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With the rapid development of network technology, communication technology, positioning technology, the the request service model of network navigation services (Network Navigation Services, NNS) have undergone tremendous and profound changes. The user server clusters rely on network data from different departments can be integrated parsing that best meet the navigation needs of the user, the application of raster and vector geospatial data classification chunked transfer; With the rapid development of network technology, Web network, wireless network, SMS / MMS and other ways to send a request to the server-side, or through the Web network, the WAP network, MMS, etc. network navigation services. To sum up, studied in this paper include: 1. Increasingly diversified network navigation service request mode, users can network through the Web, wireless network, or send an SMS / MMS own query passes the request to the server. But the query is still relatively simple keyword-based, multi-attribute queries. Parsing can not provide picture information, spatial data analysis, query, and thus support the weak, the user's fuzzy queries and user query experience is not friendly enough. The paper discusses the network navigation services in data transmission principle, navigation service mode. The entire process of data transfer between client and server cluster expressions. Agent, Ajax and other hot technologies for paper applications are reviewed to explain. High network navigation services for geospatial data requirements. Expression of geospatial data in two formats, the respective advantages and disadvantages of vector data and raster data are discussed, as two complementary data format, the paper proposed the integration of vector and raster data network navigation services thinking. Constructed formalization method of NNSOntology body, the agent body, the structure of the Agent-based the SVG data transmission system; raster map-based Web network users query system, the MMS mobile terminal receives the simulation. Paper innovation is mainly manifested in the following aspects: 1. Heterogeneity of expression is limited, the server database for SMS / MMS request mode, mapping XML rules-based command parsing, shielding the differences of heterogeneous platforms and database method. For raster map data accuracy is not high, the client has a complex processing capabilities can not display their navigation data can not be updated from time to time to the user on-demand transmission; expression of vector data exist of heterogeneous sexual transmission bottleneck problem, thesis the thought of raster data and vector data integration. With complex topology relationship The rich map information expressed by the raster map its as basemap transmission to users, dynamic navigation and real-time updates of data transferred to the user in the form of vector data. Vector data the heterogeneity transmission bottleneck problem discussed in the paper such a common international standard SVG data format as vector data carrier network transmission, shielding data heterogeneity differences. Network environment is not optimal, network transmission delay, propose to utilize the advantages of Multi-Agent Systems in a distributed environment, Ajax ATM to improve data transmission stability, to give a more user-friendly and interactive experience smooth .
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