The questionnaire provides some additional insights into AWS's security architecture. For example, AWS says it provides SOC Type II reports to customers to view under nondisclosure agreements. To prevent data leakage AWS uses software that isolates customer data in multi-tenant environments and prevents customers from accessing information not assigned to them. When a virtual machine instance is no longer needed by the customer, the decommissioning process is taken from the National Institutes of Standards in Technology (NIST) guidelines for erasing customer data. If that is not able to be done, the device can be degaussed or physically destroyed, AWS says in answering the questions.

The company says customers dictate where in the AWS cloud data is stored across various regions. The company also notes, however, that "AWS will not move customers' content from the selected Regions without notifying the customer unless required to comply with the law or requests of governmental entities." AWS says it is up to the customers to use their own encryption mechanisms if they so choose, but the company does offer -side encryption for its Simple Storage Service (S3) and virtual private cloud, which is a single-tenant offering.

As for testing of systems and whether the company conducts network or application-layer vulnerability assessments, AWS says that customers retain control of their guest operating systems, software and and therefore "are responsible for performing vulnerability scans and patching of their own systems," and adds later that customers can request permission to conduct scans of the cloud infrastructure assigned to them, so long as it does not impact other users' instances.

In addition to Amazon, -- which is owned by Verizon -- and each also submitted information for the STAR program.

The addition of the three cloud providers marks somewhat of a milestone for the program, as AWS is seen as a market-leading IaaS player in the cloud. CSA officials have said they expect additional providers to join the program in coming months. When the CSA announced STAR, it said big-name tech companies such as Google, Intel and McAfee had plans to join STAR, but they still have not.