Triple Zero: Optus outage prompts changes to emergency service line

Article published 10 May 2024

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A report into last year’s Optus outage has recommended a suite of changes to ensure that Triple Zero can still be reached during a network disruption.

During the 12-hour Optus network outage last November more than 10 million mobile and broadband services were impacted. To make matters worse, around 2,700 people tried and failed to get through to Triple Zero to reach emergency services during the outage.

Following the outage, the Australian Government asked the former Deputy Chair of the Australian Communications and Media Authority (ACMA) to lead a review into this event and the resilience of Australia’s telecommunications network in general. The final report made 18 recommendations, all of which have been agreed to by the Australian Government. While the recommendations cover a range of issues, the report is clearly focused on ensuring that Triple Zero calls can be connected during an emergency.

What does the report recommend?

The report recognises that network outages are sometimes unavoidable, so most of its recommendations aim to reduce their impact and to ensure that network carriers like Optus and Telstra are accountable if and when outages occur.

In particular, it recommends that the Government establish a “Triple Zero Custodian” to oversee the Triple Zero system and make sure that it is always working. The report also recommends that network carriers be required to shut down their towers in the event of a network outage so that mobile phones can connect to another network to deliver Triple Zero calls.

This may seem contradictory. After all, if an aim of the report is to ensure that more Triple Zero calls can get through in an emergency, then why would it want fewer towers to be online?

This is explained by a process known as “emergency camp on”. If your mobile phone is unable to connect to your regular carrier because there is a network outage or you are in an area outside of your regular carrier’s network, you might notice a message on your handset saying: “no signal: emergency calls only”. In the event of an emergency, your mobile phone can use a different carrier’s network to connect a Triple Zero call, even if your regular carrier’s network is unavailable.

However, during the Optus outage last November, many people found that this “emergency camp on” process did not occur, leaving them unable to make Triple Zero calls on their mobile phones.

This is because some of the Optus 3G towers were still operational even though the Optus network itself was down. This meant that mobile handsets kept trying to connect to these Optus towers rather than connecting to Telstra or TPG towers instead. But without a working network to pass the calls through, the Optus towers couldn’t connect these Triple Zero calls to emergency services.

Triple Zero concerns may delay 3G shutdown

The Optus outage highlights another issue that advocates have been pointing to for a while. There are still plenty of mobile phones and other devices (such as some medical alarms) that rely on the 3G network in emergencies. With the shutdown of 3G on the horizon (or in the rear view in the case of TPG’s network), there are concerns that some people will be left unable to make Triple Zero calls, and that they may not realise it until they’re in an emergency situation. While Telstra has announced that it will delay its shutdown until August 31, the Government hasn’t ruled out stepping in to ensure that no one is left behind.

In the meantime, Telstra has set up a service for customers to check whether their mobile phone will need to be replaced. Telstra and Optus customers can check by sending the text message 3 to phone number 3498. If you are with another telco, you will have to contact your service provider directly.

In the midst of a cost-of-living crisis though, not everyone can afford to buy a new mobile.

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