The value of the object tmnxLocUsrDbPppoeMaskSufNum specifies
the number of characters to remove from the end of the incoming
string before it is matched against the value configured in the
corresponding object in the tmnxLocUsrDbPppoeTable.
At least one of the values of tmnxLocUsrDbPppoeMaskSufNum and
tmnxLocUsrDbPppoeMaskSufStr must be equal to the default value.