10.6Why async is more resilient

Suppose Salesforce is unavailable for 20 minutes.

Synchronous:

caller
 ↓
Mule
 ↓
Salesforce unavailable
 ↓
503

Every caller now needs its own retry strategy.

Async:

caller
 ↓
queue
 ↓
202

Worker:

attempt Salesforce
 ↓
fails
 ↓
retry later

The queue decouples:

request arrival

from:

downstream availability

That is a huge reliability benefit.