A Successful System Architecture

Introduction
U S WEST has built a successful GIS system for outside plant engineering design named OSP-FM (Outside Plant - Facilities Management). OSP-FM stores the data for 500 wire centers (a wire center is a local telephone central office) and supports nearly 2 users per wire center. The OSP-FM system architecture must be very robust in order to handle the data volume and user volume, and still maintain acceptable application performance. The system that is in place today is highly successful, but it had to evolve to this level of efficiency. This document will show the evolution of OSP-FM, and the lessons learned during each phase.

A Brief History
U S WEST, like most other telecommunications companies that have been around for a long time, started with paper records of facilities that were hand drawn on non-standard maps and materials. As one might imagine, this is not an effective way to track billions of dollars worth of plant. U S WEST recognized this and when it became technologically possible to make this data electronic, U S WEST transferred the paper records to a CAD (Computer Aided Design) tool. For the time, this was a great advancement. The CAD tool allowed for all of the engineers to pull up any record that they wanted, at any time, just by pointing and clicking. Design engineers were now able to research jobs without shuffling through paper records, thus reducing cycle time and getting the customer phone service faster.

Although the CAD tool was a great improvement over paper records, there were challenges to overcome with the CAD tool. First of all, the data was not intelligent, nor did it use a database to store attribute data. There was no opportunity to automate engineering functions such as network trace. There was no method to enforce rules about concurrency either. If two engineers needed the same drawing, they could both get a copy and create conflicting changes, but the CAD system, like most CAD systems, would not catch the conflict. Another issue with the CAD tool was the hardware needed to store all of the drawings. U S WEST kept nearly every revision ever made to every drawing. This meant that for nearly every edit made to a drawing, a new copy of the drawing had to be stored somewhere (currently U S WEST has multiple terabytes of disk for these storage requirements).

U S WEST believed that a GIS system could solve these issues, and thus OSP-FM was conceived.