The recent years have witnessed significant interest in migrating different applications into the cloud platforms. In this context, one of the main challenges for cloud applications providers is how to ensure high availability of the delivered applications while meeting users’ QoS. In this respect, replication techniques are commonly applied to efficiently handle this issue. From the literature, according to the used granularity for replication there are two major approaches to achieve replication: either through replicating the service or the underlying data. The latter one is also known as Data-oriented Replication (DoR), while the former one is referred to as Service-oriented Replication (SoR). DoR is discussed extensively in the available literature and several surveys are already published. However, SoR is still at its infancy and there is a lack of research studies. Hence, in this paper we present a comprehensive survey of SoR strategies in cloud computing. We propose a classification of existing works based on the research methods they use. Then, we carried out an in-depth study and analysis of these works. In addition, a tabular representation of all relevant features is presented to facilitate the comparison of SoR techniques and the proposal of new enhanced strategies.

近年来，目睹了将不同的应用程序迁移到云平台的巨大兴趣。在这种情况下，云应用程序提供商面临的主要挑战之一是如何确保交付的应用程序的高可用性同时满足用户的QoS。在这方面，复制技术通常用于有效处理此问题。根据文献，根据所使用的复制粒度，可以通过两种主要方法来实现复制：通过复制服务或基础数据。后一种也称为面向数据的复制（DoR），而前一种称为面向服务的复制（SoR）。在现有文献中对DoR进行了广泛讨论，并且已经发布了一些调查。然而，SoR仍处于起步阶段，缺乏研究研究。因此，在本文中，我们对云计算中的SoR策略进行了全面的调查。我们建议根据现有研究方法对现有作品进行分类。然后，我们对这些作品进行了深入的研究和分析。此外，还提供了所有相关功能的表格表示形式，以帮助比较SoR技术和提出新的增强策略。