Abstract: The invention relates to a method for processing a payment operation via a credit card financial service provider in electronic commerce in an open network, particularly on the Internet, between a purchaser and a trader, where the credit card financial service provider transmits a transaction code which is valid for one payment operation to the purchaser at the latter's request, and the purchaser uses this transaction code instead of his credit card number when processing the payment operation with the traders.

Abstract: A method for interchanging and routing messages in a telecommunications system having at least one computer network and at least one switching-oriented network with at least one telecommunications terminal with a telephone number, which are connected to one another via a number of gateways which are set up for transmitting voice messages, with a gateway that is most cost-effective for voice transmission being associated with a name which is formed from parts of the telephone number which can be predetermined.