中文摘要：

云用户只需投入很少的开销就能获得大量的计算资源和云存储空间，但云计算的资源共享特性也导致了许多安全方面的隐患，如为传播恶意程序提供了便利、用户隐私数据更易泄露、数据更易被破坏等。为保证云环境的健康发展，针对云犯罪展开取证分析（即云取证）显得尤为重要。对于云取证这一新兴领域，首先介绍了其概念以及当前该领域面临的技术、法律问题；重点介绍了目前云取证领域已经取得的研究成果；最后，比较分析了现有工作的优缺点并提出了云取证领域的机遇。

英文摘要：

Cloud users can get a lot of computer resources and storage space at low cost. However, the security risks, such as the spreading of illegal information, sensitive data leakage, data tampering, are still crucial problem in cloud computing envi- ronment. Hence, the forensics of cloud computing crime becomes particular important. Firstly, this paper introduced the con- cept of cloud forensics and listed the technical and legal challenges in could forensics. Then it introduced researches by now in cloud forensics and presented analysis summary on current researches. Finally, it put forward opportunities of cloud forensics.