Telstra has been threatening to do it for years but it appears that this time ISDN will become a thing of the past in about 2 years which is a similar timeline for European and US telcos. As a technology, ISDN has had a pretty good run being introduced to Australia in 1988 as the original overlay network that was phased out in 2000 after the introduction of the current ETSI standard in 1997 – about a 30 year lifespan.
We have been advised that in June 2018 sales of new ISDN services will cease and all ISDN services must be migrated to an alternate service by September 2019. Similar shutdowns have occurred in the past with such services as analogue indial, meter pulses and removal of answer reversal off analogue lines.
The alternate service is going to be some form of SIP line most probably delivered over the NBN. This presents some issues with the phone system. Many perfectly good phone systems do not support SIP lines directly or only intended it to be used to connect to a larger central system so some form of converter is required. Various converters are available however we don’t recommend them because once the phone system is updated, the expensive converter is no longer required. Our approach is to use a suitably configured phone system as the converter because this allows a slow migration by adding phones to the converter system until eventually all your extensions are on the new system and the old one can be decommissioned. This generally results in minimal redundant hardware in the converter system.
Telstra offers converters with their SIP Connect service to connect to older phone systems but at present SIP Connect has to be delivered over a Telstra circuit.
What will be the benefit of migrating?
Primarily, cost. SIP services tend to be cheaper to rent and calls are much cheaper so overall savings are 30 to 50%. Many providers offer capped price calls that offer considerable savings over the ever increasing price of ISDN services.
The other main benefit is flexibility. Conditional failover is a feature of ISDN whereby if there is some problem at the main site, calls can be redirected to a backup site with ISDN but a SIP service is much more flexible because it only requires an Internet connection to be active – even a 4G mobile data connection will do in an emergency.