# Stopping an ISDN protocol stack instance

To stop an ISDN or DPNSS protocol stack instance, use one of the following methods:

- Stop the ISDN daemon (isdncta), if it is running.

- Call isdnStopProtocol from within the application that called isdnStartProtocol.

Either method shuts down the ISDN protocol stack instance, and releases all on-board resources and buffers formerly used by the stack instance.

The ISDNEVN_STOP_PROTOCOL event contains the completion status of the stop request. If the stack instance stopped successfully, the value field in this event contains SUCCESS. Otherwise, another reason code appears here.

For more information about isdnStopProtocol, see the Dialogic® NaturalAccess™ ISDN Messaging API Developer's Manual.