# Natural Access media masks and call progress masks

Natural Access uses a media mask and a call progress mask that affect DSP resource management. These NCC Service masks are:

- NCC.X.ADI_START.mediamask

- NCC.X.ADI_PLACECALL.CALLPROG.precmask

These masks indicate DPFs that will execute on the board. If any of the bits in either of these two masks are set, the DPFs relating to the set bits must be specified in the Resource[x].Definitions keyword. Since the bits in the media mask are set by default, the DPFs that correspond to these set bits are in the default Resource[x].Definitions keyword in the templates. For more information about these masks, refer to the Natural Access Developer's Reference Manual.