A number of papers have been proposed for the purpose of analyzing the traffic data of network game and providing the models recently. The traffic characteristics of network games are different according to the game genres, and the traffic is affected by player number and the in-game behaviors. In this paper, we develop the dedicated tool NetGame Sniffer for measurement and analysis of network game traffic, and measure the traffic of Quake and World of Warcraft. We analyze and compare the traffic characteristics according to the number of players and user actions, and propose the game traffic models and practical uses of the models. The analysis and models of network game traffic are can be used for effective network simulation, performance evaluation and the design of network games.