Cloud Service Providers, such as Google Cloud Platform, Microsoft Azure, or Amazon Web Services, offer continuously evolving cloud services. It is a growing industry. Businesses, such as Netflix and PayPal, rely on the Cloud for data storage, computing power, and other services. For businesses, the cloud reduces costs, provides flexibility, and allows for growth. However, there are security and privacy concerns regarding the Cloud. Because Cloud services are accessed through the internet, hackers and attackers could possibly access the servers from anywhere. To protect data in the Cloud, it should be encrypted before it is uploaded, it should be protected in storage and also in transit. On the other hand, data owners may need to access their encrypted data. It may also need to be altered, updated, deleted, read, searched, or shared with others. If data is decrypted in the Cloud, sensitive data is exposed and could be exposed and misused. One solution is to leave the data in its encrypted form and use Searchable Encryption (SE) which operates on encrypted data. The functionality of SE has improved since its inception and research continues to explore ways to improve SE. This paper reviews the functionality of Searchable Encryption, mostly related to Cloud services, in the years 2019 to 2023, and evaluates one of its schemes, Fully Homomorphic Encryption. Overall, it seems that research is at the point where SE efficiency is increased as multiple functionalities are aggregated and tested.

翻译：谷歌云平台、微软Azure或亚马逊网络服务等云服务提供商不断推出演进中的云服务。这是一个持续增长的行业。Netflix和PayPal等企业依赖云服务进行数据存储、计算能力获取及其他服务。对这类企业而言，云计算能够降低成本、提供灵活性并支持业务扩展。然而，云计算存在安全与隐私方面的隐忧。由于云服务通过互联网访问，黑客和攻击者可能从任何地点入侵服务器。为保护云端数据，数据在上传前应进行加密，在存储和传输过程中亦需受保护。另一方面，数据所有者可能需要访问其加密数据，或需要对数据进行修改、更新、删除、读取、搜索及与他人共享。若数据在云端被解密，敏感数据将暴露并可能被滥用。解决方案之一是保持数据的加密状态，并采用可搜索加密（SE）技术对加密数据直接操作。自可搜索加密诞生以来，其功能不断完善，相关研究持续探索改进方法。本文综述了2019至2023年间可搜索加密（主要涉及云服务）的功能特性，并对其一种方案——全同态加密——进行了评估。总体而言，研究已进入通过集成并测试多重功能来提高可搜索加密效率的阶段。