ATM switching node design based on a versatile traffic descriptor

Because of the high speed, the provision of unrestricted bandwidth on demand by ATM-based B-ISDN can only be satisfied by sacrificing network resource utilization. In ATM networks, the network resources are link bandwidth and node buffer space. A new traffic descriptor which directly specifies the resource requirements of ATM traffic streams in terms of bandwidth, buffer space and a set of parameter adjustment rules is proposed. We call this a versatile traffic descriptor (VTD) because it can describe relevant characteristics of all ATM traffic streams including nonstationary traffic streams. Also, the VTD incorporates both the traffic description and the user´s QoS specifications. Therefore, there is no need to specify the QoS requirements separately. A radically new, VTD-based switching node design, which uses novel per-connection buffering scheme and service scheduling scheme is also proposed. It is conjectured that the proposed earliest due date (EDD) service scheduling scheme is optimal in per-connection burstiness reduction