Hybrid Blockchain-Enabled Security in Cloud Storage Infrastructure …

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2.2

Cloud Computing Architecture

It is known that the cloud consists of three layers, which are SaaS, PaaS, and IaaS, so

each provider has its own infrastructure, platform, and software layer [2, 3], as shown

in Fig. 2. Thus, when the customer deals with the applications provided by the cloud

service provider, he is forced to use the infrastructure and platform that that provider

provides. Any breach or attack in IaaS will necessarily affect the security of the

other two layers and vice versa, therefore, the cloud service provider has full access

to customer data and knowledge of their location [4], which determines the level of

abstraction of each layer and the extent of user control, so IaaS has greater control

over the client, and control is decreasing towards the upper layers, which increases the

security risks in them and vice versa. Of course, each cloud service model has its own

security weaknesses in addition to the presence of common obstacles that have an

impact on all of them [5], and this increases the security dependency among them [6].

There are different types of attacks and threats that differ depending on the level

or the party. Various organizations such as the Cloud Security Alliance are working

on identifying security problems that need to be addressed [7].

Fig. 2 Architecture of cloud computing [5]