Asynchronous message passing has the benefit of truly decoupling Microservices from each other. Since the communication is carried out by a broker, individual services need not be aware of the location of the receiver of the request. This also gives individual services the ability to scale independently and recover and respond to messages in case of failure. However, this communication pattern lacks the feature of immediate feedback and is slower than the synchronous communication format.

There are several tools available for such communication, such as MSMQ and Rabbit MQ. Microsoft Azure offers Service Bus Queues and Microsoft Azure Storage Queue for asynchronous messaging on cloud. Amazon SQS provides similar functionality in Amazon Web Services.