We study the information freshness under three different source aware packet management policies in a status update system consisting of two independent sources and one server. The packets of each source are generated according to the Poisson process and the packets are served according to an exponentially distributed service time. We derive the average age of information (AoI) of each source using the stochastic hybrid systems (SHS) technique for each packet management policy. In Policy 1, the queue can contain at most two waiting packets at the same time (in addition to the packet under service), one packet of source 1 and one packet of source 2. When the server is busy at an arrival of a packet, the possible packet of the same source waiting in the queue (hence, source-aware) is replaced by the arrived fresh packet. In Policy 2, the system (i.e., the waiting queue and the server) can contain at most two packets, one from each source. When the server is busy at an arrival of a packet, the possible packet of the same source in the system is replaced by the fresh packet. Policy 3 is similar to Policy 2 but it does not permit preemption in service, i.e., while a packet is under service all new arrivals from the same source are blocked and cleared. Numerical results are provided to assess the fairness between sources and the sum average AoI of the proposed policies.

中文翻译：

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具有源感知数据包管理的多源系统中的平均 AoI

我们在由两个独立源和一个服务器组成的状态更新系统中研究了三种不同源感知数据包管理策略下的信息新鲜度。根据泊松过程生成每个源的数据包，并根据指数分布的服务时间为数据包提供服务。我们为每个数据包管理策略使用随机混合系统 (SHS) 技术推导出每个源的平均信息年龄 (AoI)。在策略1中，队列最多同时包含两个等待的数据包（除了正在服务的数据包），一个源1的数据包和一个源2的数据包。 当一个数据包到达服务器忙时，在队列中等待的相同源的可能数据包（因此，源感知）被到达的新数据包替换。在策略 2 中，系统（即 、等待队列和服务器）最多可以包含两个数据包，每个数据包一个。当一个数据包到达服务器繁忙时，系统中相同源的可能数据包被新数据包替换。策略 3 与策略 2 类似，但它不允许服务中的抢占，即，当一个数据包在服务中时，所有来自同一源的新到达都被阻止和清除。提供了数值结果以评估来源之间的公平性和拟议政策的总平均 AoI。当一个数据包正在服务时，所有来自同一来源的新到达的数据都会被阻止和清除。提供了数值结果以评估来源之间的公平性和拟议政策的总平均 AoI。当一个数据包正在服务时，所有来自同一来源的新到达的数据都会被阻止和清除。提供了数值结果以评估来源之间的公平性和拟议政策的总平均 AoI。