Kuan-Ta Chen 1 , Yu-Chun Chang 12 , Po-Han Tseng 1 , Chun-Ying Huang 3 , and Chin-Laung Lei 2 1 Academia Sinica 2 National Taiwan University 3 National Taiwan Ocean University Measuring The Latency of Cloud Gaming Systems Conclusion We proposed a general methodology to measure the latency components of cloud gaming systems OnLive provides shorter latency for real-time gaming than SteamMyGame Future work Improve the proposed methodology Apply the methodology to more platforms and derive general guidelines for designing quality cloud gaming systems Cloud Gaming Motivation Game software becomes more complex The overhead of setting up a game is significant Games have software and hardware compatibility with computers Real-time game playing via thin clients Advantages of cloud gaming No set up overheads or compatibility issues People can play games anywhere, anytime Cloud gaming services OnLive, StreamMyGame, GAIKAI, G-cluster Global, OTOY, T5-Labs Which platform provides the best quality of service? Measurement Methodology Response delay : In each experiment, send ESC key in the game and see when the corresponding MENU frame will be displayed Response delay (RD) = Network delay (ND) + Processing delay (PD) + Playout delay (OD) Scatter Plot of t block_succeed and t block_failed Measurement Results How to determine the occurrence of t 3 Blocking is successful : add t block to the set t block_succeeded Blocking is failed : add t menu to the set t block_failed We then estimate t 3 as the point that yield the minimum sum of the two density functions formed by t block_succeeded and t block_failed Blocking : Block the incoming data on the client Blocking is successful Blocking is failed Experiment Setup • Game: Lego Batman: The VideoGame (Batman) Warhammer 40,000: Dawn of War (DOW) F.E.A.R. 2: Project Origin (FEAR) • Platform: OnLive (OnLive) StreamMyGame (SMG) Network delay (ND) = network RTT Processing delay (PD) = t 3 – t 0 – ND Playout delay (OD) = t 4 – t 3 t block t block +1 Time t menu Menu screen appears t block t block +1 Time t menu Internet LAN LAN Switch Client (Intel Core i7-920) Server (Intel Core i7-920) OnLive Server t 0 t 1 t 2 t 4 (controllable) t 3 (probable) (observable) Processing delay Playout delay Probing range Time Academia Sinica Server Client Game Servers PC Laptop Mobile Streaming Streaming Streaming Internet t 0 (Key event sent) t 1 (Key event received) t 2 (Frame sent) t 3 (Frame received) Menu frame Menu screen shown t 4 (Frame displayed)