THREE SIM cards from SingTel, StarHub and M1 were inserted into the iPhone 3G.

I tested to determine the download speeds available from the three telcos.

The tests were done around the East Coast area.

As a reference, the 3G network connection was switched off and I used a Wi-Fi connection to an 8Mbps ADSL router.

The website chosen was www.iphonespeedtest.com and I surfed on the built-in Safari browser of the iPhone. I executed the test by clicking on the Speed Test tab.

In fact, from postings on the site and results from our tests, Singapore has speeds comparable to Hong Kong and San Francisco for both 3G and Wi-Fi networks.

The Wi-Fi connection gave a very consistent reading, averaging around 450kbps.

Then, I tested the 3G speed. I switched off the Wi-Fi connection.

The SingTel 3G network averaged around 331.6kbps but there was a huge variation of speeds - from around 120kbps to over 460kbps.

StarHub's 3G mobile broadband network gave much more consistent results and nearly topped 400kbps, the best of the three telcos.

M1's download speeds were about half that of the other two carriers'.

I experienced little trouble using SingTel's (obviously) and StarHub's SIM cards. All I had to do was to insert the SIM card into the iPhone 3G, power up, and in no time I was surfing the Net.

Not with M1's card. The phone complained that it could not activate the cellular data network due to a PDP authentication failure.

After a bit of probing, I finally figured out that I had to specify the access point name (APN). From Settings, General, Network, Cellular Data Network, I had to change the APN to SUNSURF.

After that, I could surf to my heart's content on the iPhone 3G.

I conducted 10 tests because 3G signals vary from time to time depending on things like the number of people using the network.

The tests showed that the iPhone 3G can be used on all the three carriers' networks.

Results of the tests also demonstrated that StarHub's data download speed was the fastest and most consistent.

Images from SingTel took anywhere from four to 10 seconds to come in, which wasn't very fast.

From the tests, SingTel and M1 should open their bandwidth 'pipes' to allow faster data flow.

The iPhone 3G is a HSDPA (high speed downlink packet access) one capable of pushing data through at 3.6Mbps. SingTel is promising speeds from 1Mbps to 3.6Mbps.

It is not possible to get the fastest speed promised by Apple or SingTel because of the 'overheads' carried by the network.

The 'overheads' usually include some bandwidth reserved for redundancy and buffer which means that as you surf the Internet, the surfing will be smooth and you'll experience no lag. Also, as you move from one 3G cell to another, the data transmission will be smooth.

Do note that although the iPhone 3G can be bought from SingTel only, the SIM card can be used on StarHub and M1's 3G networks as well.

This story was first published in The Straits Times Digital Life on 27 August 2008.

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