This attribute specifies the default control mode of Performance
Monitoring (PM) measurements for all AtmIf Vcc and AtmIf Vpc
connections on the ATM interface.
autoStart means Performance Monitoring (PM) measurements start
when the provisioned data is activated.
onDemand means PM measurements start when the operator issues
the START conmmand. The PM measurements in this mode will
continue until the operator issues the STOP command.