The conversion of the calling number information from an implicit format into an explicit one is also carried out in two steps:

Step 1:

With the aid of the KNPRE settings, any breakout codes or prefixes contained in the implicit number are removed.

Step 2:

The modified/shortened number is then set to the highest format (TON=INTERNAT) on the basis of the ISDN code settings in the TDCSU AMO. If a destination node in the network, or the ISDN exchange, requires a lower format, this can be set with the aid of the KNFOR AMO, in cases where this is possible.