Criminal investigations are inherently complex as they typically involve interactions among various actors like investigators, prosecutors, and defendants. The pervasive integration of technology in daily life adds an extra layer of complexity, especially in crimes that involve a digital element. The establishment of digital forensics as a foundational discipline for extracting digital evidence further exacerbates the complex nature of criminal investigations, leading to the proliferation of multiple scenarios. Recognising the need to structure standard operating procedures for the handling of digital evidence, the representation of digital forensics as a protocol emerges as a valuable opportunity to identify security and privacy threats. In this paper, we delineate the protocols that compose digital forensics within a criminal case, formalise them as message sequence charts (MSCs), and identify their functional requirements.

翻译：刑事调查本质上具有复杂性，通常涉及调查人员、检察官和被告等不同角色之间的交互。技术在日常生活中的广泛渗透进一步增加了这种复杂性，尤其是在涉及数字元素的犯罪中。数字取证作为提取数字证据的基础学科的确立，进一步加剧了刑事调查的复杂性质，导致多种场景的涌现。鉴于规范数字证据处理标准操作程序的必要性，将数字取证表示为协议为识别安全与隐私威胁提供了宝贵的契机。本文在刑事案件背景下梳理构成数字取证的协议，将其形式化为消息序列图（MSCs），并识别其功能需求。