Explanation
Representational State Transfer (REST) uses TLS for communication over secured channels. Although REST also supports SSL, at this point SSL has been phased out due to vulnerabilities and has been replaced by TLS.

With PaaS providing a fully configured and managed framework, auto-scaling can be implemented to programmatically adjust resources based on the current demands of the environment.

No matter what form they come in, "services" are obtained or purchased by a cloud customer from a cloud service provider. Services can come in many forms--virtual machines, network configurations, hosting setups, and software access, just to name a few. Hosting and servers--or, with a cloud, more appropriately virtual machines--are just two examples of "services" that a customer would purchase from a cloud provider.
"Customers" would never be a service that's purchased.

Explanation/Reference:
Explanation:
The Russian government requires all data and processing of information about its citizens to be done solely on systems and applications that reside within the physical borders of the country. The United States, European Union, and Japan focus their data privacy laws on requirements and methods for the protection of data, rather than where the data physically resides.

Explanation
No matter what kind of application, system, or hosting model used, encryption is 100 percent dependent on encryption keys. Properly securing the keys and the exchange of them is the biggest and most important challenge of encryption systems.