classification 
By exchange of geographic information it is 
important that sender and receiver have the same 
perception of the physical world. If e.g. you want 
to exchange data about a lake it is important that 
you have the same perception of what a lake is, 
and why it cannot be e.g. a water hole. 
This is why the classification of the physical world 
plays an important role when stipulating standards 
for exchange of geographic information, ie. 
establishing codes and belonging descriptions. 
What is being exchanged? 
During many years it has been possible to exchange 
drawing data as well as data between CAD/CAM-systems. 
It is here a question of "exchange of drawings" with 
importance to colour, line-type and symbols. These stan- 
dards for exchange are all international and colloquially are 
called "drawing formats". 
Of current interest is e.g. the following: 
- IGES system independent standard 
- HPGL a drawing standard developed by Hewlett 
Pachard especially for drawing machines 
- DXF a CAD/CAM standard developed by Auto- 
Cad 
- STEP a new system independent standard. 
Today it is however also necessary to exchange data 
between geographic information system attaching the 
greatest importance to the exchange of coherence between 
data. So far, there are no international standards within 
this area, but a lot of national ones. 
- Denmark has the DSFL-format 
- Norway has SOSI (Standardisert Opleg for Stedfæstet 
Information) 
- Sweden has ISOK (?) 
- Finland has EDI (Electronic Data Interchange) 
- England has NTF (National Transfer Format) 
- USA have SDTS (Spatial Data Transfer Standard) 
- NATO has DIGEST (Dlgital Geographic information 
Exchange STandard) 
and there are many more. 
Work is going on to develop an international standard in 
this field, but instead of developing a common standard at 
a technician level, the struggle, at present, takes place by 
means of lobbyism in the fine corridors in Strasbourg and 
other places, where the different interested parties try to 
promote their own national standard to become an interna- 
tional standard. 
E.g. the following proposal for a common European 
standard has been put forward - EEC and all that talk of 
the free market in 1992 - and there is a striking similarity 
between the letters "NTF" and "ETF": 
101 
  
  
  
  
  
  
  
  
  
  
  
  
Frankfurt Leipzig 
Ax Belfast 
ATKIS NÜNTE. 
Dublin 
Jp 
Bonn N A si 
ETF 
Lyon Conenh 
M. PP x e agen 
EDIGEO SS DSFL 
Marseille 
- s 
Paris Aalborg 
A Proposed European Transfer Format (ETF) 
At present there is a struggle between the English format 
NTF and the NATO-standard DIGEST, which i.a. is 
heavily supported by the French. 
What next? 
Time will show "who the winner is", but we certainly will 
have an international standard. Until then, i.e. for the next 
5-10 years, we can use our national standard, the DSFL- 
format, which compared with other national standards is a 
very well-developed standard. The force of the DSFL- 
format is that it is a "de facto-standard", developed by a 
group of interested parties, independent of the system 
suppliers. The format has since 1982 been developed 
quietly, only influenced by the users wishes, and the 
individual user has always had a "short way" to the working 
group, who delevops and maintains the DSFL-format. 
Short about the DSFL-format 
When, in the beginning of the eighties, the DSFL-format 
was "designed", the object describing data model was 
chosen, i.e. what you wanted to exchange was descriptive 
data about physical objects in nature. This "perception of 
the world" has later become the "truth", and it is probably 
the reason why the DFSL-format "is still going strong". 
The leading principle of the DSFL-format was originally: 
  
Main information 
  
  
Object code 
End