Abstract: A device for transmitting communications data between a computer and further computers of a computer network, in particular the Internet, via a communications (i.e. telephone) network. The device has a memory for storing address data which contains at least two different Internet addresses or telephone numbers of the communications network at which a user can access the computer network. A selection unit selects the most economical Internet access, or the respective telephone number of the Internet provider, as a function of the cost data provided for each of the stored Internet addresses.