Executing multiple tasks parallely in a process is implemented using split joins in OSB.

E.g. Need to implement a process which will interact with 2 different functionality which will return job details and personal details of an employee separately. So both the functionalities does not depend on each other. In such a case in can invoke the both the functionalities at a time in parallel.

Implementation: Refer the below URL for implementation.

https://drive.google.com/file/d/0Bz9wGhXL_T6WU2Z3TWpuOXlXcXM/edit?usp=sharing