Singtel landline outage caused by technical issue, failsafe backup did not activate: Janil Puthucheary

A recent hours-long disruption of Singtel’s landline services was triggered by a technical malfunction affecting a critical network component, Senior Minister of State for the Ministry of Digital Development and Information Janil Puthucheary revealed in Parliament on 11 November.

The incident, which took place on 8 October, affected emergency calls, healthcare institutions, and key customer service lines. Dr Puthucheary shared that the outage’s underlying cause appears to be a failure in Singtel’s backup systems to operate as intended.

The disruption impacted a network component in one of two systems supporting Singtel’s fixed-line voice service.

These systems, which are located at separate telephone exchanges, are designed with redundancy protocols allowing one system to manage the full load if the other fails. However, during this incident, the failover mechanism did not activate seamlessly, resulting in an intermittent service outage, according to Dr Puthucheary.

The landline outage interfered with calls to emergency services and other critical lines, including government agency customer service numbers, and led to widespread inconvenience. Calls to emergency hotlines, including Singapore’s 995 and 999, were among those affected.

As a result, the Infocomm Media Development Authority (IMDA) mandated that Singtel expedite restoration efforts, particularly prioritising government services.

During the parliamentary session, several Members of Parliament questioned the circumstances surrounding the disruption, sought information on preventative measures, and asked if any actions would be taken against Singtel for the service interruption.

Addressing these concerns, Dr Puthucheary clarified that, based on current investigations, no evidence links the incident to a cyberattack or sabotage. IMDA is continuing to investigate, ensuring thorough assessments of Singtel’s network stability and service resilience.

“The telecommunication network in Singapore is a key infrastructure that supports our nation’s connectivity needs and requirements,” Dr Puthucheary stated, underscoring the importance of IMDA’s role in holding primary service providers like Singtel to high performance standards.

As part of its regulatory duties, IMDA requires these providers to perform regular audits on network infrastructure, focusing on the security of network design, redundancy, and business continuity.

IMDA, Dr Puthucheary said, will take “strong action” if any lapses are confirmed, with potential penalties under the Telecommunications Act.

In response to a supplementary question from Member of Parliament Dr Tan Wu Meng (PAP-Jurong), Dr Puthucheary affirmed that Singtel, along with other service providers, is expected to maintain a high level of reliability under Singapore’s current regulatory framework.

Singtel previously described the October incident as “isolated” and noted that an estimated half of the calls made during the disruption were successfully connected. Full restoration of services reportedly occurred within four hours after the outage began.

As the disruption affected emergency hotlines, Minister of State for Home Affairs Sun Xueling informed Parliament that the Singapore Civil Defence Force (SCDF) and Singapore Police Force (SPF) took immediate steps to inform the public of alternative contact methods, including SMS numbers and the SGSecure mobile application, during the outage.

The public was encouraged to use these alternatives to reach emergency services until normal call functions resumed.

Responding to an inquiry from Progress Singapore Party Non-constituency Member of Parliament Hazel Poa regarding usage statistics for the alternative SMS numbers (70995 and 70999), Ms Sun indicated she did not have the requested figures but emphasised that the numbers were well-established, with prior efforts made to promote them.

In light of the recent outage, there will be a renewed emphasis on raising public awareness of these alternative methods of contacting emergency services.

IMDA, in collaboration with the Ministry of Home Affairs, SCDF, and SPF, will conduct an extensive after-action review to examine the reliability of emergency hotlines and to ensure that infrastructure and processes are equipped to handle future disruptions.

This review is expected to assess existing emergency protocols, identify potential vulnerabilities, and consider further measures to enhance the resilience of Singapore’s critical communications infrastructure.