I purchased an Airtel Wireless USB Modem last week for a whooping Rs.5700. Practically, I had no other choice as I didn’t have Airtel’s DSL service in the area I live in and BSNL had a wait time of nearly 2 months. (when will the incumbent telecom service providers learn that service not provided on time is service lost). So, I bought the Airtel USB Modem and subscribed for the unlimited data plan (Rs.999 + taxes). My experience with the modem is as follows:

Configuration: The box comes with the required CD and installation of the software and the modem is a breeze. Absolutely no problems at all with the installation. It takes about 24-48 hours to get the SIM card activated, but once that is done there is no problem with the installation or modem connectivity.

One potential problem that I envisage with users having an USB based “Active Key” to connect to their VPN networks is that, they won’t be able to use both the USB ports for the modem and this leads to a significant drop in speed.

Connectivity: I have been using this modem for nearly 10 days and there hasn’t been a single instance when the modem has refused to connect or dropped the connection. So, as far as uptime and connection reliability is concerned, the modem is wonderful. Even on the move the modem operates without any issues.

Speed: Browsing seems to work reasonably well, but still far slower that what my 128Kbps DSL connection could achieve. But, so far browsing has been restricted to text sites and I haven’t even ventured into viewing videos on youtube etc. So, I don’t have much idea about how the browsing experience will be on media content.

The highest download speed I have managed so far is only 2.4KBps (19.2Kbps). I have tried using the modem at different times to check if there is significant difference in speed, but so far I haven’t been able to observe much difference. 2.4KBps is the fastest I have been able to get so far. This is as pathetic as it can get.

The wireless modem works on Enhanced Data Rates for GSM Evolution (EDGE) protocol for data transmission. By theory EDGE should be able to support upto 236.8Kbps on the 4 Receiver (Rx) timeslots. Airtel provides 4 Rx timeslots and 2 Tx timeslots and theoretically 296Kbps (236.4Kbps Rx and 59.1 Kbps Tx) can be achieved (Airtel only allows for 5 slots to be active at any time). That is nearly 44Kilobytes/sec. This is tremendous speed and if even half of this is achieved then the experience can be really good. But, what I have got so far has not even been 10% of this speed. Actual data rates will be much lesser than the rates mentioned above as these rates include the security data, CRC’s and the FEC’s transmitted. So, even assuming that only 70% of the mentioned speed is what is possible for actual data transmission, the data rates that I have got are bad.

Also, when the software is installed and the connection is established, a box will pop-up near the system tray and say “Connected at 230.4Kbps”. Don’t get happy seeing this box as it is talking about the speed from the UART to USB. The serial port is operating at the max. speed of 115baud and I think they are using 2 bits per symbol for better speeds. (Baud is different from bit rate).

All in all, I would say that it isn’t worth nearly Rs.6000. Buy this modem only if you need connectivity on the move and there is absolutely no other option. Reliance is another provider who is offering wireless data cards/modem, but I haven’t been able to find much info about their service so far. And a couple of friends who use the Reliance connection have been facing connectivity issues. So, if connectivity is the biggest driver then this modem is a worthy investment. If you wanna just browse the web then I would suggest that you look for other options.