NBN Co still doesn't know how more than a million analog-connected devices such as medical pendants and security alarms will continue to be supported when the Telstra copper network is replaced with an NBN fibre connection to homes.
There is no guarantee the telephone service provided by the NBN will provide end-to-end support for the devices. And there are no processes yet to ensure that when a retailer sells services to a customer, it is fully cognisant of any such legacy services and needs to ensure ongoing operation.
The termination boxes - the network termination device (NTD) - to be installed in all NBN-connected homes are fitted with two analog phone ports, known as Uni-V, and four ethernet data ports, Uni-D. Any alarm services would need to be provided as "over-the-top" (OTT) using one of the two Uni-V ports.
The industry is working to resolve the issues through Communications Alliance where an NBN OTT Services Transition committee has been set up.
Comms Alliance chief executive John Stanton said medical alarms were its first priority.
"There is a range of devices that sit on the top of the public telephone network now," he said. "They include security alarms, ATM machines and eftpos terminals. The medical alarm issue is the most pressing."
The alarms typically comprise a pendant worn by an elderly person, an auto-dialler and speakerphone.
"It is a complex matrix because there are many, many devices out there of varying ages and origins," Mr Stanton said. "Some of them will work absolutely fine through the Uni-V port or the Uni-D port [via an analog to digital adaptor and using a voice over internet protocol service], but not necessarily all of them."
The committee is working on a retailer guide that will set out protocols to ensure OTT services can be discovered and operational after NBN services are installed. He hopes it will be finalised soon.
The guide would "spell out the whole story of how these devices work".
"It will go to service providers and will be available to other stakeholders so that everybody has a clear picture as to what the situation is and who has responsibility for what," Mr Stanton said.
An NBN Co spokesman said a test bed dubbed the Plug Bench was being set up in Melbourne for suppliers to test their equipment on a range of NBN retail service providers. "We are making final preps and expect it to go live later in August."
But even when compatibility issues are resolved, customers could be hit with a bill of about $200 to connect the internal wiring of their old home telephone service to the Uni-V port on their NBN box, according to Phil Wait, chairman of the Personal Emergency Response Services Association.
"If they are not a voice-only customer and they want the Uni-V port connected to the house phone wiring, they will have to pay, and that is a couple of hundred dollars," he said.
PERSA is lobbying for this rule to be changed.
"It seems reasonable that if the government is going to take away your copper, then people that are reliant on devices connected to that copper need to have the service reinstated," Mr Wait said.