SINGAPORE - Mobile users of M1 woke up yesterday to an outage that lasted over five hours and affected voice calls, texting and mobile-data services.
Preliminary investigations into the disruption, which started around 7am, suggested an issue with a call-processing software.
This had unexpectedly prevented users' devices from registering on its mobile network, M1 said. Services were restored at 12.15pm.
Apologising for the inconvenience, M1 chief executive officer Karen Kooi said the telco will be offering one day of free local mobile calls, local SMS and MMS on Sunday.
M1 said it tried to get services back up quickly, but the complexity of the network required troubleshooting of numerous interlinked network entities.
The telco explained that it had recently made significant investments to upgrade its mobile network by incorporating several new network entities and advanced software features, which increased the network's complexity.
The Infocomm Development Authority of Singapore (IDA) said yesterday it was "concerned" about the incident, in the light of other M1 disruptions in the past year.
IDA said it will be carrying out its own investigation before determining the appropriate course of action.
In January last year, M1 users were hit by a massive disruption lasting up to 71 hours. The telco was fined $1.5 million.
Ms Jenny Lee, 31, head of logistics and operations at a beer company, said yesterday's disruption affected her sales orders as she was unable to reply to inquiries promptly. "I increasingly work on the go, and need reliable data for e-mail and WhatsApp," she noted.
Communications executive Brandon Tan, 33, said he is considering switching telcos, but doubts if it will make a difference. Noting that there are only three players - the other two being SingTel and StarHub - Mr Tan said "local telcos are not forced to be competitive enough".
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