Reactive defense mechanisms, such as intrusion detection systems, have made significant efforts to secure a system or network for the last several decades. However, the nature of reactive security mechanisms has limitations because potential attackers cannot be prevented in advance. We are facing a reality with the proliferation of persistent, advanced, intelligent attacks while defenders are often way behind attackers in taking appropriate actions to thwart potential attackers. The concept of moving target defense (MTD) has emerged as a proactive defense mechanism aiming to prevent attacks. In this work, we conducted a comprehensive, in-depth survey to discuss the following aspects of MTD: key roles, design principles, classifications, common attacks, key methodologies, important algorithms, metrics, evaluation methods, and application domains. We discuss the pros and cons of all aspects of MTD surveyed in this work. Lastly, we highlight insights and lessons learned from this study and suggest future work directions. The aim of this paper is to provide the overall trends of MTD research in terms of critical aspects of defense systems for researchers who seek to develop proactive, adaptive MTD mechanisms.

中文翻译：

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迈向主动、适应性防御：移动目标防御调查

在过去的几十年中，诸如入侵检测系统之类的反应性防御机制为保护系统或网络做出了重大努力。然而，反应式安全机制的本质是有局限性的，因为无法提前阻止潜在的攻击者。我们正面临着持续、先进、智能攻击激增的现实，而防御者在采取适当行动阻止潜在攻击者方面往往远远落后于攻击者。移动目标防御 (MTD) 的概念已成为一种旨在防止攻击的主动防御机制。在这项工作中，我们进行了全面、深入的调查，讨论了 MTD 的以下几个方面：关键角色、设计原则、分类、常见攻击、关键方法、重要算法、指标、评估方法和应用领域。我们讨论了这项工作中调查的 MTD 各个方面的利弊。最后，我们强调了从这项研究中吸取的见解和经验教训，并提出了未来的工作方向。本文的目的是为寻求开发主动、自适应 MTD 机制的研究人员提供防御系统关键方面 MTD 研究的总体趋势。