Both methods of number modification - LCR and INS - are basically different, but cannot be observed separately from each other. LCR thus ultimately decides on the route of a call and thus on the numbering plan to be used (AMO LODR with the NPI command). Since the numbering plan demanded by the destination number for a certain route also corresponds to that of the information numbers by default (e.g. in case of a CO exit, all numbers must be from the NPI=ISDN numbering plan), the numbering plan of the destination numbers from LCR is also used for the information numbers. The other information such as TON and screening indicator is either derived from the node format table (set with AMO KNFOR) or set by default and thus determined independent of LCR.

RULE:

If numbering plans not equal to NPI=UNKNOWN are used in a node, each route element (AMO LDAT) is to be assigned the respective numbering plan (NPI) and the type belonging to the destination number (TON) in the corresponding outdial rule (AMO LODR).

In AMO RICHT, a virtual destination node number and a physical destination node number must be defined. The virtual destination node number is used for number modification and, for example, also displayed in charge tickets. The physical destination node number is mainly used for the closed numbering of the assignment of subscribers with destination numbers to destination node number.

If a node has a partner node that hides several virtual nodes, a route must be defined for every virtual node. In the dial plan (AMO LDPLN), entries must be made in such a way that the right virtual destination node can be addressed. In extreme cases, complete numbers including the extension must be configured to guarantee the assignment of subscribers to various virtual nodes (NNO).

Example: In PABX 1, Subscriber 4711 is administered in VKN 1 and thus available with tie line code 777. Subscriber 4712 is also in VKN 1, but administered in PABX 2. This situation may have arisen due to a move of Subscriber 2 from PABX 1 to PABX 2 while keeping the numbers. VKN 1 thus extends to two physical nodes. In the partner node PABX 3, the dial plan entry must take place as follows: The digit pattern "777 4711" is assigned to Route 1 with DNNO = VKN1, while the digit pattern "777 4712" is assigned to Route 2 with DNNO = VKN2.

The virtual destination node number entered in AMO RICHT always describes the remote destination, i.e. the end point of a call. Since no differentiation dependent on the distance is possible here, however, a destination node number that is valid for a certain route is entered in AMO LDAT. The LDAT and not the RICHT destination node number is thus used for the modification. This could be the case, for example, if rerouting takes place via the central office for an originally network-internal call. In the rerouting node, the central office or a fictive node number that deviates from AMO RICHT can be entered as the destination node - dependent on route - thus resulting in an accordingly different reaction.

If a number is to be transferred from one numbering plan to another, this is a case of "Transit Interworking." This transfer takes place by placing the codes of the new numbering plan before the original number (implicit format). An explicit number of 89-722-99-4711 with NPI=ISDN and TON=NATIONAL, for example, thus arises from number 99-4711 with NPI=UNKNOWN and TON=UNKNOWN (OpenScape 4000 specific numbering plan) for a transfer to the ISDN CO numbering plan. Since various problems can arise with this method (e.g. a central office does not accept the number since 99-4711 does not come from the assigned group of numbers), the signaling of the information numbers can be entirely prevented in such a linkage case by setting LATTR=SUPPCPN (no display of A subscribers) in LDAT for certain routes. Instead, a permanent, substitute number set by AMO KNMAT (e.g. attendant console number) can be sent instead.