This object contains an appropriate value to be used for xcIndex when creating entries in the xcTable. The value 0 indicates that no unassigned entries are available. To obtain the xcIndex value for a new entry, the manager issues a management protocol retrieval operation to obtain the current value of this object. After each retrieval, the agent should modify the value to the next unassigned index. After a manager retrieves a value the agent will determine through its local policy when this index value will be made available for reuse.