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E-Biz-Leveraging the Web
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Internet GIS solution for Bermuda’s Environmental Health Department
Distributing SNB data across the internet
As mentioned earlier, UNB and Service New Brunswick signed a data sharing agreement in
which SNB would provide its data (e.g. DTMs, property and topographic maps) to the UNB
campus body for academic and research use. UNB proponents of this agreement believed that the
best and simplest way to make the SNB data available was via the Web.
Issues associated with developing the data download site
UNB’s technical staff responsible for the development of the SNB data distribution site faced the
following challenges in providing this information to their students and staff:
- Allowing students access to the data in a timely manner - Most of the computers at UNB
share a 10/100 MB connection. In many cases, 30 – 50 computers share a single connection,
which means that during periods of peak usage the data transfer rate across the network for
these computers is very slow. Thus, the limited bandwidth usually available to students
necessitates a lightweight solution for quick navigation and data selection.
- Minimizing the number of support requests to its technical staff - Since many of the
students/staff that will access the data are GIS neophytes, the support staff for this Web site
could easily become overwhelmed with GIS related questions. It was believed that the staff
would receive questions associated with:
- understanding the data – e.g., What are the features contained in the dataset(s); Is there
any metadata associated with the dataset(s), etc.;
- using the data – What are the steps necessary to import the dataset into a GIS; Is it
necessary to configure the GIS to use the data, etc.
- understanding the file(s)s that were downloaded to their desktop – What do each of the
files downloaded to the desktop represent (a SNB file is actually a .zip file that contains
12 different files); and
- downloading the data – What are the steps necessary to download a dataset(s);
- Allowing students to access data across different computing platforms, some of which may
not support the latest Web Mapping technology. - The different computing platforms at UNB
include UNIX based computers (e.g. Sun workstations), Macintoshs and PCs (running
95,98,NT, 2000 and Linux).
- Protecting the data against both (a) unauthorized access – that is, access of data by someone
outside the university; and (b) unauthorized use – that is, use of the data in a manner
contravening to the Conditions of Use Agreement signed between SNB and UNB.
- Providing an intuitive system that leverages the latest Web Mapping technology - Web
mapping products provide many capabilities that would assist users in selected dataset(s)
associated with their study area. Since UNB has a Campus Wide Site License with ESRI, the
development team believed that they should make use ESRI’s Internet Mapping System
product ArcIMS.
SNB Data Download Site
After analyzing the challenges associated with providing UNB’s campus body access to SNB
data, the developers designed the site to meet several characteristics, including:
- Data download page is not directly accessible from the main page - The user must click
through several information pages before arriving at the data download page. These
information pages describe, for example, the naming convention of the SNB files and the
file(s) that is actually downloaded to the client’s desktop (Figure 1).
- Provide tutorials that illustrate, in detail, the procedure necessary to get the data into a GIS
(both CARIS and ArcView) (Figure 2);
- Provide tutorials that illustrate, in detail, the procedure necessary to customize the GIS to use
the data (both CARIS and ArcView) – Customizing is necessary to ensure that the data is
displayed using the correct symbology;
- Provide on-line examples of the data so that users can visualize what the planimetric files and
the DTM files contain;
- Allow users to download data using two different methods, a GUI (Web Mapping
Application) method and a non-GUI (simple HTML/text) method; and
- Compel the user to both accept a Conditions of Use agreement and enter a valid UNB User
Name and Personal Identification Number before allowing the user to download the data to
their desktop.
Figure 1 illustrates an excerpt from the Web page describing the contents of the SNB file that is
downloaded to the client machine. Figure 2 illustrates an excerpt from the tutorial for importing a
SNB topographic file, downloaded from the site, into CARIS. The senior author in consultation
with students, who had been using the data to complete their course assignments, developed this
tutorial. This tutorial was designed to eliminate questions regarding the step necessary to both:
(a) import the data into CARIS; and (b) configure CARIS to draw the data using the correct
symbology.
The two methods available for use for downloading SNB data – that is, non-GUI (simple
HTML/text) method and the GUI (Web Mapping Application) method - are now described.
Figure 1. Extract from the Web page describing the contents of the downloaded SNB file
Figure 2. Excerpt from the tutorial for importing a file from the SNB topographic database
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