What is a scatter-gather router?

A scatter-gather router is a routing strategy that sends a single message to multiple routes simultaneously. This approach allows for concurrent processing of data by distributing the same input message across different endpoints or services. Each route processes the message independently and can return responses that can later be aggregated if needed.

This method is particularly useful in scenarios where you need to make parallel calls to several APIs or services to gather comprehensive data quickly. By sending the same message to multiple destinations at once, the overall time taken to receive different pieces of data is reduced, improving performance and efficiency.

The other options describe different concepts: synchronizing multiple API calls implies a coordination of requests rather than sending them out simultaneously; merging responses relates to composing a single coherent output from multiple sources, which can occur after the scatter-gather process; and load balancing is focused on distributing requests evenly across multiple services to optimize resource use, but it does not capture the essence of sending the same message to multiple routes at once.