Allow BYOK for data collection

Thanks for the submission and context. At this stage - we don't have any plans to implement BYK but we will continue to monitor the votes/inputs on this submission and evaluate accordingly!

Copy from dicussions why BYOK (with CMK) is important vs. just Apptio managed key:

Prospect looking for CMK with IBM Cloudability.

We do not agree with the argument that the use of CMK significantly increases overhead and causes latency issues.

The underlying technology is the AWS native AWS KMS key store and:

• AWS KMS uses envelope encryption: data keys are used to encrypt/decrypt raw data (not CMKs), CMK is only used to encrypt(wrap)/decrypt(unwrap) data keys. Data keys can (and should) be cached, reducing the need to call back to use CMKs. https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/data-key-caching.html , https://docs.aws.amazon.com/kms/latest/developerguide/kms-cryptography.html#enveloping. So you should cache data keys, not CMKs.
• CMKs stored by our AWS account can be generated in the same AWS region that matches the AWS region of Apptio further reducing latency. In addition multi-region keys are also available in AWS KMS to cover multiple AWS regions without the latency of cross-region call.

Please note that <prospect> has internal security requirements stating that data stored in cloud workloads must be encrypted using customer-managed data at rest encryption keys, CMKs.

Please download and review https://www.atlassian.com/whitepapers/cmk#download this whitepaper also mentions CMK performance  topics, including caching in detail. Atlassian products are heavily used by <prospect>.

This has been requested for Cloudability notably.