A Preemptive Local Fairness Ring Protocol for Multimedia Transmission Services

• Main Authors: Tang, Yao-Yao, 唐瑤瑤
• Other Authors: Chung Tein-Yaw
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/15662236974422965069

碩士 === 元智工學院 === 電機與資訊工程研究所 === 84 === In this paper we propose an enhanced protocol called Preemptive Local Fairness Ring ( PLFR ) whih is a slotted counter-rotating dual-ring MAC protocol. In PLFR, a local fairness algorithm is used to maintain the fairness control of high priority data between nodes on the ring. Local fairness that is initiated only when starvation occurs can optimize the benefits of destination stripping. In addition, local fairness should only involve segments of interfering, as opposed to global, nodes. Thus, several nodes may transmit data at the same time. This significantly improves network bandwidth utilization. To preempt low priority data on the ring, PLFR uses an insertion buffer in the ring interface of each node. A node can transmit its high priority data by withholding a pass-by low priority data on the ring. This significantly reduces the access latency and cell delay variation of time delay data. Furthermore, low priority data is guaranteed to be delivered in sequence. We define three different scenarios to compare the performance between PLFR, Orwell and MetaRing. The simulation results show that PLFR can provide the best quality of service for time delay sensitive data.