DIGITAL INTERCHANGE STANDARD

A Discussion paper by Michael Elfick - The University of Newcastle

Copyright M.H.Elfick 1996

The Mimaka Cadastral software can already read data from files produced by Civilcad, Landmark and ACS which are the three most popular software packages in use by surveyors in NSW. Of the remaining systems, Mimaka has worked with Geocomp and Foresight data in the past and Leica has promised full cooperation should we want access to Liscad files. Should any new systems come into the market in NSW, then they could either provide a facility to write data in one of the above formats, or provide details of their file structures so that the cadastral software can read their data.

The LTO could start accepting data in electronic form at any time provided that it is in one of the above three main formats.

There are several advantages in working directly with existing file structures rather than try to enforce another system on users.

• There is no great difficulty in using the files as they exist.
• The software suppliers are cooperative in giving details of their data formats.
• The software suppliers are very resistant to any idea of a new standard because of the considerable costs which they incurred as a result of the NCFF project.
• Users are also very wary of any new formats because of the failure of the NCFF idea.
• By using existing formats we can use directly the vast amount of data in electronic format currently held by surveying firms.

To facilitate interchange, instructions should be prepared to standardise details such as layer names, line coding etc., so that maximum benefit can be obtained from future data. This work should be carried out in close cooperation with survey firms so that procedures fit in with their normal methods of operation.

Data interchange has been looked at by Price Waterhouse as part of their study on the "Collection and Processing of Plan Information in Electronic Form", and they recommend that the new spatial data interchange standard AS4270 be used.

Detailed comments on the full report were sent to Graham Wallace in March of this year, with the following being my comments on the issue of a "digital interchange standard". Supplier Data Exchange Strategy.

The report based its findings on a sample of 85 surveyors and did not reference other published findings. Surveys by Prof Fryer in 1990 and 1992 provide a different picture and he had 444 responses out of 827 surveyors questioned. In many cases one response was sent from a survey firm for all the surveyors working there, therefore the real number of responses was probably higher than 444 and the results are from most of the survey firms in NSW. (see Australian Surveyor Vol 37 No 3 Sept 1992 pages 196 to 201.)