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In order to upgrade the WebGIS legacy systems smoothly, and improve the response speed of traditional WebGIS and user experience, this paper designs and develops a tile map service based on middleware technology. Through systematic analysis of its basic principle and system architecture, this paper gives several optimization strategies. Finally, we make a performance comparison between tile map service middleware and traditional OGC (Open Geospatial Consortium, OGC) standard WMS service. Our experimental results show that the average response time of tile map service reduced by 46% than sending WMS request to WMS server directly, and the TMS middleware has a high efficiency when cutting map tiles dynamically because of its meta-tiling strategy. The study shows that tile map service middleware has important application value both in improving traditional WebGIS performance and in upgrading existing legacy systems.

Within a digital map service environment, the rapid growth of Spatial Big-Data is driving new requirements for effective mechanisms for massive online vector map tile processing. The emergence of Not Only SQL (NoSQL) databases has resulted in a new data storage and management model for scalable spatial data deployments and fast tracking. They better suit the scenario of high-volume, low-latency network map services than traditional standalone high-performance computer (HPC) or relational databases. In this paper, we propose a flexible storage framework that provides feasible methods for tiled map data parallel clipping and retrieval operations within a distributed NoSQL database environment. We illustrate the parallel vector tile generation and querying algorithms with the MapReduce programming model. Three different processing approaches, including local caching, distributed file storage, and the NoSQL-based method, are compared by analyzing the concurrent load and calculation time. An online geological vector tile map service prototype was developed to embed our processing framework in the China Geological Survey Information Grid. Experimental results show that our NoSQL-based parallel tile management framework can support applications that process huge volumes of vector tile data and improve performance of the tiled map service.

WMS (Web Map Service) is the standard that is formulated by OGC (Open Geospatial Consortium), and TMS (Tile Map Service) is the specification that is formulated by OSGeo (Open Source Geospatial Foundation), the objective of both are to realize the sharing and interoperability of geographical information, using those standards, we can build the network that is composed of distributed map servers, the client can use them to request layers from the server, so we can release remote sensing image data into WMS or TMS in order to realize the sharing of remote sensing information. Through the comparative analysis, the speed of TMS requests and generates layers is greatly faster than WMS, which has an important meaning for improving the response speed of the traditional WebGIS server and ameliorating users' experience, therefore, this paper mainly studies the segmentation and release of remote sensing images that are based on Tile Map Service (TMS).

Take open source GeoWebCache tile map service middleware as an example, through analysis of its basic principle and system architecture, this paper give three optimization strategies which are tile spatial index, extension mechanism and the deployment strategy. Finally, we make a performance comparison between GeoWebCache and traditional OGC (Open Geospatial Consortium, OGC) standard WMS(Web Map Service). Our experimental results show that the average response time of GeoWebCache reduced by 36% than sending WMS request to WMS server directly. The study shows that GeoWebCache middleware has important application value both in improving traditional WebGIS performance and in upgrading existing legacy systems.