Standards are needed for GIS interoperability between hardware, software and data. While some standards emerge through common use, organizations are working to develop national and international standards to address issues like portability, networking, common environments and development costs. There are various standards bodies and different types of standards including networking, database queries and data exchange formats. Implementing standards presents challenges like start-up costs, management support to adopt standards, and balancing functionality versus other considerations. More work is still needed on data standards including data models, resolutions, accuracies and ensuring data has sufficient documentation when transferred between systems.

2.  standards are needed as GIS users attempt
to integrate operations with other
hardware, GISs and data sources
 challenge is to get industry, government
and users to implement and promote use of
standards
 many standards are set simply through
common use, major attempts to develop
national and international standards

3.  portability of applications
 data networks
 common environments
 cost of program development

4. S TANDARDS ORGANIZATIONS
 American National Standards Institute
 Digital Cartographic Data Standards Task Force
 Federal Coordinating Committee on Digital
Cartography – Standards Working Group
 Institute of Electrical Electronics Engineers
 International Standards Organization
 Open Software Foundation

5.  Getting the Map into the Computer
Objectives

Maps and their attributes find their way
into GIS from existing data sources, from
converting paper maps or images into
digits, and from field measurement. How
data capture takes place has a major
impact on data structure, and therefore
use of the data in the GIS

6. T YPES OF STANDARDS
 networking standards – critical to allow
communications between remote computers
 database query standards – SQL is emerging as the
standard
 data exchange standards – governments/private
companies recognize need to exchange data
between different agencies/groups
 several common data exchange formats currently in
use:

7. D ATA EXCHANGE
FORMATS
 DEM – Digital Elevation Models
 allows a single attribute per cell

8. DATA EXCHANGE FORMATS
 DLG – Digital Line Graph
 most widely used format for
exchange of digital
cartographic data in vector
format
 used primarily for coordinate
information, though it does
support alphanumeric
attributes
DLG Roads

9. D ATA EXCHANGE
FORMATS
 Independent Map Encoding
 allows both coordinate and attribute GBF/DIME –
Geographic Base File/Dual data

10. D ATA EXCHANGE
FORMATS
 IntegraTIGER – Topologically ted Geographic
Encoding and Referencing
support pre-census
geographic and
cartographic functions in
preparation for the 1990
Census
to assist in the analysis
of the data as well as to
produce new
cartographic products

11. D ATA EXCHANGE
FORMATS
 SIF – Standard Interchange Format (Intergraph)
 popular data exchange format for many GIS packages
 DXF – Digital eXchange Format
 popular exchange format for many GIS packages to transfer with
CAD
 specially formatted text file that can be viewed and modified with
any text editor
 organized intdifferent sections – header, tableo, block , etc.

12. IMPLEMENTING STANDARDS
 Start-up Costs
 implementation of standard can incur substantial costs
(money and time)
 major short-term costs related to user training and
reprogramming software
 Management Support
 needs to recognize the positive impacts of standards
on productivity and system costs (plus commitment of
short-term costs)

13. IMPLEMENTING STANDARDS
 Technical Tradeoffs
 tradeoffs between functionality and performance
 standards provide for broad functionality
 adopting standard operating system provides access to large
library of existing applications
 standards do not allow fine tuning to specific hardware
 some de facto standards are neither efficient nor the
best available

14. IMPLEMENTING STANDARDS
 Potential for Security Risks
 wide availability of common operating systems allow
for misuse and exploitation
 spread of computer viruses depends on common operating
systems
 Innovation
 broadly accepted standards make it very difficult to
introduce innovations

15. S TANDARDS
 majority of standards
effort in GIS to date
has concerned data
formats
 missing – standard of data models that would provide
standard ways of representing geographic phenomena
 should there be standard resolutions for DEM?
 should there be standards of vertical accuracy?
 missing – standards of data accuracy for GIS
 map accuracy standards deal only with cartographic features

16. S TANDARDS
 data may be written into standard format for
transfer, but it may still be virtually meaningless
without extensive documentation
 standards would provide GIS user with
expectations about the reliability of the database
as a window on the world
 rather than on source documents, on
transferred databases

17. Maria Jorelyn T.
Laguilles
BSOA-4B