Quick Guide to Types of Business Phone Line Services


We Have Your Business Phone Lines Covered

Apart from mobiles, there are essentially four types of business phone line services available to businesses. As technology has advanced, some of those will soon be obsolete.

PSTN Copper Lines

PSTN (Public Switched Telephone Network) is also often referred to as POTS or Plain Old Telephone System. This is the traditional copper network that's being gradually phased out with the introduction of NBN. Although still in use by a lot of businesses, PSTN lines are old technology that's being superseded by IP telephony. As Australia’s broadband infrastructure is rolled out, PSTN lines will be decommissioned and services transferred to digital lines and sip trunks.

PSTN lines don't require a telephone system and are often used by smaller businesses or as standalone lines for EFTPOS, Fax or delivery of a DSL service.

ISDN2 Digital Lines

ISDN2 is digital network technology that can carry voice and data services in a digital format over PSTN lines. It enables two (2) concurrent telephone calls at the same time over the one PSTN line. ISDN2 is mainly used by smaller businesses that require 2 to 4 telephone lines and need access to digital line features like direct in-dial numbers for their PBX extensions. As businesses gain access to better quality broadband services, it's expected that most ISDN2 users will migrate to IP telephony and sip trunks.

ISDN2 lines require a telephone system fitted with a BRI (basic rate interface) card and line rental is quite expensive compared to ISDN and SIP Trunks.

ISDN 10-20-30 Digital Lines

ISDN (Integrated Services Digital Network) is a form of digital network technology that enables multiple concurrent telephone calls using the one PSTN line. Essentially, this is a form of IP telephony where a special data connection is used to deliver telephone services using the existing copper lines. There are two main ISDN networks in Australia, Optus and Telstra. Although the technology is pretty much the same, there are some differences. The main one being that optus multiline is available in increments of one call lines (ISDN channels) over and above the first ten. Telstra’s ISDN is only available in blocks of ten i.e. ISDN 10, ISDN 20, and ISDN 30.

ISDN lines require a telephone system fitted with a PRI (primary rate interface) card and come with high end features and functions such as extension level billing and multiple direct in dial numbers.

Business VoIP SIP Trunks

Business SIP Trunks and IP telephony are really the new age business phone lines. SIP (Session Initiation Protocol) is a means of delivering telephone services over the internet. In common terms, SIP Trunks are essentially business VoIP (voice over internet protocol) lines and allow you to make and receive calls over a broadband internet connection. Similar to ISDN services, you can purchase blocks of in dial numbers that can be attached to the SIP trunk number, effectively giving you a range of direct phone numbers that outside callers can contact you on. These are usually allocated to individual PBX extensions so that outside callers can call directly rather than go through the main number and the reception.

IP Telephony and SIP Trunks require an IP phone to operate and are the ideal replacement for traditional telephony and ISDN services. Recent improvements in Australian Broadband Infrastructure and access to high quality broadband services mean that businesses can now take advantage of this powerful and highly flexible technology.

To find out more about the type of business phone lines available at your premises, please contact one of our Business Consultants on 1300 000 300 or CLICK HERE to make an online enquiry.

Request ComCheck

Upgrade to the Latest Technology


Need More Information? Call us on 1300 000 300 and talk to one of our Business Consultants. They'll be able to review your requirements and suggest the best possible phone line service for your business.

Enquire Now