ACM Instance State Handling at Element Upgrade

At upgrade of an element in an ACM instance, say for example we want to upgrade a participant and all the instances in the participant without taking down the compositions, how do we achieve that?

• Store data independently of ACM element in CPS or some such system

• Allow restart of an ACM element and reload from CPS

• Reload the ACM properties (lightweight solution)

CPS could be used to store composition data. The life cycle of the data is tied to automation composition instances. That means that when you onboard a composition, it could come with a yang schema specific to that composition and we could life-cycle the schema as part of the commissioning process. When the Automation Composition instance is created, the elements will be instantiated and a CPS anchor could be created for the composition instance. That would also mean that when the composition  Instance is removed, the CPS anchor we created (and its associated data) would be removed.

It would  be interesting to do one or both of the following;

1. Be able to share the same data (common data) across multiple compositions and multiple composition instances

2. Be able to upgrade a composition instance (e.g. a software fix) and still use the same data.

Would this mean:

1. Be able to share the same automation composition element between two automation composition instances?

2. Be able to modify the definition of an existing automation composition and instance to use new artifacts?