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Data Sharing System for E-Government - IIMS Solution
Kenji Endo Basic Engineering Co., Ltd. 1) Takasaki East Tower 6F, 16-11 Sakae-cho, Takasaki, Gunma 370-0841, Japan Tel: 81-27-327-5431, Fax: 81-27-327-7415 Email: k-endo@basic-hq.co.jp Web: http://www.basicengineering.com Fuhu Ren 240-8211 Ackroyd Road, Richmond, BC V6X 3K8, Canada Tel: 1-604-214-1456, Fax: 1-604-214-1457 Email: fren@basicengineering.ca Web: http://www.basicengineering.ca 1. Information Integrated Management System (IIMS) Solution The Information Integrated Management System (IIMS) is a commercial off-the-shelf (COTS) product developed by Basic Engineering Co., Ltd. It provides a total solution through an integrated mechanism of catalogue services, metadata integration, distributive unstructured data management, security control and GIS data interoperability (Endo and Ren, 2001). IIMS unique concept for data sharing is based-on the service to integrate distributive and diversified data resources for distributive and diversified data applications. The basic considerations are as the following:
1.1 Catalog Services Catalog is to support organization, discovery, and access of data and information. Catalog services are one of the key functions for data sharing GIS. Because network GIS often links with vast amounts of Geospatial information resources, it is only through catalog searches that users can efficiently find the data suitable to their purposes. Without a catalog, it is almost impossible to locate the correct data, even when the data exist. IIMS provides catalog services through its metadata server that allows remote search on the metadata database and access distributive data linked with the catalog. The registration, editing and maintenance can be done remotely by data owners. The catalog services can be accessed through IIMS Java Client software, Web Browser, or IIMS Application Programming Interface (API). Figure 1 shows the main windows of IIMS Client for searching catalog and downloading dataset.  Figure 1 IIMS Client for Searching Catalog and Downloading Dataset 1.2 Metadata Metadata are data that describe the content, quality, condition, and other characteristics of GIS data. Metadata is very important for user to find, understand and process the shared data. Metadata are the core data in IIMS for search and understanding contents data. Depending on the type of the contents data, metadata usually contain the information such as title and keywords, abstract of contents, contact of author, spatial coverage, and technical information. IIMS catalog provides services to search and browse metadata. Since IIMS can host sharing of data in different formats, not limited to text data and databases, it is impossible to search through the data contents directly but must through the metadata. IIMS metadata are structured descriptive data over unstructured contents data for search and understanding the contents data. Metadata play the role as indexes for unified one-stop search to quickly find the accurate data of interest. Considering there are many metadata standards for different data types and resources, IIMS allows users to define multiple metadata models for different purposes. The metadata model can be a flat list, or hierarchical. Templates for popular metadata standards, such as the Content Standards for Digital Geospatial Metadata (CSDGM) by the Federal Geographic Data Committee (FGDC), are provided for user to easily configure their standard metadatabases. For each metadatabase, multiple views can be defined for search or quick catalog listing. Each view can contain full or partial metadata items in the metadata model. This feature allows users to concentrate on certain metadata items for convenience in different situations. The metadata for spatial location can be defined by points or rectangles. Index maps can be registered to such spatial items showing the location on a map or by collecting coordinates from a map. Word (or location name) lists can be defined for String or spatial items. Users can select a word from a word list for String items, or get the location of spatial items from a location name list. 1.3 Distributive Data Archive and Management IIMS provides services to manage distributive data and share the data anywhere and any time. Figure 2 shows a typical architecture of deploying IIMS in a multi-departmental organization for sharing data. Each department has an IIMS data server to store its valuable data, there is a metadata server hosted by information center that contains the metadata of all data for sharing in the organization. Data are still maintained and updated by each department in charge, internal users can access via LAN while external users can access through Internet.  Figure 2 Scenario of Application of IIMS in E-Government 1.3.1 Distributive data servers. IIMS Data servers are established to archive the data for sharing. Such data server can provide access services with proper protection and can be left in service all the time, while the data owner’s computer may be shut off or taken away when the owner is not at work. The storage space for both the owner’s computer and user’s computers can be saved, since they can access the archived data at IIMS data server when needed. Thus, they do not need to keep a permanent copy of data in their local computers (except if they want to save downloading time). So ideally, only one copy (besides the backup copies) of a dataset is needed. If all data are stored at a single server, when the data volume is huge, the performance would not be satisfied. If all the data are accumulated in a single server, when the data volume is huge or when massive users are concurrently accessing the data server, the server workload could be very heavy and so may become very slow. Distributive server systems can distribute the data accessing workload for better performance. When the disk is full, a single server system is difficult to be extended for more space. It’s almost impossible to host complete data resources accumulated in years of a huge organization by a single data server. In IIMS, new data servers can be extended at any time and anywhere to avoid this problem. There are also managerial issues. There are often issues about who should provide and maintain the data servers. In each department, there may be some sensitive data that must be kept within the department and shared internally. Data owner may worry about safety of storing its data to a data server of other department. In such cases, it’s not feasible to submit the data to the centralized server, but must be kept on their own servers. On the other hand, a department may not like to host data from other department at its own data server. When all data are stored in a centralized server, for security reason and managerial regulations, the server administrator may have to take care of the overall data input, updating and maintenance. Alone with the growth of the data contents, such work will become so huge and impossible to be done efficiently on time. With IIMS, each department or group can have its own data server(s) for storing its own data. IIMS metadata server just provides catalog service for distributive data instead of hosting actual contents data. The maintenance work can be shared by respective departments. Moreover, particularly for GIS, it’s often impossible to put all spatial data in different formats into a single database at one data server. IIMS provides registration and search services for various data servers that host data of different types and in different formats.
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