Design pattern or Framework for a 2-systems interface

I have 2 systems A and B and I want to achieve a 2 ways asynchronous communication between them. System B is out of my scope and has a proprietary communication protocol. A part from sending and receiving "business" events between systems, the status of the connection must also be monitored, configured and restart if necessary.

I wonder what are the design patterns available. I've started with an observer/observable pattern. But I feel that monitoring and restarting the connection is something different. I also wonder if would be better to consider also some queuing/messaging framework.

Performance or traffc volume and scalability is not an issue.