Explicit delay/jitter bounds for real-time traffic over wireless ATM

A high performance, frame-based, real-time ATM scheduler is proposed for the wireless multimedia environment. We introduce the Delayed Frame Queueing (DFQ) scheduling protocol which only defines the service priorities, deadlines and eligibility times of queued cells. The DFQ protocol does not define the particular fashion in which a mobile or base station gains access to the shared transmission medium; thus, we present DFQ as a generic protocol which can be combined with numerous types of MAC protocols. Key features of our strategy are its algorithmic and architectural simplicity, its non-ad hoc scheduling approach, and its unified treatment of all real-time streams at all service queues within a wireless ATM network. In addition, the delay and jitter bounds are uncoupled. In this way, end-to-end jitter can be tightly controlled even if medium access requires long indeterminate waiting durations.