移动实时数据库系统中的更新分发  

Updates Dissemination in Mobile Real-Time Database Systems

作　　者：李国徽[1] 王洪亚[1] 刘云生[1] 

机构地区：[1]华中科技大学计算机科学与技术学院,武汉430074

出　　处：《计算机研究与发展》2005年第11期2004-2009,共6页Journal of Computer Research and Development

基　　金：国家青年自然科学基金项目(60203017);教育部优秀留学回国人员基金项目;湖北省自然科学基金项目~~

摘　　要：数据广播作为移动计算环境下有效的数据分发技术已有许多研究,当数据广播用于发送不断更新的数据时称它为更新分发·现有的更新分发协议因没有考虑实时数据库系统中数据和事务的定时要求而不适合移动实时只读事务的处理·重点研究了移动实时数据库系统中更新分发的问题,提出了混合前向多版本数据广播协议,该协议在保证事务一致性的同时满足了数据和事务的定时约束·模拟实验表明,该协议能够有效地降低事务错过率和提高数据流行性,较现有更新分发协议更适合移动实时只读事务的处理·Data broadcast is a widely accepted data dissemination method for mobile computing systems and has held a lot of interest of relevant researchers. When data broadcast is used to disseminate frequentlyupdated data it is called updates dissemination. Existing updates dissemination protocols are unsuitable for mobile real-time read-only transaction processing because they don＇ t consider the real-time constraints on both data and transactions in mobile real-time database systems. In this paper a new updates dissemination protocol called hybrid forward multi-version data broadcast （HFMVB） is proposed. HFMVB not only guarantees the consistency of read-only transactions, it also provides higher data currency and lower miss rate by shortening the consistency interval, instantly broadcasting updates and utilizing broadcast ondemand. Simulation results show that HFMVB has better performance compared with the existing updates dissemination protocols and is more appropriate for mobile real-time database systems.

关 键 词：移动实时数据库系统 移动实时只读事务 更新分发 混合前向多版本数据广播 

分 类 号：TP311.13[自动化与计算机技术—计算机软件与理论]