# AWS KMS internal operations
<a name="kms-internals"></a>

AWS KMS internals are required to scale and secure HSMs for a globally distributed key management service.

**Topics**
+ [Domains and domain state](domains-and-domain-state.md)
+ [Internal communication security](internal-communication-security.md)
+ [Replication process for multi-Region keys](replicate-key-details.md)
+ [Durability protection](durability-protection.md)