# MFS and NCC API call control

When applications receive calls using NCC API call control with the MFS protocol, they can receive digits in the following ways:

- All at once

- One at a time

## Receiving digits all at once

For MFS, after NCCEVN_INCOMING_CALL is received, the following fields in the NCC_CALL_STATUS structure contain the received digits:

Field | Description
calledaddr | Called number. Also referred to as the direct inward dial (DID) number.
callingaddr | Calling number (if available). Also referred to as the automatic number identification (ANI) number.

The following field is in the NCC_CAS_EXT_CALL_STATUS structure:

Field | Description
usercategory | Call category.

Several entries in the TCP parameter file affect the way the MFS TCP accepts and processes digits.

MFS parameter | Description
NCC.X.ADI_MFS.DIDnumber | Number of direct inward dial (DID) digits the TCP should expect from the calling party. Default is 5.
NCC.X.ADI_MFS.ANInumber | Number of automatic number identification (ANI) digits the TCP should expect. Default for the Spanish National Numbering Plan is 9. This value should not be changed, unless it is set to zero; in this case no ANI digits are collected.
NCC.X.ADI_MFS.anifirst | Indicates if the inbound part of the MFS TCP requests the ANI digits or the DID digits first. Signaling-wise, there is no difference between the two options, both being equally supported by the specifications.

Refer to Configuring TCPs for information about loading parameter files.

## Receiving digits one at a time

For MFS, the digits appear in the following format:

d 1...d 5 # a 1...a 9 if receiving DID digits first.

a 1...a 9 # d 1...d 5 if receiving ANI digits first.

d 1...d 5 if not receiving ANI digits.

where:

Value | Description
d 1...d 5 | DID digits received (always 5 in Spain for a CPE).
a 1...a 9 | ANI digits received.
# | Separator symbol.