In a method for operating a communication system having a plurality of nodes which have access to a shared channel, a transmission process for transmitting a message via the channel is monitored for bit errors, and when a bit error occurs, a signaling message is transmitted via the channel in order to signal the bit error. In order to allow communications processes between the nodes to be controlled as a function of a bit error rate of the channel, a signaling rate of the signaling messages is measured and a bit error rate of the channel is determined as a function of the signaling rate.