A new RAN App module in RAN-Sim is an abstraction of the function provided by an xApp to support A1-based actions. For Kohn release, RAN App will provide the following functions to support A1-based action for the ANR SON use case:

1. Receive A1 policy message over Kafka bus from A1 Termination
2. Communicate via websocket with RAN-Sim Controller to control the CU/DU NF in the Honeycomb NF modules, to achieve an end result similar to what an xApp would have done over E2.

For Kohn release, the A1 message received has handover (HO) related kpis and RAN App will effect a change in the configuration of the NR Cell Relation property in the appropriate CU(s).