The study of optimal preemption policies for status update systems has been a recurring topic in the age of information (AoI) literature, where threshold-based structures have been shown to be optimal under a generate-at-will update generation model under certain assumptions. In this work, we study the effectiveness of threshold-based policies for a system with random update arrivals. In this regard, we introduce an analytical framework for evaluating the AoI of multi-threshold preemption policies and present interesting characteristics of the structure of the optimal preemption policy. We show the effectiveness of these threshold-based policies over the traditional probabilistic preemption policies and single-threshold policies, where we observe that significant gains in terms of AoI can be obtained by utilizing both the age of the packet and the age of the system when designing these preemption policies.

翻译：关于状态更新系统最优抢占策略的研究一直是信息年龄（AoI）文献中的反复出现主题，其中基于阈值的结构在特定假设下已被证明在即时生成更新模型下是最优的。本研究探讨了在随机更新到达系统中基于阈值策略的有效性。为此，我们引入了一个用于评估多阈值抢占策略信息年龄的分析框架，并揭示了最优抢占策略结构的有趣特征。我们展示了这些基于阈值的策略相比于传统概率抢占策略和单阈值策略的有效性，观察到在设计这些抢占策略时，通过同时利用数据包年龄和系统年龄可以获得显著的信息年龄增益。