This object specifies the type of start time of the SOAM DM session. The start time can be disabled (none), immediate, relative, or fixed. The value of 'none' is illegal and a write error will be returned if this value is used. The value of 'immediate' starts the SOAM DM session when the osSoamDmCfgEnabled is true. This value is used to select a proactive PM session. The value of 'fixed' starts the SOAM DM session when the osSoamDmFixedStartDateAndTime is less than or equal to the current system date and time and osSoamDmCfgEnabled is true. This value is used to implement an on-demand fixed time PM session. The value of 'relative' starts the SOAM DM session when the current system date and time minus the osSoamDmRelativeStartTime is greater than or equal to the system date and time when the osSoamDmCfgStartTimeType object was written and osSoamDmCfgEnabled is true. This value is used to implement an on-demand relative time PM session. This object can only be written at row creation time and cannot be modified once it has been created.