ADPQ: an adaptive approach for expedited forwarding traffic scheduling

The goal of expedited forwarding (EF) behavior is to provide a definition for low-loss, low-delay, and low-jitter service for network nodes that implement differentiated services (DiffServ) framework. Having strict timing requirement, EF traffic needs accurate and simple scheduler. Available simple schedulers suffer from various problems like starving low quality traffics and producing long bursts in the core of network. On the other hand, accurate approaches are expensive to implement in higher rates. Adaptive priority queue (ADPQ) is an adaptive approach which can control a node's output burst and removes the starvation threat while preserving delay- and jitter-constraints of delay-sensitive EF traffic. It is cheaper than fair queuing (FQ) techniques and presents great performance in face of TCP flows.