Today is the era of the Internet of Things (IoT). The recent advances in hardware and information technology have accelerated the deployment of billions of interconnected, smart and adaptive devices in critical infrastructures like health, transportation, environmental control, and home automation. Transferring data over a network without requiring any kind of human-to-computer or human-to-human interaction, brings reliability and convenience to consumers, but also opens a new world of opportunity for intruders, and introduces a whole set of unique and complicated questions to the field of Digital Forensics. Although IoT data could be a rich source of evidence, forensics professionals cope with diverse problems, starting from the huge variety of IoT devices and non-standard formats, to the multi-tenant cloud infrastructure and the resulting multi-jurisdictional litigations. A further challenge is the end-to-end encryption which represents a trade-off between users’ right to privacy and the success of the forensics investigation. Due to its volatile nature, digital evidence has to be acquired and analyzed using validated tools and techniques that ensure the maintenance of the Chain of Custody. Therefore, the purpose of this paper is to identify and discuss the main issues involved in the complex process of IoT-based investigations, particularly all legal, privacy and cloud security challenges. Furthermore, this work provides an overview of the past and current theoretical models in the digital forensics science. Special attention is paid to frameworks that aim to extract data in a privacy-preserving manner or secure the evidence integrity using decentralized blockchain-based solutions. In addition, the present paper addresses the ongoing Forensics-as-a-Service (FaaS) paradigm, as well as some promising cross-cutting data reduction and forensics intelligence techniques. Finally, several other research trends and open issues are presented, with emphasis on the need for proactive Forensics Readiness strategies and generally agreed-upon standards.

中文翻译：

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物联网 (IoT) 取证调查：挑战、方法和未解决的问题

今天是物联网 (IoT) 时代。硬件和信息技术的最新进展加速了数十亿互连、智能和自适应设备在健康、交通、环境控制和家庭自动化等关键基础设施中的部署。通过网络传输数据，无需任何人机交互或人机交互，为消费者带来了可靠性和便利性，同时也为入侵者打开了一个新的机会世界，并引入了一整套独特而复杂的数字取证领域的问题。尽管物联网数据可能是一个丰富的证据来源，但取证专业人员应对各种各样的问题，从种类繁多的物联网设备和非标准格式开始，到多租户云基础设施和由此产生的多司法管辖区诉讼。另一个挑战是端到端加密，它代表了用户隐私权与取证调查成功之间的权衡。由于其易变性，必须使用经过验证的工具和技术来获取和分析数字证据，以确保监管链的维护。因此，本文的目的是确定和讨论基于 IoT 的复杂调查过程中涉及的主要问题，尤其是所有法律、隐私和云安全挑战。此外，这项工作概述了数字取证科学中过去和当前的理论模型。特别关注旨在以保护隐私的方式提取数据或使用基于去中心化区块链的解决方案保护证据完整性的框架。此外，本文还讨论了正在进行的取证即服务 (FaaS) 范式，以及一些有前景的跨领域数据缩减和取证情报技术。最后，介绍了其他一些研究趋势和未解决的问题，重点是对主动取证准备策略和普遍认可的标准的需求。