Business Phone Lines

What is PSTN?

PSTN stands for Public Switched Telephone Network. PSTN lines are also sometimes referred to as POTS (Plain Old Telephone Service) as they are the most basic form of phone connection available. Our PSTN lines are delivered over the Telstra copper network. PSTN lines are analogue connections which are run over a twisted pair of copper wires between the telephone exchange and your business.

PSTN lines are the most common form of phone line connection in Australia. Almost every home with a phone line will be using a PSTN line and the majority of businesses will have at least one PSTN line also. PSTN lines are essential for services such as ADSL, Eftpos, alarm monitoring & fire lines.

What is ISDN2?

ISDN 2 is a digital service that replaces a conventional analogue PSTN telephone line with 2 digital ISDN2 lines and was formerly known as OnRamp 2. ISDN (Integrated Services Digital Network) is an end to end digital switched network capable of carrying voice and data traffic. Before ADSL internet was introduced, ISDN was used to achieve greater internet speeds over dial up. Now ISDN is primarily used by businesses for voice calls.

ISDN 2 services are known as Basic Rate Access (BRA) and have two information channels (B channels) and a control channel (D channel); aka ISDN 2B+D. Each B channel transfers data at a rate of 64 kbps and can be used together to provide a combined bandwidth of 128 kbps. The D channel carries data at 16 kbps but effectively has a much lower available bandwidth as it is reserved for monitoring the B channels and for configuration of the service.

ISDN2 is delivered over the Telstra copper network and is available nationwide within serviceability parameters. Factors restricting the delivery of ISDN2 include transmission loss due to distance from the customer premises to local telephone exchange, local infrastructure shortfall and capacity at the exchange.

Benefits of ISDN2

• Proven Technology – Used in Australia since 1989 and fully adapted to today’s business requirements
• Reliable – Highly stable, end-to-end, direct digital connection to the exchange ensures crisp, clear calls.
• Widely Available – Reaching 96% of the Australian population using Telstra’s national phone network.
• Direct In Dial – 100 consecutive phone numbers that can be used for advertising purposes or for calling directly into extensions.
• Scalable – Easily add additional ISDN 2 services, adding pairs of channels to accommodate for growing businesses.