Computerized local PABX

Student: Michael Thomas Cowls

Supervisor: Dr. Mark Schulz

Category: Computer Systems Engineering Thesis Project

Even with the recent birth of the World Wide Web and other new generation digital communication techniques the public switched telephony network is still one of the most important communication systems in the world. The reasons for this lie in the two words public and switched. A public telephone network is one that gives anyone the ability to connect to it, and a switched network means that anyone can connect to anyone else.

This project incorporates the design, construction and simulation of a computer controller local PABX. The local PABX system is intended for simulation purposes and provides a number of user oriented features. The project is largely aimed at providing the foundations of a phone network and hopefully will form the basis for future projects, which incorporate more powerful features.

The final design of the switching centre supports up to four extensions. Each extension has its own interface board which handles the communication of non verbal phone data. The communication channel is implemented using analogue switching via an eight-way crosspoint switch to physically connect multiple extensions together. Being based around a PC allows the system to be very versatile and also allows for powerful software procedures to be implemented.

Some of the user features implemented in the local PABX include: Preferential Ringing, Conference Call (3 party's), Call Barring and Last Number Dialed.

Poster Presentation (PDF)

Thesis Document (PDF)