Esri White Paper ● October 2003
Translation: lizard
2003
year
10
month
27
day
table of Contents
table of Contents
…………………………………………………………………1
Introduction ...................................................................... .2
Geographic information subsystem .............................................................. 2
Enterprise geographic information server ...................................................
Conclusion ........................................................................ 5
References .................................................................... 5
The translator: In fact, as a new information service system, this new enterprise geographic information server advocated by ESRI is a current popular B / S structure application in geographic information systems. As companies are increasingly complex, the C / S structure is no longer able to meet the growing software and business needs. The emergence of B / S is the structure of computer software development is also the result of the development requirements of the geographic information system for computer development.
Introduction
In the past 40 years, the Geographic Information System (GIS) has been implemented by each computer architecture (Coleman 1999). The earliest system is built and running on the frame and microprocessor, then the workstation, the next is the PC, and now the system design is recommended to use a distributed network (Peng and TSOU 2003). A new system is now surfaced, which is an architecture that runs in a central server environment and any device that can be accessed from the network. This white paper will describe this new enterprise geographic information server and implementation of the establishment of a true distributed enterprise geographic information system.
GIS subsystem
The geographic information system includes three main subsystems: drawing, spatial analysis (geoprocessing) and data management. A useful, GIS with general purpose, needs to be able to process all three aspects.
Three systems required by a mature GIS platform
The operation and visualization of geographic information is processed. In this subsystem, users can find map projections and benchmarks (Datum) conversions, maps to the page (Page, the translator thinks that the transformation, symbol model, map display, two, the transcription page used by the paper map) The interface frame of the geographic data of the dimensional design tool, edit control and map form.
Spatial Analysis Shenders Realize a series of functions such as two classic geographic operations - closer and superposed geographical analysis functions and data conversion function (input computer-aided design "CAD" data, output map, etc.), grid analysis (watershed model, Internal visual analysis, etc.) and 3D analysis (calculating slopes, orientation, etc.).
In the past few years, storage and management geographic information such as Access, IBM DB2, Oracle, and M $ SQL Server, such as M $, using non-custom commercial database management (DBMS) systems have become common experience. DBMS products can be used in GIS because they can allow users to create a single, centralized data warehouse (avoid redundancy and repetition), and they are widely used in GIS; they facilitate data sharing (by establishing the actual standard); support multi-user continuous geodatabase Edit; allow users to use DBMS backup and recovery tools. However, limited support and SQL access to advanced geographic data types (SHKAR AND Chawla 2003) are considering scalability - such as topology management, such as topology management (Hoel et al. 2003), The role of DBMS in GIS is re-test and stimulates the development of corporate geographic information services.
Three GIS subsystems can be implemented in a separate computer (single layer system), two computers (double-layer systems) or a large system, which is usually extended between these separate computers (three-layer system). At present, most of them have no exceptions, and the main GIS software systems are running on Microsoft Windows operating system desktops. In a single layer system, representative (user interface), business logic (geoprocessing function) and data management are always running in the same machine. Other extreme extreme cases, in a three-layer system representing a layer (including the mapping and spatial analysis subsystem), a client such as a desktop computer, the business logic of data access is running on a middle-layer application server, data management (DBMS) running on the server. This type of configuration, the client is quite mature and can include 100 megabyte data (CODE) in a advanced system (a so-called fat client implementation). This configuration has a good service for GIS users in the past decade and continues to analyze user services such as editing, editing, 3D modeling, and spatial analysis of advanced GIS tasks. However, in recent years, users require more maintenance work due to the lack of the client's cost and software. To maintain and update these broadly distributed PCs are very expensive - especially if (client) users do not do their own work, it is difficult to keep collaboration through a widely distributed organization. Single layer and three-layer information system system
Enterprise geographic information server
An alternative, more centralized architecture appears to solve these problems. The core of the new architecture is that the application server layer can not only include data management GIS subsystems, but also include mapping and spatial analysis subsystems. Running the GIS on a server means that the thin client can be used for the initial processing requests and display results. This concentrated GIS implementation can now refer to the enterprise geographic information server. They allow thin clients (web browsers) and fat clients (desktop GIS) with the ability to access data and processing through local or wide area networks. The server has two parts. Server Object Manager is responsible for the network's interface (such as web server) and to request a request information service container in the server to perform actual work. The two parts can be run on the same CPU, disperse on multiple machines (scalable -for scalability) or running on multiple CPUs running on the same machine. The server container obtains a data request to complete a data server (a DBMS).
Enterprise Geographic Information Server System
Enterprise Geographic Information Server has many ideal features as a distributed GIS user:
l Low cost maintenance costs. Since all data and processing are concentrated to a location, the costs required for maintenance and updates are minimized (such as software updates do not need to be performed on hundreds of PCs). The GIS server can be put together with other servers within the organization, so the same information technology employees can maintain them at the same time.
l Scale scalability. Additional resources can be easily obtained by installing new memory and disks or servers, but do not need to be shut down. In addition, the required resources are not expensive hardware but to handle, low, ordinary machine components.
l Based on standard data access and processing. Key factors using enterprise geographic information servers are their application programming interface (APIS), exposing all data and processing capabilities to all developers. This means that all users can access data and processing through any location. Key criteria include the establishment of a local area and wide-area network, establishing a local and wide area network Program Java and .NET. These standards provide a high-level application server communication adequate environment and establish a real business application. l Supports all key GIS data types and features. To deal with extensive users and applications, enterprise geographic information servers support all ordinary GIS data types and features. Supported data types include two-dimensional and 3D vectors, grids, labels, attributes, addresses, CAD, Memory Power and Calculation, Dimensions, Networks, and Topology. Functions lists include wide mapping, spatial analysis, and data management tools such as terrain and special map, editing, geocoding, network analysis, data management, 3D analysis, raster analysis, and geographic processing.
Enterprise information servers are suitable for simple and medium complex work that can be assured through network access. Typical work includes creating a user-specified topographic map; simple editing (such as Heads-Up, On-Screen Land Parcel Creation and Boundary Update, Or Changing The Attributes of Streetlights and Road Signage);
And select the shortest path for a number of delivery stations. A complex application that requires high interactive execution and expansion local processing is not suitable for WAN publishing and will continue to be implemented on a local computer such as desktop PC.
Enterprise Geographic Information Server is a good example of this new information system of enterprise application servers. Similar general purpose systems have been developed, these major developers have BEA (WebLogic), IBM (WebSphere), Microsoft (Windows Server), and Oracle (Oracle Application Server). They rely on and enhance DBMS capabilities to provide application development tools, web services, web service interfaces, and Scalability frameworks. In addition to GIS, many other applications are also implemented in this server. Corporate Human Management (Oracle, PeopleSoft and SAP) and customer relationship management (Microsoft, Pivotal, Siebel) systems are examples of central server applications.
in conclusion
Enterprise Geographic Information Server is a new type of GIS system that supports potential distributed users from a centralized location. This data management, application development, and data processing accesses based on industrial standards make it an ideal way to provide services to widely distributed users. Similar, low-cost maintenance, high scalability and excellent reliability mean that organizations can create convincing business cases, they will have a good return on investment. In the next few years, new GIS users will establish a system based on this new centralized server system, and many existing user organizations will also transform their existing systems to this system. references
D.J., 1999, "Geographical Information Systems in Networked Environments," in Longley, P.A., M.F. Goodchild, D.J. Maguire, and D.W. Rhind, Geographical Information Systems: Principles, Techniques, Applications, and Management.
New York
: John Wiley & Sons, 317-29.
Egnenhofer, M.J., 1992, "Why NOT SQL!" International Journal of Geographical Information Systems, Vol. 6, 71-85.
Hoel, E., S. Menon, And
S. morehouse
, 2003, "Building a Robust Relational Implementation of Topology," Proceeding of 8th International Symposium on Spatial and Temport Databases, 16 PP.
Longley, P.a., M.f. Goodchild, D.J. MAGUIRE, AND D.W. RHIND, 2001, Geographic Information Systems and Science.
New York
: John Wiley & Sons.
Peng, Zhong-Ren and Ming-Hsiang TSOU, 2003, Internet GIS: Distributed Geographic Information Services for the Internet and Wireless Networks.
Hoboken
,
New Jersey
: John Wiley & Sons.
SHEKAR, SHASHI AND SANJAY Chawla, 2003, Spatial Databases: a Tour.
Upper
Saddle
River
: Prentice Hall.
know how
This White Paper Was Created Using The Article, "
Enterprise
Geographic Information Servers, "Written By Dr. David Maguire for the Gis Development Magazine, Volume 7, Issue 8, August 2003.
