Name
Abstract | ||
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Online gaming is one of the most profitable busi- nesses on the Internet. Among various threats to continuous player subscriptions, network lags are particularly notorious. It is widely known that frequent and long lags frustrate game players, but whether the players actually take action and leave a game is unclear. Motivated to answer this question, we apply survival analysis to a 1,356-million-packet trace from a sizeable MMORPG, called ShenZhou Online. We find that both network delay and network loss significantly affect a player's willingness to continue a game. For ShenZhou Online, the degrees of player "intolerance" of minimum RTT, RTT jitter, client loss rate, and server loss rate are in the proportion of 1:2:11:6. This indicates that 1) while many network games provide "ping time," i.e., the RTT, to players to facilitate server selection, it would be more useful to provide information about delay jitters; and 2) players are much less tolerant of network loss than delay. This is due to the game designer's decision to transfer data in TCP, where packet loss not only results in additional packet delays due to in-order delivery and retransmission, but also a lower sending rate. FPS (First-Person Shooting) games, RTS (Real Time Strategy) games, sports games, and car racing games (2, 3, 11, 13, 16- 18) (cf. Section II-A). MMORPGs are different in that there are no explicit victories or defeats, scores, or rankings, and the playing time is a more appropriate indicator of the player's gaming experience. Therefore, in this attempt to understand MMORPG players' QoS-sensitivity, we ask the question: "Once a player is in a game, how does network QoS affect his decision to continue or leave the game?" This work is, as far as we know, the first quantitative analysis on the relationship between network QoS and online game playing times. In this paper, we analyze the lifetimes of game sessions derived from ShenZhou Online (20), a commercial MMORPG. Using a survival analysis approach, we investigate the relation- ship between network QoS and session times. Although, logi- cally, the relation of cause and effect cannot be clarified from a cross-sectional study, we assume the correlation between game session times and network QoS implies that premature departures are caused by unfavorable network experience. The major findings are as follows. First, we show that both network delay and network loss significantly affect players' willingness to continue a game or leave it, whereas earlier studies indicate that players have remarkable tolerance of unfavorable network conditions (3, 11, 18). Second, while many network games provide "ping time," i.e. the round trip time (RTT), to players to facilitate server selection, we show that the delay jitters are more important than absolute delays in terms of playing time. Therefore, in addition to the "ping time," its variations should also be considered in the server selection process. Third, quantitatively, the degrees of player "intolerance" to minimum RTT, RTT jitter, client loss rate, and server loss rate are in the proportion of 1:2:11:6. To be specific, a player's decision to leave a game due to unfavorable network conditions is based on the following levels of intolerance: client packet loss (55%), server packet loss (30%), RTT fluctuations (10%), and minimum RTT (5%). While most QoS- sensitivity studies focus on the impact of delay, we argue that delay jitters and the packet loss (error) rate are more important, since, from our modeling, absolute delay times only contribute 1/20 of the influence on average to the QoS- intolerance of MMORPG players. Furthermore, we believe |
Year | DOI | Venue |
|---|---|---|
2006 | 10.1109/INFOCOM.2006.286 | INFOCOM |
Keywords | Field | DocType |
index terms— human factors,internet measurement,quality of service,net- work games,survival analysis,cross sectional study,round trip time,profitability,information science,network delay,human factors,jitter,disruption tolerant networking,quantitative analysis,packet loss,indexing terms,error rate | Network delay,Ping (video games),Video game design,Computer science,Retransmission,Network packet,Packet loss,Computer network,Quality of service,The Internet | Conference |
ISSN | ISBN | Citations |
0743-166X | 1-4244-0221-2 | 36 |
PageRank | References | Authors |
2.74 | 9 | 5 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Kuan-Ta Chen | 1 | 1896 | 136.86 |
| Polly Huang | 2 | 371 | 34.65 |
| Guo-shiuan Wang | 3 | 36 | 2.74 |
| Chun-Ying Huang | 4 | 589 | 39.51 |
| Chin-Laung Lei | 5 | 1686 | 201.07 |