Providing quality of service over advanced switching

Advanced switching (AS) is a new fabric-interconnect technology, which provides the advanced features of existing proprietary fabrics in an open standard. AS is intended to proliferate in multiprocessor, storage, networking, servers, and embedded platform environments. The provision of quality of service (QoS) in computing and communication environments is currently the focus of much discussion and research in industry and academia. AS provides some mechanisms, which correctly used permit us to provide QoS. In this paper, we examine these mechanisms and show how to provide QoS based on bandwidth and latency requirements. Furthermore, we propose a new algorithm based on the self-clocked weighted fair queuing (SCFQ) algorithm, which we call SCFQ credit aware (SCFQ-CA), as an implementation of the AS minimum bandwidth egress link scheduler. Finally, we show that the AS table-based scheduler does not work properly with variable packet sizes, and we propose a modification of the table scheduler, based on the deficit table (DTable) scheduler, to solve this drawback