Communications unit for selecting the least-cost route

Described is a communication agent unit (KAE) with access to a charge calculation module (CHARGE) and a time module (TD). The communication agent unit (KAE) has a processor controller (CPU) which observes the communication behavior of a subscriber and detects regularities by comparing communication parameters of that subscriber. The processor controller (CPU) selects the most favorable service provider among a plurality of service providers for a current communication event depending on charge-related communication parameters, assuming that the regular communication behavior is maintained even in the current communication event.