This object sets the ATM traffic class for virtual channels assigned this profile: constant bit rate, real-time or non-real-time variable bit rate, unspecified bit rate, or available bit rate. Admins choose the class that matches the traffic's tolerance for delay and rate variation, such as CBR for voice or UBR for best-effort data. For example, setting this to cbr(1) configures channels using this profile for constant bit rate traffic like voice circuits.