It's hard to believe but SingTel's phone network went down for at least 7 hours yesterday. Apparently, only those who are on the 3G network were affected. Those on 2G phones were not. According to SingTel, the system was down from late morning to 5pm yesterday. The official response from SIngTel was: "We apologise for any convenience caused by the intermittent interruption in our 3G service yesterday. We had advised some of our 3G customers who were experiencing difficulties in making and receiving mobile calls to manually select and switch to our 2G/2.5G network on their mobile phones. Our 3G service was back to normal at around 5pm yesterday.


However, one user told me he still could not receive calls when he switched back to his 3G network this morning. I asked SingTel and the mobile operator said it was checking on this. I called 1626, SingTel's help line, and heard a message that it was experienceing unusually high call traffic (11.30am).

And this isn't the first time this has happened. The user also complained of a similar problem at the end of October this year. I verified with SingTel and it said in an email response to me: "Some 3G customers might have experienced difficulties in making and receiving mobile and data calls last evening. This was due to a service disruption caused by a fault with our network interface cards at one of our exchanges. Service was back to normal by the same evening."

According to the aggrieved user (I am not on SingTel for the record) who spoke to me, he said the problem with the downtime was that it doesn't show on the phone. The handset actually displays that there is a signal connection, but he started scratching his head when his usually hectic ringing days were unusually devoid of calls. He solved the problem by forcing his phone to switch down to a normal 2G network. What was even stranger, according to my source, was that SMS and Internet worked fine. but calls could neither go in nor out.

I am no expert on base stations and base station controllers, but from the little I know there is always some form of redundancy when it comes to mobile networks. This is a huge embarassment for Singapore which has always prided itself on being one of the most wired nations in the world, and our top-class connectivity is one of the key factors for attracting foreign investors to come here and do business. I remember that IDA (Infocomm Development Authority of Singapore) has some form of 99.9 percent network uptime for the telcos here. Again, I'm not an expert with these numbers, but one day or even half a day in 365 days amounts to 0.14 percent already!

IDA needs to look at this downtime very seriously, and SingTel and the other telcos need to look at their 3G infrastructure carefully, especially M1 which is rolling out HSPDA. Singapore cannot afford to lose its reputation like this.