Security can't be an afterthought. It is essential in the multitenant environment of cloud.
It is clearly defined what the responsibility of AWS is as a service provider, and what the responsibility of a customer is as a consumer of AWS resources, and that helps to make the environment more secure.
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AWS is responsible for securing the cloud infrastructure while the customer is responsible for configuring security in the cloud.
The responsibility of AWS and a customer may change based on the cloud service model used by the customer.
Platform as a Service (PaaS) model demands more responsibility from AWS compared with Infrastructure as a Service (IaaS) because the customer has very little control over the overall environment in PaaS:
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As you go down in service model, customer...