Research On Fair Scheduling Algorithm Based On Buffered Crossbar

On the continuous progress of network technology and expanding of network applications, the amalgamation has been becoming the trends that the network develops. Internet has changed from single network that carries data into the "all traffic" and uniform carrying platform that integrates data, voice, image and real time multi-media information. The routing and switching equipment is the core of network node and it must meet the explosion of information capacity and the diversification of applications to establish a basic platform which has extensibility, multicast and QoS(Quality of Service) for uniform carrying network and applications managing after "the amalgamation of three networks". Combined with the requirements of projects, aiming at the deficiency of switching technology on fairness service and multicast, basing on buffered crossbar, the dissertation focuses on the topics of extensibility, fairness service and multicast. based on the research fruits, it comes up with an engineering design which is practical and can meet the integration traffic of unicast and multicast.Its main work and fruits are outlined as follows:The issue that schedules fairly based on flows in CICQ(Combined Input and Crosspoint Queuing) is analyzed. Based on the analysis, a Fair Service and Group Smoothed Round Robin(FGSR) algorithm which can provide delay and fairness guarantee for arriving flows is proposed. FGSR adopts stratified and classification method whose complexity is O(1). Its each input/output can individually support variable length packet switching. The theoretical analysis and simulation results show that FGSR can provide delay-bound, throughput and fair service guarantees for various arriving traffic flows without speedup.Based on CICQ switches, the fair scheduling problem of integration unicast and multicast is discussed, a fair and simple high performance scheduling algorithm for integration traffic of unicast and multicast based on buffered crossbar is proposed, which is called Multicast and Unicast Hybrid Fairness Scheduling(MUHF). MUHF introduces double round robin and piggyback scheduling mechanism, in which each input/output can individually support variable length packet switching and maintains O(1) complexity. Simulation results show that MUHF exhibits good delay, throughput and fairness performance.Aiming at the research and development requirements of "Fundamental Research on the Architecture of Universal Trustworthy Network and Pervasive, New Generation Highly Creditable Network", combined with the fruits of fairness and unicast/multicast hybrid scheduling, and based on buffered crossbar and load balanced Birkhoff-Von Neumann switch, this dissertation constructs a load balanced multicast and unicast fair scheduling switching system which can provide fairness for hybrid traffic. LB-MUF has O(1) complexity and is very easy to implement. LB-MUF can deal with variable length packets and avoid time overhead of segmenting and recombining. Simulation results show that LB-MUF exhibits good delay and Jitter performance.The dissertation researches on high performance switching mechanism of fairness service and scheduling integration of unicast and multicast based on buffered crossbar. The simulation results validate the algorithms. The fruits advance fairness service and unicast/multicast supporting of switching system. But owing to limited time and researching level, some problems still need to be studied. Relying on the work of the dissertation, we can study more on supporting differentiating service and multicast switching technology which applies network coding.