Telephone System Information

The main University PABX which services a number of campuses is an Ericsson MD110 PABX. PABX stands for Private Automatic Branch Exchange. The telephone number of the main University switchboard is +61 2 9351 2222. As well, the main PABX is connected to a number of smaller PABXs and other external systems via tie-lines.

The University of Sydney has been allocated all numbers of the form:

• +61 2 9351 xxxx
• +61 2 9036 xxxx
• +61 2 9114 xxxx
• +61 2 8627 xxxx
• +61 2 8628 xxxx

Here we treat the last 5 digits as the internal extension number on the University PABX. An extension is written as 16000 or 61234
Written in international format as the same numbers would be +61 2 9351 6000 or +61 2 9036 1234

So if your extension starts with a 6xxxx then you need to tell external callers that your phone number is 9036 xxxx
If your extension starts with 1xxxx then you need to tell external callers that your phone number is 9351 xxxx

Using special alternative forms of telephone numbers (such as tie-lines) saves the University money. Many calls which would normally be STD can be made without charge.

You need to dial the Tie Line number then pause for a second then last 4 digits of their number.
eg. 85 pause 1234

If you do not pause then the connection may fail.