This operational attribute is maintained by the server and appears to be present in every dynamic entry. The attribute is not present when the entry does not contain the dynamicObject object class. The value of this attribute is the time, in seconds, that the entry will continue to exist before disappearing from the directory. In the absence of intervening "refresh" operations, the values returned by reading the attribute in two successive searches are guaranteed to be nonincreasing. The smallest permissible value is 0, indicating that the entry may disappear without warning. The attribute is marked NO-USER-MODIFICATION because it may only be changed by using the refresh operation.