Time serves as the foundation of modern society and will continue to grow in value in the future world. Unlike previous research papers, authors delve into various time sources, ranging from atomic time and GPS time to quartz time. Specifically, we explore the time uncertainty associated with the four major Global Navigation Satellite Systems. Additionally, we provide a summary of eight metrics used to evaluate time accuracy. In existing time synchronization simulations provide partial usages. However, our research introduces a comprehensive and precise time synchronization simulation named P-TimeSync, leading to a better understanding of time synchronization in distributed environments. It is a state-of-the-art simulation tool for time because (1) it can simulate atomic clocks and quartz clocks with user-defined software clock algorithms, (2) the simulation provides nanosecond-level precision time across different network propagation paths and distances, (3) the tool offers a visualization platform with classic algorithms for distributed time synchronization, such as Cristian's algorithm and Berkeley algorithm, and (4) the simulation includes three time-sync attack functions, including distributed denial-of-service (DDoS) attack, IP spoofer, and router hijacker. The simulation easily allows for the redefinition of configurations and functions, supporting advanced research and development. The simulation tool could be downloaded via the website: https://github.com/rui5097/purdue_timesync

翻译：时间作为现代社会的基石，在未来世界中其价值将持续增长。不同于以往的研究论文，作者深入探讨了从原子时、GPS时到石英时的多种时间源。具体而言，我们探究了四大全球导航卫星系统伴随的时间不确定性。此外，我们总结了用于评估时间精度的八项指标。尽管现有的时间同步仿真提供了部分功能，但我们的研究提出了一种全面而精确的时间同步仿真——P-TimeSync，有助于更深入地理解分布式环境中的时间同步。这是一款先进的时间仿真工具，其优势在于：(1)能够通过用户定义的软件时钟算法仿真原子钟和石英钟；(2)可在不同网络传播路径和距离下提供纳秒级精度的时间；(3)该工具提供可视化平台，包含经典分布式时间同步算法（如Cristian算法和Berkeley算法）；(4)仿真包含三种时间同步攻击功能：分布式拒绝服务（DDoS）攻击、IP欺骗和路由器劫持。该仿真支持轻松重新定义配置和功能，可支撑高级研究与开发。该仿真工具可通过网站下载：https://github.com/rui5097/purdue_timesync