Challenge 2: Make globally unique IDs across distributed nodes. Sounds simple, but there are tradeoffs between uniqueness guarantees, performance, and coordination requirements.
Generates unique IDs without coordination between nodes
Uses node ID + timestamp + counter approach
Handles high-frequency ID generation within same millisecond
Simple but effective for most use cases
Combined three sources of uniqueness:
Node ID - Each node has a unique identifier
Timestamp - Millisecond precision
Counter - For multiple IDs within same millisecond
This gives us practical uniqueness without complex coordination protocols.
Pros:
No network coordination needed
Fast generation
Reasonably unique for most purposes
Cons:
Clock skew between nodes could theoretically cause collisions
Not cryptographically secure
Relies on node ID uniqueness
For this challenge, simple and fast beats perfect. Real systems might need UUIDs, Snowflake IDs, or other approaches depending on requirements.