Web-based GIS
New means to access spatial information
Gilles ALBAREDES
Autodesk Europe, Middle-East, Africa headquarters
20, route de pre-bois
Case Postale 766
CH-1215 GenevaSwitzerland
Tel: + 41 22 929 75 45
Fax: + 41 22 929 75 01
E-mail: Gilles.albaredes@eur.autodesk.com
URLs:
http://www.autodesk.com
http://www.mapguide.com
Difficulty in accessing information can be a barrier to efficient decision making. Geomatics has long been seen as a significant improvement in providing access to information with a spatial component. However, usability problems combined with the cost of implementation and the lack of data have prevented GIS to be used as a corporate tool for faster decision making.
Emerging technology referred to as Web-based GIS is bringing new dimension in accessing the information. Relying on the intra/internet network protocols, Web-based GIS allows for sharing spatial information among a virtually unlimited number of users.
This paper will provide a brief history of GIS and its evolution from both a technological and a usability point of view. The second part of this paper will introduce the concept of Web-based GIS in parallel with more standard IT trends. Finally, a number of case studies will be presented, including the use of Web-based GIS in a geopolitical context, a municipal context as well as a transportation management context.
In conclusion, this paper will demonstrate the growing interest of the internet for geomatics and will attempt to highlight the key evolution of geomatics for the future.
INTRODUCTION
There have been numerous attempts to understand the limitation factors of the proliferation of GIS within the enterprise. There is indeed a clear disconnect behind the argumentation justifying the use of GIS and the actual situation. When considered, the argument that states that 80% of decision making includes a spatial component should yield the wider corporate use of GIS. In reality, the use of GIS is typically restricted to specialized departments. Enterprise-wide access to the data generated by GIS is seldom. Several reasons can be given to explain this dichotomy between theory and reality. These can be related to the misunderstanding of GIS by most top managers, the corporate policies preventing the sharing of information or the technological barriers. Nevertheless, inside and outside the boundaries of an organization, the need to communicate geoinformation to a wider audience is increasing. Collaborative work with subcontractors dispersed geographically is a good illustration. In the field of land survey, surveyors, local authorities, national cadastre agencies as well as property management firms, legal advisers or notaries rely heavily on the exchange of spatial information. Extrapolating from this, the need to provide spatial information to the general public is also increasing sharply. Municipalities are slowly understanding the need for remotely accessible electronic map-based public services. In the tourism industry, remote and wide access of spatial information represents a key asset. Taking into account these changes in user demand, this paper will focus on the introduction of new network-based GIS technology that will greatly facilitate the proliferation of GIS.
THE EVOLUTION OF GIS TOWARDS WEB-BASED GIS
In the early 70’s, GIS was initiated as a leading-edge technology, not a communication vehicle. This can be surprising to any geographer like myself who has been taught about the visual communication of maps in their educational courses. However, until recently, very little focus has been spent on the sharing of geoinformation. Rather, most efforts went towards improving the technology itself, as an isolated tool. For long, GIS suppliers and users have been concentrating their efforts towards successful implementations. The prevailing philosophy was that GIS must be at the core of the enterprise, and that the enterprise must adapt to GIS. This was very much an elitist view of GIS which was highly arguable. This view was driven by technology and not by usability considerations. The concept of ‘enterprise-wide GIS’ emerged in the early 90’s. It began to be a well understood theory accepted by a large number of actors. However, in practice it met all kind of barriers. Often, internal user policies prevented this concept to become a reality. The ability to share data across departments was viewed by a number of users as an unbearable change in behavior. For some, it could represent a loss of power. In these cases, the well-known principle ‘information is power’ could summarize the reasons for the slow introduction of enterprise-wide GIS. But it is fair to say that corporate policies and behaviors were not the only limitations. The technology itself was also a significant limitation factor. It usually consisted of cumbersome client-server technologies, difficult to implement, difficult to maintain and not cost-effective. Because of these issues, very few implementations of enterprise-wide GIS have succeeded. For the few that did, it often yielded two difficulties. First, the corporate processes had to be changed in order to adapt to the introduction of GIS. Secondly, the access to geoinformation was not granted to all actors, but was still limited to a selected number of professionals.
The introduction of the internet has dramatically improved the situation. Originally conceived as a global communication tool based on text, the internet has evolved into a true multimedia global communication network. When restricted to the enterprise, the Internet has become a common infrastructure generally referred to as the Intranet. When extended to the enterprise and its partners (i.e. sub-contractors or dealers), the Internet is rapidly being implemented as the Extranet. Text, images, sounds, and numerous type of files can be shared via the internet. One of its key advantage is that it is relatively inexpensive to operate and it relies on well defined standards. The development of the internet has developed unequally around the globe. North-America is clearly leading the game. In Europe, Northern-Europe has developed a strong infrastructure and is ahead of Southern Europe. Japan and Far-East Asia are still behind. Despite these differences, there is an obvious move towards the same direction; internet has become a priority for most nations, and is playing an increasing role in their economic and social fabric. The internet is also a well-respected means to facilitate the development of emerging and developing countries. In Eastern-Europe for instance, the internet is now widely used and is helping to ease the integration of countries like Poland or the Czech Republic with the rest of Europe.
DEFINITION OF WEB-based GIS
Digital maps could be characterized as being a type of computer files, easily transferable via the internet. It is obviously a bit more complicated as digital maps have a number of unique properties:
They are usually large in size. For instance, the Canadian street map is a 1.5 Gigabytes200 megabytes file.
They are composed of intelligent objects. These objects can encapsulate behaviors and information. The tight relationship between graphical objects, their behaviors and attribute information is critical.
They are not standard. Digital maps can have different file formats and internal structures.
Web-based GIS have recently been introduced to the market. The principle of these systems is relatively straightforward.
Web-based GIS rely totally upon the internet technology. One of their strong points is that they do not depart from the standards in place in this domain. Typically, their architecture include 3 software components:
Server software: Combined with standard WEB server and database technologies, it will monitor all network transactions, access to the databases, security environments, compression-decompression processes.
Author software: it is used to prepare digital maps for their wide access. In particular, it defines the association between the geographical objects and the zoom/pan factors. It also define the user environment and is a key tool to optimize the usability of the GIS. Finally, it defines the structure of the data and the access to databases.
Viewing software: Combined with standard WEB browsers (i.e. Netscape Navigator or Microsoft Internet Explorer), it provides the user interface to the end-users. It can be a plug-in or Active-X control. In any case, this software must be as small as possible in size to allow an easy download. A typical size would be one megabyte. New technologies such as Java-applets allow the direct access to the server without requiring this piece of software. This is interesting although today it can slow down performance for a number of operations.
The general architecture of a Web-based GIS does not differ from any WEB technologies. It relies on existing standards and it is based on the ‘thin-client’ concept. One advantage is that it provides wide access to complex geographical databases to anyone equipped with a standard PC, Windows, and a Web browser. It goes several steps further than displaying digital maps as graphic entities. It allows access to multiple databases in a distributed environment. More importantly perhaps, it can provide geo-processing tools such as querying, spatial analysis, polygon processing to numerous distant users. One important principle is that the data remains on the server and is not physically transferred onto the viewing systems. This prevents unnecessary duplication of data which often results in a management nightmare. Also, Web-based GIS facilitates the maintenance of the data since it can be centrally maintained.
TYPICAL CONFIGURATION OF WEB-BASED GIS
A number of GIS suppliers are now providing different flavors of Web-based GIS. These can be classified into 3 main categories as follows:
Image viewing: A number of systems are providing snapshots of the central geographical database. First, an abstract of a digital map is selected by the viewer based on a generalized small scale overview map. Once the area of interest has been selected, the system creates a raster snapshot of the original data. The duplicated data is then sent via internet to the requester. This mechanism has the advantage of being straightforward and provides relative fast responses. One key disadvantage is that the system duplicates the data. When the central data is modified, modifications are not signaled to the end-user until a new snapshot is created. Another limitation is that the data accessible by the end-user looses its intelligence. Objects behaviors and links to the attribute tables are typically lost. This prevents the use of the data for spatial querying and analysis. Finally, the accuracy of the original data is lost when the original data is transformed into pixels. This can be a problem for large scale maps.
Internet compliance: A number of systems rely on making existing Desktop GIS compliant to internet. With this approach, the end-users will benefit from a familiar environment. The other advantage is that the existing data files can be used as such. The internet access is granted for the original digital maps without any file format transformation. A key disadvantage is speed. Unfortunately, traditional GIS file formats have been designed for desktop systems, not for intensive network transactions. Consequently, these formats are not suited for the internet and do not allow a fast transfer of the information. Typically, Internet compliant GIS are fine as long as the user relies on small data sets. These systems do not allow the transfer of larger data sets in good conditions. Most users will face performance issues with these systems.
Internet GIS: The latest generation of Web-based GIS have been built from scratch to take profit of the latest innovation of the internet. Several features characterize them. First, they rely on the transformation of the original files into specific formats for the internet. These formats can vary. All of them allow the transfer of the original vector data without rasterizing it. The accuracy of the original maps and their cartographic representations are then both preserved. Secondly, object behaviors and link to attribute tables are maintained. Finally, these new formats compress and structure the original data to optimize performances. A good illustration of Internet GIS is Autodesk MapGuide from Autodesk Corporation.
IS WEB-BASED GIS AN ACCEPTED TECHNOLOGY?
Generally speaking, the use of Web-based GIS is still in its infancy. However, both from a technology and a corporate policy standpoint, there is great hope that this technology will rapidly emerge as a standard. There are a number of early challenges that need to be resolved in order to exploit its full potential.
Organizational matters at the user site can slow down the acceptance of Web-based GIS. A number of departmental GIS users may consider that their autonomy is at risk. In most organizations, Internet-based technology is often controlled by the Information Technology department while historically, operational departments have often defined their GIS strategy in relative isolation. The introduction of Web-based GIS will undoubtedly modify roles within the organization. One widespread belief is that this technology implies GIS databases to be managed centrally. In this scenario, each department would possibly lose control over their own departmental databases. On the contrary, Web-based GIS should allow the use of distributed databases. Each department can therefore keep control over its own data, while the central system manages the access to this data. Even with a geographically dispersed organization, the underlying internet technology allows the access and combination of each remote data sets. For instance, each thematic layer of a digital map could be a data set maintained on PC’s located in different offices. Web-based GIS bypasses geographical distances and departmental structures.
These is still a visible resistance to internet among a number of GIS users. Because the typical data sets produced by GIS are large, and composed of complex data, a number of GIS users believe that performance will be a problem. Very much like Windows versus UNIX in the early 90’s, a strong debate is emerging regarding Desktop versus Web-based GIS. It is true that today, only a few Web-based GIS can handle realistic GIS data sets. As discussed above, selecting the right technology is important. Web-based GIS must utilize dedicated internet related technology associated with state-of-the-art compression and data optimization algorithms. When built for the internet, Web-based GIS will allow fast transfer of data. As a good illustration, in the WEB site found on http://www.mapguide.com, the end-user can access and manipulate nine gigabytes of geographical data without problems. With time, most systems will comply to performance improvement and the network bandwidth will also dramatically improve. Difference of performance between desktop GIS and Web-based GIS will disappear.
Copyright of data over electronic networks is still being determined in most nations around the world. A number of National Mapping agencies are in the process of issuing policy documents on the use of their data in Intranet and Internet set-ups. But we are far from a clear guideline. The danger is that the legal aspect of dissemination of geographical data over the Internet is defined in isolation from any other areas, such as the publication of books, videos, songs or software. A global legal framework is requested. In the meantime, pilot projects are taking place to demonstrate the data security model of Internet/Intranet mapping and to undertake some analysis on the charging models which could be put in place. One of the most advanced prototypes in Europe is the Terra Bavaria project led by Wenninger and the Bavarian Land Survey Agency. The combination of electronic commerce software and Web-based GIS is being tested for the on-line commerce of Bavarian topographic maps. It is clear that in this context, the selected Web-based GIS must include strong security capabilities to protect the data owner against data piracy.
EXAMPLES OF ON-GOING PROJECTS IN EUROPE
In Europe, an increasing number of initiatives can be seen in difference sectors.
In the geopolitical domain, the United Kingdom election brought to light an interesting project. Web-based GIS was used to facilitate the access of the results of the election to the constituents. Thematic county maps were created and symbolized according to the local electoral results. These maps were posted to a WEB site which was promoted by the national press. As a result, 3.5 million access to the site were logged. The night of the election, more that 500,000 users connected and browsed the maps on their PCs. This large scale projects showed the clear benefits and power of Web-based GIS where any digital map can be made accessible to a large number of users. More importantly perhaps, these users could also query and process the maps to derive more intelligence out of them. The WEB site is still live and can be visited at http://www.elections.co.uk.
Another interesting project is in the area of Air Traffic Control. Based in Brussels, Eurocontrol is a European agency that supervises the air traffic control over the European sky. Among other tasks, this organization is responsible to create and maintain the air traffic control charts. This is done centrally in Brussels (Belgium). Web-based GIS is of interest to them for ultimately share these maps with the national air traffic control agencies. Prototypes are under way. In less than ten man day, this institution was successful in posting gigabytes of their digital maps to the internet. Another example of geoinformation dissemination is the experience initiated by SIGnet, a French start-up company. They use Web-based GIS to sell aerial images covering the whole of France. Their site can be seen on http://www.signet.tm.fr.
In the area of transportation, highway management companies are increasingly interested in the use of Web-based GIS. A good example is Autostrada del Brennero (Italy). Traffic conditions can be mapped centrally and communicated via the Intranet for departmental use as well as remote office use. In time, a public site should allow the display of traffic condition maps and should allow better trip planning. Railway companies are combining Web-based GIS with Global Positioning Systems (GPS) to monitor their train engines real time location on the rail network. A prototype can be see on the following WEB site: http://www.gridnorth.com/tracking.
A number of large municipalities across Europe are currently prototyping Web-based GIS for two primary goals. First, they want to share their digital maps across departments on their Intranet. Significant cost savings can be seen from the prototypes. Work processes can also be improved. Their second goal is to create a public WEB site allowing the access of a certain category of maps and related information to the constituents. For instance, land survey, land use and recreational areas maps can be made public. A few municipalities are in the process of automating the building permit process. The objective is to create an online permit request system, allowing constituents to go through the whole process from their home PCs. Prototypes for the city of Rome (Italy) can be visited at the following WEB site http://www.romaonline.net or the city of Berlin (Germany) at the following WEB site: http:// www.net-map.com.
In the natural resources and environmental control sectors, Network GIS proves to be a useful tool. A good illustration of its use is by the Canadian Ministry of Fisheries and Wildlife who is using Web-based GIS to monitor and communicate wildlife sightings on the island of Vancouver (Canada). An illustration of their site can be see on http://gridnorth.com/ecology. Similarly, the Geological Survey of Canada uses Web-based GIS for integrating and distributing its vast amount of physically diverse data across government agencies and to the end-users. The whole of Canada geological map is accessible on http://www.gridnorth.com/geology. In Europe, within the EC funded project called E-MAIL (Environmental Management Architecture for Information Delivery), a consortium of organizations develop Internet-based applications relying on Web-based GIS. These applications are designed to support decision-makers within (regional) public organizations in the environment sector. The E-MAIL applications will support these users in environmental monitoring and planning by using data captured from different sources. The objective is to provide the users with an efficient support for obtaining in-depth information on key environmental topics and environmental indicators. These include for example, population and dwelling census, urbanization and sustainable development planning, actual and potential ecological risks, surface and ground water quality, water resources management, defense from flash-floods, habitat management/conservation, waste management, pollution and industrial risks, relevant sites to be monitored.
In the engineering and utilities world, Web-based GIS is being investigated for improving collaborative engineering within the organizations and with the sub-contractors. One of the largest telecommunication operator in the US called Sprint is currently deploying Web-based GIS to monitor their facilities location. Their WEB site can be visited at http://144.223.86.81/SEGIS. Sprint has now the system that delivers maps over their Intranet so that everyone can share the benefits. It is designed is such a way that it can be used by external organizations as well, like their real estate division. Sprint goes one step further in utilizing this technology for creating a check request or invoice approval online which is tightly integrated with their on-line GIS.
Finally, Web-based GIS is being investigated in the field of geo-marketing. SRC (http://www.sbponline.com) is promoting Web-based GIS for marketing. Until now, desktop mapping solutions prevailed in this sector. The benefits of Web-based GIS facilitates the use of third-party data without owning it, just by ‘leasing’ its use. The success of this principle is highly dependent on the on-line accessibility of the geo-demographic as well as customer profiling databases. In the education, a good example of the use of Web-based GIS can be found with UNIGIS. As a distant teaching institution for GIS, UNIGIS needed a GIS accessible from a variety of locations. In some of their educational institutions, they are now using Web-based GIS as a teaching tool.
CONCLUSION
Web-based GIS applies to many industry. Early examples of the benefits of this technology proves that the use of Intranets and Internets will empower more people to rely upon geoinformation. Technology is definitely moving the right direction. The use of third party data with these systems remains an issue to be resolved. But above all, Web-based GIS brings new perspective for the use of GIS. With time, it will become a standard tool, used by professional as well as casual users. It will finally help positioning electronic maps as a stronger communication vehicle as well as a better decision making tool. The proliferation of GIS is dependent on the widespread acceptance of this technology. New policies must be rapidly put in place to allow the data suppliers to fully benefit from it.
Gilles Albaredes is a geographer by education. He studied quantitative geography at La Sorbonne, Paris (France) and successfully conducted a Master of Science (Msc) degree at the University of Alberta (Canada) under a Canadian scholarship. His Master’s thesis developed new location-allocation algorithms applied to a French rural area.
In the mid-80’s, Gilles Albaredes integrated the GIS laboratory of the French Defense Mapping agency and was affected to a scientific mission that dealt with the integration of emerging GIS technology. Following this assignment, he joined ESRI-France in Paris and co-started this office. Gilles Albaredes further developed his career by undertaking international assignments with Unisys and Intergraph. In 1996, he joined Autodesk, the 5th largest PC-software vendor in the world. He is currently Autodesk’s Director for its GIS Market Group over Europe, the Middle-East and Africa.
Gilles Albaredes is a French Citizen aged 34, who lives in Geneva Switzerland, is married and has two children. He is fluent in English and has given numerous papers in GIS European events.