Internet Map Server (IMS) Technology
IMS technology, the spatial information published on the Net
is dynamic. The distribution of geographical information via
Internet allows the integration in real time of data originating
in any part of the world. The user has access to WWW resources,
moves freely through all the information with functional tools,
changes graphic representation online, links graphic elements
with information from databases, and works in real time with
options of exchanging, integrating, or analyzing data in a
new form through the network facilitate, expedite, and favor
the process of decision taking. Users can combine data and
information accessible via Internet with local data, see them,
and make consultations and the pertinent analysis.
distributive system of information, compared with tools that
are "stand-alone" or installed in a personal computer,
offers the following advantages, among others:
Sharing and exchange of data.
to applications and tools for analysis and decision taking
for a much more extensive public.
continued updating of information, helping to reduce redundancies
(duplications) and improving access to databases.
the updating of applications and disclosed information.
IMS architecture comprises three levels:
Work environment of the user. Any navigator that supports standard
HTML can act as client. It will also need to support Applet
(Plugin) of Java or ActiveX technology if the services being
accessed contain these components. Through Internet, and with
the navigator as interface, the Client sends requests to the
Server Application to obtain the information that the Client
wants to see, consult, or analyze.
Server Applications: These are responsible
for channeling and attending the operations that the user requests
on the data: ArcView IMS, MapObjects IMS, ArcIMS, MapGuide,
Geomedia, MMS, etc.
Databases: The server applications access
the data that can be stored in files or in spatial databases
(spatial data engine, SDE).
Land Use Project has researched the advantages and disadvantages
of the most important map server systems available on the
IMS (Environmental Systems Research Institute, ESRI),
(ESRI), and MapGuide
(AUTODESK). Other available systems for the spatial distribution
of data on Internet are GeoMedia Web (INTERGRAPH), MapXTreme
(OpenGIS Consortium) and GIS
Viewer (University of California, Berkeley).