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On the challenge and design of transport protocols for MMORPGs

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Abstract

Although MMORPGs are becoming increasingly popular as well as a highly profitable Internet business, there is still a fundamental design question: Which transport protocol should be used—TCP, UDP, or some other protocol? In this paper, we first evaluate whether TCP is suitable for MMORPGs, and then propose some novel transport strategies for this genre of games. Our analysis of a trace collected from a TCP-based MMORPG called ShenZhou Online indicates that TCP is unwieldy and inappropriate for MMORPGs. We find that the degraded network performance problems are due to the following characteristics of MMORPG traffic: 1) tiny packets, 2) a low packet rate, 3) application-limited traffic generation, and 4) bi-directional traffic. Since not all game packets require reliable transmission or in-order delivery, transmitting all packets with a strict delivery guarantee causes high delays and delay jitters. Therefore, our proposed transport strategies assign game packets with appropriate levels of transmission guarantee depending on the requirements of the packets’ contents. To compare the performance of our approach with that of existing transport protocols, we conduct network simulations with a real-life game trace from Angel’s Love. The results demonstrate that our strategies significantly reduce the end-to-end delay and delay jitter of packet delivery. Finally, we show that our strategies effectively raise satisfaction levels of the game players.

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References

  1. Allman M, Paxson V, Stevens W (1999) TCP congestion control. RFC 2581

  2. Braden R (1989) Requirements for internet hosts—communication layers. RFC 1122

  3. Chen K-T, Huang P, Lei C-L (2006) Game traffic analysis: an MMORPG perspective. Comput Networks 50(16):3002–3023

    Article  Google Scholar 

  4. Chen K-T, Huang P, Lei C-L (2006) How sensitive are online gamers to network quality? Commun ACM 49(11):34–38

    Article  Google Scholar 

  5. Chen K-T, Huang P, Lei C-L (2009) Effect of network quality on player departure behavior in online games. IEEE Trans Parallel Distrib Syst 20(5):593–606

    Article  Google Scholar 

  6. Claypool M (2005) The effect of latency on user performance in real-time strategy games. Comput Networks 49(1):52–70 (special issue on Networking Issues in Entertainment Computing)

    Article  Google Scholar 

  7. Claypool M, Claypool K (2006) Latency and player actions in online games. Commun ACM 49(11):40–45

    Article  Google Scholar 

  8. ENet (2008) ENet: an UDP networking layer for the multiplayer first person shooter cube. http://enet.cubik.org/

  9. Floyd S, Kohler E (2006) Profile for datagram congestion control protocol (DCCP) congestion control ID 2: TCP-like congestion control. RFC 4341

  10. Floyd S, Kohler E, Padhye J (2006) Profile for datagram congestion control protocol (DCCP) congestion control ID 3: Tcp-friendly rate control (TFRC). RFC 4342

  11. GameDev.Net (2004) FAQ—multiplayer and network programming. http://www.gamedev.net/

  12. Griwodz C, Halvorsen P (2006) The fun of using TCP for an MMORPG. In: NOSSDAV ’06: proceedings of the 2006 international workshop on Network and operating systems support for digital audio and video, pp 1–7

  13. Harcsik S, Petlund A, Griwodz C, Halvorsen P (2007) Latency evaluation of networking mechanisms for game traffic. In: NetGames ’07: proceedings of the 6th ACM SIGCOMM workshop on network and system support for games, pp 129–134

  14. Kohler E, Handley M, Floyd S (2006) Datagram congestion control protocol (DCCP). RFC 4340

  15. Mathis M, Mahdavi J, Floyd S, Romanow A (1996) TCP selective acknowledgement options. RFC 2018

  16. OpenTNL (2004) The Torque network library. GarageGames. http://www.opentnl.org/

  17. Pack S, Hong E, Choi Y, Park I, Kim J-S, Ko D (2002) Game transport protocol: lightweight reliable transport protocol for massive interactive on-line game. In: Proceedings of the SPIE, vol. 4861. pp 83–94

  18. Shirmohammadi S, Georganas ND (2001) An end-to-end communication architecture for collaborative virtual environments. Comput Networks 35(2–3):351–367

    Article  Google Scholar 

  19. Stevens RW (1995) TCP/IP Illustrated, vol 2: the implementation. Addison-Wesley, Reading

    Google Scholar 

  20. Stewart R (2007) Stream control transmission protocol. RFC 4960

  21. UserJoy Technology (2007) ShenZhou Online. http://www.ewsoft.com.tw/

  22. Woodcock BS (2008) An analysis of MMOG subscription growth—version 23.0. http://www.mmogchart.com/

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Acknowledgements

The authors would like to thank the anonymous reviewers for their helpful comments. This work was supported in part by Taiwan Information Security Center (TWISC), National Science Council under the grants NSC97-2219-E-001-001 and NSC97-2219-E-011-006. It was also supported in part by the National Science Council of Taiwan under the grants NSC96-2628-E-001-027-MY3 and NSC97-2221-E-001-009.

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Authors and Affiliations

  1. Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan

    Chen-Chi Wu, Chih-Ming Chen, Polly Huang & Chin-Laung Lei

  2. Institute of Information Science, Academia Sinica, No. 128, Sec. 2, Academia Rd., Nankang District, Taipei, 115, Taiwan

    Kuan-Ta Chen

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  1. Chen-Chi Wu
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  2. Kuan-Ta Chen
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  3. Chih-Ming Chen
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  5. Chin-Laung Lei
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Correspondence to Kuan-Ta Chen.

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Wu, CC., Chen, KT., Chen, CM. et al. On the challenge and design of transport protocols for MMORPGs. Multimed Tools Appl 45, 7–32 (2009). https://doi.org/10.1007/s11042-009-0297-5

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  • DOI: https://doi.org/10.1007/s11042-009-0297-5

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