This read-only enumerated value reports which ATM traffic-contract service category - Constant Bit Rate, Variable Bit Rate, or ABR - a given channel is provisioned under. Admins check this when evaluating whether a channel's bandwidth guarantees and cell-rate parameters match its intended traffic type, since CBR channels expect steady-rate traffic while VBR/ABR channels expect bursty or rate-adaptive traffic. For example, a voice circuit provisioned as cbr would be expected to have a fixed peak cell rate with little tolerance for burstiness, unlike a vbr data channel.