At that point, I tried to make a phone call. The call was connected. But shortly later, I lost signal again. Then it came back again. The SMS text message was still unsuccessful. Mobile broadband Internet surfing did not work. Other people have reported a combination of various problems.
In general, things seemed to have gone back to normal by about 19:40. But I’ve just noticed right now as I type, already after 21:00, that my phone can’t pick up a 3G connection. There is a normal GSM (2.5G) connection, but no go for UMTS (3G). I gave up waiting to speak to a person at 1626; I imagine the hotline must be overwhelmed from customer calls.
We are definitely quite dependent on mobile phone networks. A downtime like this causes great inconveniences. It might have been worse considering if you had to make an emergency call, and the call could not be connected.
It’s scary to think about disruptions to critical infrastructure. A fire at a substation in Somerset Road can somehow cause over-voltage conditions in several areas around Singapore. An outage at one data centre in Singapore can cause massive disruptions to many online government systems. Are we getting complacent about the availability and robustness of our infrastructure?