OPC UA provides a client-server communication model that includes status information. This status information is associated with a session. A session is defined as a logical connection between a client and a server. Each session is independent from the underlying communication protocol; any issues occurring at protocol level do not automatically cause the termination of a session. The sessions terminate following an express request from the client or due to the client's inactivity. The inactivity intervals are set during the creation of a session.