NTT Docomo faces fresh reliability questions after two major 5G-SA disruptions. Both incidents hit Japan within five days. They affected voice, messaging, and data services for hours.
The failures centered on congestion in switching equipment. This equipment helps route traffic across standalone 5G services. Standalone 5G uses a dedicated 5G core. That differs from older deployments using 4G network support.
The first disruption happened last Friday. Services remained unstable or unavailable for almost 14 hours. About 1.5 million dedicated 5G-SA subscribers felt the impact. Regular 5G users, 4G customers, and MVNO users avoided the outage.
Then, another disruption struck on Wednesday. It lasted around nine hours and affected the same service group. NTT Docomo said it found no evidence of unauthorized access. It also found no signs of a cyberattack.
However, the root cause remains unclear. Early signs point toward a possible software issue. The affected switching platform may involve equipment from Ericsson, based on earlier supplier disclosures. Still, NTT Docomo has not confirmed that link.
The situation highlights a difficult reality for advanced mobile networks. Standalone 5G can deliver lower latency and better service control. It also supports future enterprise and industrial use cases. Yet, it adds new operational complexity for telecom teams.
For operators, this means reliability must match innovation. Customers expect modern networks to work without interruption. Engineers must detect traffic congestion before it grows. They also need faster recovery processes when core systems fail.
NTT Docomo’s network problems arrive during wider regional scrutiny. Singtel recently received a 1 million Singapore dollar penalty. That followed outages affecting 600,000 customers in March. A failed cooling system caused overheating and network shutdowns.
Australia has also faced serious service failures. Telstra and Optus experienced outages affecting emergency call access. Those incidents caused public anger and regulatory pressure. They also raised questions about emergency network governance.
Meanwhile, NTT Docomo faces another separate crisis. Its online store suffered a cyberattack. The breach exposed private data from around 300,000 customers. CEO Yoshiaki Maeda apologized last Friday for both issues.
The company continues to investigate the incidents. It may also compensate affected users. That step could help rebuild trust. Yet, stronger transparency will matter more.
For telecom professionals, the lesson is clear. 5G-SA networks bring powerful capabilities. But they demand rigorous testing, monitoring, and incident planning. As networks evolve, resilience must evolve with them.
