A communication terminal into which communication data can be input and which can receive a message signalling that at least one further communication terminal is ready to receive the communication data. Following receipt of the message, a transmission device configured to operate in a first mode, in which it sends data at a first data rate, and in a second mode, in which it sends data at a second data rate, which is higher than the first data rate, is used to send the communication data in the second mode.