nrt-VBR
non real-time variable bit rate
nrt-VBR is an ATM service category that guarantees low cell loss and low delay for applications, such as video and frame relay, which are characterized by an on/off source with known, predictable transmission patterns. During the on period, cells are transmitted at the peak information rate. No cells are transmitted during the off period. nrt-VBR allows statistical multiplexing gains using the traffic descriptors (PCR and SCR). It does not provide delay commitments.