Design a Distributed ID Generator

Functional Requirements:

• The system must generate globally unique 64-bit IDs.
• IDs should be time-sortable (IDs generated later have a higher value).
• The system should support high throughput for ID generation (e.g., thousands to millions of IDs per second).
• The ID generation should be distributed across multiple nodes to avoid a single point of failure.
• The API should be simple: clients request an ID and receive a unique 64-bit integer in response.

Non-Functional Requirements:

• High availability: The system should remain operational even if some nodes fail.
• Scalability: The system should be able to scale horizontally to handle increased load.
• Low latency: ID generation requests should be served quickly (ideally within a few milliseconds).
• Fault tolerance: The system should be resilient to individual node or network failures.
• No duplicate IDs: The system must guarantee uniqueness of IDs across all nodes and over time.