# SS5 and NCC service call control

When applications perform NCC service call control with the SS5 protocol, they can process digits in the following ways:

Method of processing digits | Description
Inbound calls: Receiving digits all at once | With SS5 TCPs, after NCCEVN_INCOMING_CALL is received, the calledaddr field in the NCC_CALL_STATUS structure contains all received digits. The callingaddr, usercategory and tollcategory fields are NULL. The parameter NCC.X.ADI_SS5.digitnumber determines the number of digits the TCP should expect from the calling party. The default is 7.
Inbound calls: Receiving digits one at a time | The SS5 TCP does not recognize ANI or category digits. Digits are presented in the order in which they arrive. The NCC.X.ADI_SS5.digitnumber parameter determines how many digits to expect, but is active only if the outbound party does not send an ST tone (end of dial) at the end of register signaling.
Outbound calls: Formatting digits | Two KP digits are possible in the SS5 protocol. These are KP1 (D, the starting digit for national calls), and KP2 (E, the starting digit for international calls). KP1 is the default KP tone, so if the application wants to use KP1 as the starting digit, the callingaddr argument used with nccPlaceCall is formatted as follows: d 1...d n If the application wants to send a different KP digit, the callingaddr argument used with nccPlaceCall is formatted as follows: # KP# d 1...d n (where # is a conventional NMS separator)

Caller ID is not supported in SS5 TCPs.