Method for excluding a participant from a group having authorized communication

A method for excluding a participant from a group of multiple participants, in which certificates are used for an authorized communication of the participants among each other, a withdrawal request being received by one participant of the group, the withdrawal request making an identification of the participant to be excluded possible by the participant to be excluded itself, and the authorized communication being terminated by the participant when it is identifiable as the participant to be excluded based on the withdrawal request, as well as a communication system for carrying it out.