This read-write integer is the control object an admin uses to reboot the Clarent element gracefully, by first setting it to enableShutdown(0), which triggers the Clarent shutdown trap, and then to startShutdown(2) to actually begin the shutdown, with disableShutdown(1) as the default that blocks shutdown until re-armed. It exists to enforce a deliberate two-step confirmation before a network element carrying live calls is taken down. For example, an admin planning maintenance sets cSysOperation to enableShutdown(0) first, waits for the shutdown trap notification, then sets it to startShutdown(2) to actually reboot the element.