Strategy-Proof Online Mechanisms for Weighted AoI Minimization in Edge Computing

Real-time information processing is critical to the success of diverse applications from many areas. Age of Information (AoI), as a new metric, has received considerable attention to evaluate the performance of real-time information processing systems. In recent years, edge computing is becoming an efficient paradigm to reduce the AoI and to provide the real-time services. Considering the substantial deployment cost and the resulting resource limitation in edge computing, a proper pricing mechanism is highly necessary to fully utilize edge resources and then minimize the overall AoI of the whole system. However, there are two challenges to design this mechanism: 1) the priorities (or values) of the real-time computing tasks, critical to the efficient resource allocation, are usually private information of users and may be manipulated by selfish users for their own interests; 2) due to the time-varying property of AoI, the values of the tasks discount with time, making the traditional pricing mechanisms infeasible. In this paper, we extend the classical Myerson Theorem to the online setting with time discounting tasks values, and accordingly propose an online auction mechanism, called PreDisc, including an allocation rule and a payment rule. We leverage dynamic programming to greedily allocate resources in each time slot, and charge the winning user with a new critical price, extended from the classical Myerson payment rule. A preemption factor is further employed to make a trade-off between the newly arrived tasks and ongoing tasks. We prove that PreDisc guarantees the economic property of strategy-proofness and achieves a constant competitive ratio. We conduct extensive simulations and the results demonstrate that PreDisc outperforms the traditional mechanisms, in terms of both weighted AoI and revenue of edge service providers. Compared with the optimal solution in offline VCG mechanism, PreDisc has much lower computation complexity with only a slight performance loss.