We consider a wireless communication system with a passive eavesdropper, in which a transmitter and legitimate receiver generate and use key bits to secure the transmission of their data. These bits are added to and used from a pool of available key bits. In this work, we analyze the reliability of the system in terms of the probability that the budget of available key bits will be exhausted. In addition, we investigate the latency before a transmission can take place. Since security, reliability, and latency are three important metrics for modern communication systems, it is of great interest to jointly analyze them in relation to the system parameters. In particular, we show under what conditions the system may remain in an active state indefinitely, i.e., never run out of available secret-key bits. The results presented in this work will allow system designers to adjust the system parameters in such a way that the requirements of the application in terms of both reliability and latency are met.

翻译：我们考虑一个存在被动窃听者的无线通信系统，其中发射机和合法接收机生成并使用密钥比特来确保数据传输的安全性。这些比特被添加至可用密钥比特池中，并从该池中消耗使用。本文从可用密钥比特预算耗尽的概率角度分析了系统的可靠性。此外，我们研究了传输发生前的时延特性。由于安全性、可靠性和时延是现代通信系统的三个重要指标，因此联合分析它们与系统参数之间的关系具有重要意义。特别地，我们揭示了系统能够无限期维持活动状态（即永不耗尽可用密钥比特）的条件。本文所提出的研究结果将使系统设计者能够调整系统参数，从而满足应用在可靠性和时延两方面的要求。