Oceanography 
Pests and diseases 
Physics 
Political science 
Population 
Recreation 
Remote sensing 
Sociology 
Soils 
Transportation 
Utilities 
Waste 
Water 
Wildlife 
Zoology 
Other 
4. METADATA DISSEMINATION AND 
MAINTENANCE 
Both simple and sophisticated software for the dissemination 
of metadata has been developed by a number of organizations 
and using a number of different approaches over the past few 
years. The type and method of metadata dissemination differs 
with the organizations needs, but in general, in countries 
where there is readily available access to the Internet, 
metadata access tools are provided using Internet protocols. In 
countries or applications where there is less access to the 
network, the software and metadata are distributed on rigid 
media such as floppy disk or CD-ROM. 
Figure 1 indicates the current thinking with regards to 
metadata database dissemination and maintenance. This 
structure allows for multiple users to access the metadata 
database search and query engine. It also allows the user to 
access numerous databases. These databases do not necessarily 
need to be in identical formats, however when the databases 
are not in analogous formats, this complicates the search 
engine software. 
à 
  
  
  
  
  
  
  
  
  
Metadata 
Database 
Engine 
A 
= | St 
Metadata Metadata Metadata 
Database Database Database 
  
  
  
  
  
  
  
  
  
Figure 1: System Structure for metadata dissemination and 
maintenance. 
4.1 Canadian Activities 
Several metadata standards have been developed that use the 
Canadian CGSB standard. These include the following. 
4.1.4 MetaView/GIS 
The Geographic Information Systems and Services Division of 
Geomatics Canada has developed the MetaView/GIS 
[EFFAO01] spatial browser for browsing and locating spatial 
data sets. The MetaView software tool provides a user friendly 
interface for searching and querying of a metadata base in the 
Canadian CGSB Metadata standard. The software is 
configured in the client server model to run over the network 
and the databases themselves can also be networked. 
One of the main differences between the MetaView/GIS and 
other directory services is the ability for the user to select data 
based on a region or area. This means that the software must 
have two databases, one which contains the metadata and the 
other containing map data. The system supports spatial queries 
from the global level to the local level using the map display. 
4.1.2 Data Catalogue Viewer 
The Manitoba Land Related Information System (MLRIS) 
which is sponsored by a number of Manitoba based 
organizations has developed a centralized Information Utility 
for managing spatial information. [LINNO1]. The MLRIS 
employs a Data Catalogue Viewer to allow the user to locate 
and select data for the users requirements. The viewer has a 
search engine, a browse capability, a keyword browse and a 
coverage browse capability. 
The Data Catalogue Viewer utilizes the Canadian CGSB 
metadata standard for storing and retrieving of the spatial 
metadata. The system also has some capability to disseminate 
spatial information as well. There does not yet appear to be 
any capability to store the metadata in a distributed or network 
environment (i.e. the metadata base is stored on a single 
system).Other capabilities for data security and maintenance 
are available. 
4.1.3 GCNet directory 
Geomatics Canada through the Canada Centre for Remote 
Sensing has developed a metadata browser for use across the 
World Wide Web [GCNEOI]. The user can use either an 
alphanumeric interface of a graphical user interface such as 
Netscape or Mosaic to access the system. The user can query 
for the location of remote sensing data and products in Canada 
and abroad. 
The GCNet directory service function does not use the CGSB 
standard, but it uses the International Directory Network 
(IDN) Master Directory (MD) developed by NASA. The MD 
is primarily used for describing remotely sensed imagery and 
is used in several countries and in many disciplines. The 
GCNet is coordinated through the Committee on Earth 
Observation (CEOS) group internationally. 
4.2 International activities 
Internationally, there are a number of directory services using 
various browsers, but these systems are not coordinated with 
respect to exchanging metadata between the systems. 
312 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B2. Vienna 1996 
  
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