This article describes a problem faced when using the AirTel Prepaid Mobile Office monthly pack in Puducherry. The pack costs Rs. 375 per month but speeds are variable and very slow at times. What I know is that the speed change is not due to congestion. I suspect it is due to bandwidth throttling.

April 2007
6:50am: I wake up and think about checking mail. My favourite P2P client shows that speeds are good, around 10KB/s. But there is no guarantee with Mobile Office. Anytime, speeds can drop to 2-3KB/s.

I use a Class 12 GSM/EDGE data card for internet access on my laptop. It is the best GSM has to offer. At one time, I got 17KB/s (=142 Kbps) download and 10KB/s (80Kbps) upload which lasted for 7 days in December 2006. This is the capability of the card. You may want to check out a review on the Sierra Wireless AirCard 775 on my MSN Live Space.

So, hoping the good speeds will remain, I started checking mail.

6:59am: Speeds become an unbearable 2KB/s. I am unable to continue browsing. All browsers (IE, Firefox, Opera) show page not found.

7:25am: I quit my P2P application and am able to browse at very slow speeds.

What is interesting to note is that whatever speed change, it happens at the 59th minute. And it may happen at any hour, followed by good speeds after the same minute of the next hour (sometimes it may take more than an hour for speeds to return). Calling AirTel 121 is no use. They claim they offer speeds of 40Kbps (which works out to 40/8 = 5 KB/s).

Below in a snapshot of a graph from a P2P application showing the change in upload speeds. The change is abrupt and expected at particular times. This is different from the minor, often unnoticeable changes due to congestion.

Graph showing speed decrease

2KB/s = 2 x 8 = 16 Kbps
3KB/s = 3 x 8 = 24 Kbps
The signal bars are 5 bars out of 5 at all times.

Is this (16-24 Kbps) the unlimited internet which AirTel has to offer? This is way below the minimum speed (40Kbps) they claim to offer and therefore is a problem with their service. We need better quality of service (QoS).

I hope someone can give more information about this problem. Both AirTel technicians and users of Mobile Office are welcome to discuss this issue.