The advantage of merging CAD and GIS
How a GIS creates an enterprise network model
The strength of a GIS is its ability to enter, retrieve, analyze, store and output spatial data.
Typically, 85'XOof the data in a telecommunications company has a spatial element that can
be tied to a geographic location. A GIS will work with vector data from a CAD system, but
it also allows the manipulation of giant arrays of integer and floating point raster data. This
allows the use of satellite imagery and aerial photos as a landbase, so GIS graphical data
representations are not a mathematical model as much as a graphic representation. The
capabilities of a GIS system lend more to the decision making process and long-range
planning. Ultimately, it deals effectively with the big picture.
For it to be effective, there can be no conversion process back and forth and neither the CAD
nor GIS software can have any element that uses a proprietary format, graphical interface or
database. If all data (graphics and attributes) are stored in an RDBMS such as Oracle,
Sybase or SQL server, and everyone is on the same network, data can flow through the
organization from one department to another regardless of the application software being
used. This means that demographics purchased and modified by the marketing group with
their GIS software can be shared with the engineers who can view the same data with their
CAD software.
There is no more duplication of databases with the uncertainty of which one is correct.
Current data stored in a common RDBMS that is shared with everyone in the company
means increased productivity and better customer service. In addition to the data integrity,
numerous applications can access and edit the data simultaneously.
An Example of Integrated CAD and GIS Data-
Use the GIS functionality to query the area in which he will be working: landbase,
facilities, customers, whatever is appropriate for the task..
- Using the CAD functionality, new poles, cable, facilities, customers, landbase elements,
etc. can be drawn or placed.
- At any point during the design process, when additional information is needed, simply
selecting the existing CAD element (a facility) will display all of the attributes in the
database pertaining to that individual item (a GIS function).
- Data analysis such as terminal status, pair availability, customer assignment, locations of
other utilities and any potential conflicts, etc. can be performed without leaving the desk
using GIS.
- Calculations such as "Loop Make-up" can easily be done with the GIS by retrieving data
from the database and then applying mathematical formulas from the CAD to determine
the resistance, dB loss, and the distance back to the Central Office.
- Bridged tap for a given pair can also be calculated (GIS function). And, if necessary,
displayed graphically on the screen to determine its location (CAD function). These
functions could not be accomplished on a conventional CAD system because of the
limitations of the non-intelligent entities in the drawing; they must be linked to the GIS
database.
- In addition, all of the facilities placed in CAD drawings can instantly update the
Continuing Property Records (CPR), assignment, joint use records and right-of-way data
when the work orders are posted "As-Built" in the GIS.
Conclusion
The real key to success is that everyone has access to the data. Low cost viewing tools are
readily available that can be customized to allow the user to do his job with little or no
training. By creating dozens of application-specific tools and propagating them throughout
the company, everyone becomes part of the team to help enter the data that will feed accurate
and up-to-date information to the entire organization.
When a company combines the functionality of a CAD and a GIS, the benefits are immediate
and far-reaching. The opportunities that this technological merger opens up are endless and
limited only by the imagination. Having a set of data utilized by many departments increases
data integrity, accuracy and workplace efficiency. This integration will open up new worlds
to a company and its customers.
