The applications and software using cloud computing as a base have significantly increased, and cloud computing is nowadays developed as a scalable and cost-effective technique. It facilitates many features in the computing environment like resource pooling, multi-tenancy, virtualization, etc. The cloud environment has led to the proliferation of various attacks that affect the security of applications and software developed by using cloud services and also cloud user's data. Data security is the main concern in cloud computing because it is stored in data centers provided by service providers. The chapter presents the background history of cloud computing and different challenges faced by the cloud environment, especially in terms of providing security for customer data stored in data centers. Authors also discuss the case studies on Microsoft Azure (i.e. a cloud platform) and Aneka (i.e. a cloud development and management platform).
Top1. Cloud Computing
Cloud computing is defined as “a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction”, according to National Institute of Standards and Technology (NIST) (Mell & Grance, 2011). On the other hand, cloud computing provides services without the installation of software and infrastructure on the user's own system, eliminating maintenance overhead that automatically reduces overall costs and improves system performance. Entities using cloud services are known as 'cloud users'; Including mobile devices, tablets, thin and thick clients such as computers, servers, web browsers, etc., and organizations that provide cloud-related services and provide solutions on demand to consumers, are known as cloud service providers (CSPs) (Hayes, 2008; Zhu et al., 2011; Furht, & Escalante, 2010; Rimal, Choi & Lumb, 2010; Gou, Yamaguchi & Gupta, 2017; Gupta, Agrawal & Yamaguchi, 2016; Gupta, 2019; Joshi & Gupta, 2019). Figure 1 depicts architecture of cloud computing environment.
Figure 1. Cloud Computing Architecture
Top2. Motivation
Nowadays cloud computing has become popular and its domain has expanded. Figure 2 shows the trend of adopting the cloud services world-wide in year 2019 and the estimated statistics for the year 2020. It clearly shows that cloud adoption is rapidly growing and it has many advantages for both customers and providers, but it also faces many security challenges. The public cloud computing market grows rapidly, including infrastructure, platform, software and business processes delivered in the form of a service. The public cloud market was $ 146 billion in 2017 and $ 178 billion in 2018. It’s estimated worth is $ 208 billion for year 2019 and $ 236 billion for year 2020. Global market growth of cloud computing is shown in figure 3.
Cloud computing is actively evolving and, therefore, has many vulnerabilities that can be exploited by malicious insiders or cyber criminals. Some of them are shared technology, weak cryptography, provider lock-in, vulnerable cloud services, malicious insiders etc. The primary purpose of cyber attackers is to prevent access to cloud services for legitimate users and to gain access to user data. This causes cloud users to lose confidence in cloud services and cloud users suffer heavy losses (Stergiou, Psannis, Gupta & Ishibashi, 2018; B. B. Gupta., S. Gupta & Chaudhary, 2017; Gupta (Ed.), 2018; Li, Z. Zhang & L. Zhang, 2018; Gupta & Badve, 2017).
Figure 2. World-wide usages of cloud services
Figure 3.Global market growth of cloud computing