Wei Zhengxian, Song Min, Yin Guisheng, Song Houbing, Wang Hongbin, Ma Xuefei, Cheng Albert M K
College of Computer Science and Technology, Harbin Engineering University, Harbin 150001, China.
System Engineering Innovation Center, Systems Engineering Research Institute, Beijing 100094, China.
Sensors (Basel). 2017 Oct 17;17(10):2374. doi: 10.3390/s17102374.
Underwater wireless sensor networks (UWSNs) represent an area of increasing research interest, as data storage, discovery, and query of UWSNs are always challenging issues. In this paper, a data access based on a guide map (DAGM) method is proposed for UWSNs. In DAGM, the metadata describes the abstracts of data content and the storage location. The center ring is composed of nodes according to the shortest average data query path in the network in order to store the metadata, and the data guide map organizes, diffuses and synchronizes the metadata in the center ring, providing the most time-saving and energy-efficient data query service for the user. For this method, firstly the data is stored in the UWSN. The storage node is determined, the data is transmitted from the sensor node (data generation source) to the storage node, and the metadata is generated for it. Then, the metadata is sent to the center ring node that is the nearest to the storage node and the data guide map organizes the metadata, diffusing and synchronizing it to the other center ring nodes. Finally, when there is query data in any user node, the data guide map will select a center ring node nearest to the user to process the query sentence, and based on the shortest transmission delay and lowest energy consumption, data transmission routing is generated according to the storage location abstract in the metadata. Hence, specific application data transmission from the storage node to the user is completed. The simulation results demonstrate that DAGM has advantages with respect to data access time and network energy consumption.
水下无线传感器网络（UWSNs）是一个研究兴趣日益增加的领域，因为UWSNs的数据存储、发现和查询一直是具有挑战性的问题。本文针对UWSNs提出了一种基于引导图（DAGM）的数据访问方法。在DAGM中，元数据描述数据内容的摘要和存储位置。中心环由根据网络中最短平均数据查询路径的节点组成，用于存储元数据，数据引导图在中心环中组织、扩散和同步元数据，为用户提供最省时、节能的数据查询服务。对于该方法，首先将数据存储在UWSN中。确定存储节点，将数据从传感器节点（数据生成源）传输到存储节点，并为其生成元数据。然后，将元数据发送到离存储节点最近的中心环节点，数据引导图组织元数据，将其扩散并同步到其他中心环节点。最后，当任何用户节点中有查询数据时，数据引导图将选择离用户最近的中心环节点来处理查询语句，并基于最短传输延迟和最低能耗，根据元数据中的存储位置摘要生成数据传输路由。从而完成从存储节点到用户的特定应用数据传输。仿真结果表明，DAGM在数据访问时间和网络能耗方面具有优势。
