Soru

A utility enterprise is designing a new cloud-based smart-grid monitoring platform. The system handles two primary data workloads. First, a time-series telemetry ingest workload receives smart meter readings at a rate of $100,000$ writes/second with sub-millisecond latency. Second, an online transaction processing (OLTP) workload manages customer billing and subscription metadata. The billing metadata requires a disaster recovery strategy with a Recovery Time Objective (RTO) of less than $15$ minutes and a Recovery Point Objective (RPO) of less than $5$ seconds across AWS regions. Additionally, weekly billing reports must be saved to object storage and securely shared with a third-party auditing AWS account. Encryption-at-rest is mandatory for these reports, and the primary account must maintain full control over the encryption key policy. Which database and storage architecture should a solutions architect design to satisfy these requirements with the lowest operational overhead?