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International audienceIn multiplayer games, where many players take part in a game while communicating through a network, the players may have an inconsistent view of the game world because of the communication delays across the network. Consistency maintenance algorithms must be used to have a uniform view of the game world. The majority of these algorithms are used for wired network and they use a fixed approach which is hardly adaptable to the changing network and game environment. In these algorithms, an approach called locallag is used which delays the presentation of updates so as to account for network latencies. The value of local lag is usually fixed for a game session. In wireless networks where the network latencies can varies greatly, fixed local-lag approach can cause inconsistencies in the game state between different replicas. Also dead-reckoning is used along with local-lag to hide network latency and improve responsiveness. Keeping a fixed dead-reckoning approach in the face of changing network and game environment can produce unpredictable game behaviour which can cause human players to quit the game. In this paper, we present a dynamic and adaptable approach for local-lag and dead-reckoning in which the algorithm's parameters are changed according to the changing and unpredictable network and game environment. We believe that this adaptable approach can greatly improve consistency and hence the playability of the gam

A spoofing attack on a global navigation satellite system (GNSS) receiver is a threat to a significant community of GNSS users due to the high stakes involved. This paper investigates the use of slope based metrics for the detection of spoofing. The formulation of slope based metrics involves monitoring correlators along with tracking correlators in the receiver's channel, which are slaved to the prompt tracking correlator. In this study, using some candidate metrics, detectors have been formed through the analysis of simulated spoofing attacks. A theoretical variance of each metric has also been calculated as a reference for the threshold. A threshold is estimated using the measured variance from the clean signals, for specific false alarm rate. By using the measured threshold, detectors are formed based on slope metrics. These detectors have been tested using TEXBAT data. The results show that the differential slope metrics have good performance. The results have also been compared with some other techniques of spoofing detection.

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