田间数据传输同步策略与中间件研究

Research on Field Data Transmission Synchronization Strategy and Middleware

移动终端的田间信息采集相比于传统的田间信息采集,具有灵活性强、采集方便等优势,已成为田间信息采集的主要手段之一。但是在进行田间信息采集时存在数据同步问题,主要表现在慢同步频发、无为数据(已经传输过的数据)重传、服务器端变化数据没有及时同步到移动终端等问题。针对这3个数据同步的主要问题,基于Sync ML协议,提出了慢同步策略,并对该协议进行了改进;设计了主动推送策略和变化数据捕获策略;在此基础上设计并且实现了改进后的移动数据同步中间件,并且把该中间件应用到种业科研育种田间信息采集系统和水稻定位试验打分系统中,试验证明,该中间件提高了数据同步的效率,减少了无为数据的重复传输,表现出良好的实用性和普适性。

Compared with the traditional field information collection,field information collection with mobile terminal has strong flexibility,easy collection and other advantages,and has become one of the main means of agricultural field data acquisition. But when the field information was collected,data synchronization has disadvantages of slow sync frequency,unnecessary retransmission of data,and serverside changes, which can not synchronize to the mobile terminal timely. The grammar and data synchronization process of the Sync ML protocol was lucubrated,the data synchronization process of mobile data acquisition was analyzed and various problems were encountered. Sync ML protocol was improved,slow synchronization strategy was proposed,and active push synchronization strategy and change data capture strategy were designed. The strategy of combining pull synchronous with push synchronous was designed,the push synchronous was used to push synchronous messages,and the pull synchronous was used to synchronize the data from server. The data synchronization strategy middleware was designed and implemented. Mobile terminal based on Android and C # technology was used. The middleware was used in information acquisition system and rice-positioning-test-score system. The results showed it significantly improved the efficiency of data synchronization and reduced the unnecessary retransmission of data. It makes the field information collection system in favor of the promotion of modern information agriculture,and enhances the work efficiency of field data acquisition and data accuracy. The experimental results verify that the middleware has high practicability and universality,and makes data transmission not increase as the number of the synchronization.