6.4.5 Carrier network operators

If a fixed network subscriber of Telekom Austria wishes to make, and pay for, his calls via one of the new network operators, although the new network operator did not connect this subscriber line to his network, the customer only needs to dial the combination of digits "10xx" before dialling the desired number at destination (always with the local network area code, just as when making calls from a mobile phone). The two-digit code "xx" always clearly identifies the desired operator. What is needed beforehand is an agreement with the respective operator, who acts as "carrier network operator" in this case (in the variant operator selection / carrier selection or "Call by "Call"). Telekom Austria forwards the call from the selected carrier network operator ("origination") and sets up the connection to the requested destination ("termination" in the target network). During the first semester 2000, "Carrier Pre-Selection" was introduced in Austria as an additional pre-selection process. This is an alternative to dialling "10xx" for every call, enhancing the convenience of end users. Previously, this had only been possible by using so-called "routers" (an additional piece of equipment that is interconnected between the telephone and the network termination socket and that automatically adds the "10xx" before the sequence of numbers dialled by the subscribers).

In the case of Carrier Pre-Selection, a note is entered into the relevant subscriber connection data of a Telekom Austria subscriber at the relevant subscriber switching exchange that all connections are to be routed to the "pre-set" carrier network operator. It is always very easy to override a pre-selection when making a new call (by dialling 1001). After removing carrier pre-selection it is possible to make the next call as though there were no active carrier pre-selection for this line.

For various reasons, carrier selection and carrier pre-selection is not effective for all target numbers. The entire series 1 (call numbers in the public interest, e.g. emergency call numbers) and all services numbers are exempt. In the latter case, the target network operator fixes a uniform end-user rate for all networks (together with the services provider). These are so-called "target-network-tariffed" services numbers.

Until year-end 2000 the Telekom Austria network, in its switching exchanges, did not allow for a differentiated treatment of calls in specific groups of numbers, depending on whether carrier selection or carrier pre-selection had been chosen for a call. The TKK ruled a different handling, for example, for the segments of numbers that were not covered by carrier (pre-)selection. Whereas, in the case of carrier pre-selection (which does not include these numbers), such calls are to be transmitted by Telekom Austria via its network, in the case of carrier selection, where a subscriber explicitly indicates for every connection that a specific call be handled via the indicated carrier network operator (and that the subscriber be invoiced only by that operator), the connection is not made, or the subscriber is informed accordingly by an announcement that the connection cannot be made. Moreover, a configurated carrier pre-selection for local calls (i.e. calls within the same local network) was only effective if the respective local network area code was also dialled. Since 01 January 2001, these technical constraints no longer apply. However, it is still not possible to handle certain specific number segments individually for (carrier) network operators, i.e. there are individual call number segments where traffic is only forwarded to all or to none of the carrier network operators.