There are three, commonly accepted forms of Controls:
Administrative-These are the laws, regulations, policies, practices and guidelines that govern the overall requirements and controls for an Information Security or other operational risk program. For example, a law or regulation may require merchants and financial institutions to protect and implement controls for customer account data to prevent identity theft. The business, in order to comply with the law or regulation, may adopt policies and procedures laying out the internal requirements for protecting this data, which requirements are a form of control.
Logical -These are the virtual, application and technical controls (systems and software), such as firewalls, antivirus software, encryption and maker/checker application routines.
Physical -Whereas a firewall provides a "logical" key to obtain access to a network, a "physical" key to a door can be used to gain access to an office space or storage room. Other examples of physical controls are video surveillance systems, gates and barricades, the use of guards or other personnel to govern access to an office, and remote backup facilities.

Following are the characteristics of IaaS service model of cloud computing:
1. Scale
2. Converged network and IT capacity pool
3. Self-service and on-demand capacity
4. High reliability and resilience

This is a very confusing question and we need to understand that its a shared responsibility between cloud service provider and customer.

Indirect identifiers typically consist of demographic or socioeconomic information, dates, or events.
Although each standalone indirect identifier cannot identify the individual, the risk is that combining a number of indirect identifiers with external data can result in exposing the subject of the information.
For example, imagine a scenario in which users were able to combine search engine data, coupled with online streaming recommendations to tie back posts and recommendations to individual users on a website.