Three layers, three responsibilities
Logical tenant isolation scopes queries and actions to an organisation. A Data Encryption Key (DEK) encrypts content. A Key Encryption Key (KEK) protects the data key in turn. This is often called envelope encryption.
Tenant-specific DEKs can limit the impact of a compromised key. They do not replace authorisation: a service with access to several keys must still assign every request to the correct tenant.
Rotation is a process, not a switch
Rotation requires a decision about the key version used for new writes and how older content remains readable. Depending on the architecture, data keys are rewrapped or the data itself is re-encrypted. Backups, retries and recovery belong in the plan.
Regular changes without an inventory can make data unreadable. NIST therefore treats key management as a lifecycle: generation, distribution, use, backup, replacement and secure retirement.
What this means for AI Link
AI Link isolates organisation access and uses AES-256-GCM for stored secrets. This is not equivalent to automatic rotation of individual tenant keys. The DEK/KEK architecture explained here is a security concept, not a claim that individual key management is already available.
Requirements for dedicated keys, hardware security modules or customer-managed keys are addressed in the deployment architecture. The documented service scope for the environment establishes what is provided.
Sources & further reading
Original research, provider documentation and further reading on the concepts and figures discussed here.