有效减小时延的自适应p-坚持CSMA协议研究  

Research of adaptive p-persistent CSMA protocol for reducing delay

作　　者：黄旭方[1,2] 王旭阳[1] 孙鑫[1] 陈冰雪[1] HUANG Xufang;WANG Xuyang;SUN Xin;CHEN Bingxue(School of Computer, Electronics and Information, Guangxi University, Nanning 530004, China;Guangxi Colleges and Universities Key Laboratory of Satellite Navigation and Position Sensing, Guilin, Guangxi 541004, China)

机构地区：[1]广西大学计算机与电子信息学院,南宁530004 [2]广西高校卫星导航与位置感知重点实验室,广西桂林541004

出　　处：《计算机工程与应用》2017年第12期99-104,共6页Computer Engineering and Applications

基　　金：国家自然科学基金(No.61563004);南宁市科技攻关项目(No.20141033)

摘　　要：针对一些对实时性要求较高而数据吞吐量不高的网络服务,提出一种有效减小时延的自适应p-坚持CSMA/CD协议算法。依据与网络性能相关的关键参数之间的关系,提炼出能有效反映网络负载的状态监测量,基于对监测量的联合判断结果,将网络分为轻负载、较轻负载、较重负载和重负载四种状态,并针对不同负载状态调整发送概率p和最大避退上限值B_m。通过对协议的时延、吞吐量和总线利用率进行仿真,与一般的p-坚持CSMA/CD协议相比,自适应p-坚持CSMA/CD协议能较有效降低时延、减小抖动。According to some real time sensitive network require for common data throughput,an adaptive p persistentCSMA/CD protocol for reducing the delay effectively is proposed.Firstly,the monitoring variables reflecting the networkstatus will be found out,based on the monitoring values,the network status is classified into four types,the light load status,the relative light load status,the relative heavy load status and the heavy load status.Then the sending possibility pand the maximum back-off threshold Bm will be adjusted dynamically based on the judged network status.Finally,thedelay and throughput and bus utilization of networks are simulated.The result shows that the adaptive p persistent CSMA/CDprotocol can effectively reduce delay and jitter.

关 键 词：时延 避退上限 CSMA/CD协议 自适应 

分 类 号：TP393[自动化与计算机技术—计算机应用技术] TN915[自动化与计算机技术—计算机科学与技术]