How do I implement pause and resume in BPM process

[sarveshmvm]

Hello all,

Is there a way to call the BPM process from a rest API by signalling asynchronously. 

In other words, I have a requirement where I have to pause the process flow and wait for a trigger from the external rest service and that service should trigger the signal to resume the process. Any ideas will be helpful . This has to happen asynchronously as well will have too may process running parallelly.

Kindly suggest me a solution.