Biblio
Fog computing is a new computing paradigm that utilizes numerous mutually cooperating terminal devices or network edge devices to provide computing, storage, and communication services. Fog computing extends cloud computing services to the edge of the network, making up for the deficiencies of cloud computing in terms of location awareness, mobility support and latency. However, fog nodes are not active enough to perform tasks, and fog nodes recruited by cloud service providers cannot provide stable and continuous resources, which limits the development of fog computing. In the process of cloud service providers using the resources in the fog nodes to provide services to users, the cloud service providers and fog nodes are selfish and committed to maximizing their own payoffs. This situation makes it easy for the fog node to work negatively during the execution of the task. Limited by the low quality of resource provided by fog nodes, the payoff of cloud service providers has been severely affected. In response to this problem, an appropriate incentive mechanism needs to be established in the fog computing environment to solve the core problems faced by both cloud service providers and fog nodes in maximizing their respective utility, in order to achieve the incentive effect. Therefore, this paper proposes an incentive model based on repeated game, and designs a trigger strategy with credible threats, and obtains the conditions for incentive consistency. Under this condition, the fog node will be forced by the deterrence of the trigger strategy to voluntarily choose the strategy of actively executing the task, so as to avoid the loss of subsequent rewards when it is found to perform the task passively. Then, using evolutionary game theory to analyze the stability of the trigger strategy, it proves the dynamic validity of the incentive consistency condition.
While the Internet of Things (IoT) becomes increasingly popular and pervasive in everyday objects, IoT devices often remain unprotected and can be exploited to launch large-scale distributed denial-of-service (DDoS) attacks. One could attempt to employ traditional DDoS defense solutions, but these solutions are hardly suitable in IoT environments since they seldom consider the resource constraints of IoT devices. This paper presents FR-WARD which defends against DDoS attacks launched from an IoT network. FR-WARD is an adaptation of the classic DDoS defense system D-WARD. While both solutions are situated near the attack sources and drop packets to throttle DDoS traffic, FR-WARD utilizes the fast retransmit mechanism in TCP congestion control to minimize resource penalties on benign IoT devices. Based on our analysis and simulation results, FR-WARD not only effectively throttles DDoS traffic but also minimizes retransmission overhead for benign IoT devices.
In this paper, we propose ParaRegex, a novel approach for fast parallel regular expression matching. ParaRegex is a framework that implements data-parallel regular expression matching for deterministic finite automaton based methods. Experimental evaluation shows that ParaRegex produces a fast matching engine with speeds of up to 6 times compared to sequential implementations on a commodity 8-thread workstation.