Description: The xdslDevIfConfigTable provides config information specific to a xDSL device, or system. The table is indexed by an object which corresponds to ifIndex. These ifIndex entries, themselves, denote and identify specific xdsl interfaces on the board or module. Also the configuration parameters are grouped into two broad categories, 'up' and 'down'. 'up' reflects the upstream direction (from the customer premises to the central office). 'Down' reflects the downstream direction (from the central office to the customer premises)