MultiLine is a digital trunk telephone service providing maximum functionality for larger offices with digital PABX systems. It provides primary rate ISDN voice services, with each connection supporting between ten and thirty trunk lines, and is available in formats complying to the Austel standard TS014 or ETSI TS038 common channel signalling protocol. Optus MultiLine is available in most CBD, metropolitan and major regional locations. Analogue services are also available through Optus’ Directline product.

Features & Benefits
Directory and Emergency Services Listings	A basic White Pages directory listing for each of your MultiLine services, unless you have specified for your service to be a Silent Line. A single ‘main number’ will be listed for each Optus MultiLine service. All service numbers and address details are also forwarded to the Integrated Public Number Database used by Emergency Services, in accordance with ACA regulations1.
Hunt Groups	Specify how your inbound calls are to be forwarded to various phone lines within your business.
Battery Backup	If you have network termination equipment at your premises, battery backup ensures continuity of service in the case of site power outages (in accordance with the ACA/ACIF standard S002:2001). Battery backup units are dimensioned to provide 2 - 4 hours of backup.
Malicious Call Tracing	A Malicious Call Trace feature allows you to activate an alarm signal to the exchange during an unwelcome call. The Optus exchange records details of the unwelcome call, including a party number, and Optus can arrange for a letter to be sent to the originator of the unwelcome call or initiate further action.
PABX And Modem Interworking2	MultiLine will interwork with PABXs complying to the TS038 (ETSI) and TS014 (Australian) ISDN DSS1 signalling protocols. Optus MultiLine can also be used for modem calls.
National 64k Data Calls	Optus MultiLine services can be configured to provide a limited National 64kbps data call facility, to support requirements such as videoconferencing and inter-PABX signalling. This data call capability has the following characteristics: Characteristic Capability Information transfer capability Unrestricted digital information Transfer mode Circuit mode Information transfer rate 64kbps (nx64 ‘MultiRate’ values not supported)

^ Optus MultiLine is available to customers in an Optus Network area. For technical and commercial reasons not all business can be connected to Optus MultiLine.
1. This database is used by Emergency Services to identify the originating location of any 000 calls made from any telephone line.
2. Specific configuration parameters for interworking with PABXs may be specified in the application form for your MultiLine service, including the number of digits sent by the Optus Network to the PABX (default 10), and whether the PABX requires the exchange to provide dial tone or ring tone (default no tones provided).