiffServ 串流 3.7 流量 4 Mbps 流量兩路 4 Mbps 流量 DiffServ BE 路度 3-8 流量兩 QoS 量流量量 DiffServ BE 路路流量 Delay (with VOD) average delay(s) 路路流量 (Mbps) 3-7 1-2 流量路流量路路流量 (Mbps) 3-8 1-2 流量量 3-9 VOD 流量 4Mbps VOD 量 4Mbps VOD DiffServ 量不 BE 路 3-10 VOD 量 DiffServ VOD BE 路 DiffServ 流量 VOD average delay(s) VOD Delay 路路流量 (Mbps) 3.9 1-2 VOD VOD 路路流量 (Mbps) 3.10 1-2 VOD 1-3DiffServ 流量 5 Mbps 3.11 兩 QoS 都 5 Mbps 7 Mbps 兩都異不 7 Mbps DiffServ 流量 3.12 列了量流量量 DiffServ BE 不 3.13 流量 5 Mbps

BE telnet 料流 DiffServ telnet 不兩 QoS telnet 路流量 average delay(s) 路路流量 (Mbps) 3.11 1-3 流量路流量 average delay(s) 路路流量 (Mbps) 3.12 1-3 流量量 Telnet Delay 路流量 (Mbps) 3.13 1-3 telnet 路 1-4DiffServ 3.14 流量 5Mbps DiffServ BE 3.15 兩流量量不路流量 delay time(s) 路流量 (Mbps) 3.14 1-4 流量路流量 FTP Delay 路流量 (Mbps) 3.15 1-4 流量量 Best-Effort DiffServ 路流量 (Mbps) 3.16 1-4 FTP 路 3.16 BE FTP 料流流量不不 0.04 DiffServ DiffServ 度理 FTP 不量 FTP 不 3.17 BE DiffServ 裡 FTP throughput 流量率 3.18

流量 throughput BE DiffServ 裡 throughput 率理 DiffServ FTP 不 throughput thoughput(kbyte/s) FTP Throughput 路路流量 (Mbps) 3.17 1-4 FTP Throughput 路流量路路流量 (Mbps) 3.18 1-4 流量 Throughput 3.2 DiffServ vs. 料流 3.19 料流都 3.21 VoIP VoIP 率 VoIP 率 VoIPFTP 率零 VOD telnet 不 VoIP 率料流 delay time(sec.) rate VoIP 料流數量 3.20 VoIP 料流 loss rate VoIP 料流數量 3.21 VoIP 率 3.19 2-1DiffServ 度 2-1 率 3.20 delay time(sec.) 料流 delay time VOD 料流數量 3.22 VOD

2-2DiffServ 串流度 2-2 率 3.22 3.23VOD 率 VOD 0.14 率 80%FTP 率料流 VOD telnet 率零料流 delay time delay time(sec.) 料流 loss rate rate telnet 料流數量 3.24 telnet VOD 料流數量 3.23 VOD 率 2-3DiffServ 度 2-3 率零 3.24FTP VODtelnet FTP 不 3.25 VoIPVOD telnet telnet telnet VoIP VOD 都料流 delay time delay time(sec.) telnet 料流數量 3.25 telnet 2-4DiffServ 度 2-4 率 3.26 3.27FTP 率 8 FTP 率 0.3% 1 VoIPVOD telnet 3.28 FTP VoIP VOD telnet 料流 delay time FTP 料流數量 3.26 FTP 料流 loss rate FTP 料流數量 3.27 FTP 率

料 delay time(sec.) FTP 料流數量 3.28 FTP 4. 論來 4.1 論 DiffServ 路 QoS 流量流量降 DiffServ 度度度度論類料流類料流類料流 FTP 都 FTP 了 FTP 料流不不料流類率不 FTP telnet VoIP VOD 兩流量不 VoIP VOD 流量 4.2 來路拓不路若拓度更料流不料流都數 model 路 QoS DiffServ 參料 [1] Xiao, X., L. -M. Ni, Internet QoS: A Big Picture, IEEE Network, 13(2):8-18, March-April 1999. [2] Miras, D., Network QoS Needs of Advanced Internet Applications, Internet2 - QoS Working Group, November 2002. [3] Blake, S, D. Black, M. Carlson, E. Davies, Z. Wang, W. Weiss, An Architecture for Differentiated Services, RFC 2475, December 1998. [4] Fall, K., K. Varadhan, The ns Manual, http://www.isi.edu/nsnam/ns/, April 2002. [5] Pieda, P., J. Ethridge, M. Baines, F. Shallwani, A Network Simulator Differentiated Services Implementation, Open IP, Nortel Networks, 2000. [6],, QoS Challenges in Third Generation Mobile Networks, in: Proceedings of 2001 National Computer Syposium, December 2001. [7] Jacobson, V., K. Nichols, K. Poduri, An Expedited Forwarding PHB, RFC 2598, June 1999. [8] Heinanen, J., F. Baker, W. Weiss, and J. Wroclawski, Assured Forwarding PHB Group, RFC 2597, June 1999. [9] Clark, D., W. Fang, Explicit Allocation of Best Effort packet Delivery Service, IEEE/ACM Transactions on Networking, 6(4):364-373, August 1998. [10] International Telecommunication Union,

Artificial Conversational Speech, ITU-T Recommendation P.59, March 1993. [11] International Telecommunication Union, 8 kbit/s CS-ACELP speech coder, ITU-T Recommendation G.729 Annex C, September 1998.