Recently, the Chief Directorate: Surveys and Mapping (CDSM) decided to migrate its 12 Laser-Scan LAMPS2 licences from Sun UNIX to Windows NT. It was planned that the LAMPS2 user workstations would move to Windows NT, but the LAMPS2 database would be kept on the UNIX server, due to its stability. In addition they also bought an extra three LAMPS2 licences. All 15 LAMPS2 workstations are to be used in their map production flow lines.

As part of the migration, CDSM purchased 15 NT workstations. Each workstation has an Intel-based CPU (Pentium III 600) with 256MB onboard memory. They also have integrated 4MB video adapters piping to 21-inch monitors.

Cross-platform communication (between UNIX and Windows NT) created a huge speed problem. After installation, the CDSM 'IT' division duplicated the 'working' UNIX-based LAMPS2 database onto an NT server. It was decided by CDSM, after extensive testing by them, that a single platform (Windows NT) solution gave much better performance than the cross-platform installation (UNIX and Windows NT). An Oracle ODBC client was installed on each of the NT workstations, which allowed the NT LAMPS2 workstations to read/write into the Oracle database. The Laser-Scan Data Access Manager (DAM) was installed on one of the NT workstations, to manage all connections to the NT LAMPS2 database. Essentially, this meant that all the NT workstations were able to access both the NT LAMPS2 'object-oriented' database and the Oracle7 'relational' database.

A number of benefits have resulted from the migration to a fully Windows NT solution. Firstly, performance gains "not even dreamt about prior to the upgrade" were immediately observed. The use of NT workstations has meant a significant speed increase compared to the previous UNIX workstations. As a guideline, a performance increase of over 500% was noticed when performing a screen re-draw. (Editor's note: To put the speed increase into perspective, the original hardware configurations comprised a server running at 167 MHz with 64 MB RAM and workstations running at only 110 MHz with 128 MB RAM. It would have been interesting to see what performance increase would have occurred had the CDSM upgraded to the latest UNIX systems.)

This speed enhancement has added to CDSM's productivity and helped increase quality assurance in their flowline. These improvements contributed to the already increased monthly map output by CDSM. Secondly, ease of maintenance is also a benefit, since all the PCs can be maintained in-house. Thirdly, user operation and training of new operators on the Windows NT platform will be easier, since the user in most cases is already PC literate.

All fifteen LAMPS2 seats are now fully operational on an NT platform, and ongoing maintenance is being provided by Racal Aviation Systems to sustain the successful implementation of this solution.

GIS & IT Division

Racal Aviation Systems

(021) 936 8100

gis@resa.co.za