The image shows a diagram of an asynchronous interaction with a notification time occurring between a client BPEL process and a service BPEL process. The following actions take place:

1. The client BPEL process has a scope activity and an onAlarm handler. The scope activity contains an invoke activity to call a service, and a receive activity to wait for a callback.

2. The call service invoke activity sends a request to the service BPEL process, by way of a WSDL partner link.

3. The service BPEL process has a receive activity that receives the client's request, and an invoke activity that sends a response back to the client BPEL process, using the WSDL partner link.