Fast, cheap, mobile access

Aiming for a budget conscious market that requires faster than dial-up or ISDN Internet access, the Duxbury USB EDGE modem is also highly mobile.
Read time 4min 10sec

The introduction to the local market of high-speed downlink packet access (HSDPA) technology by mobile network operators MTN and Vodacom has highlighted the GSM network as an alternative way to access the Internet.

With initial download speeds of 1.8Mbps, HSDPA offers faster than ADSL access to the Internet, but as a 3G technology, HSDPA still has limited building penetration and coverage.

However, HSDPA is not the only way of tapping into the benefits of Internet access using mobile phone networks.

At download speeds of 270Kbps, enhanced data rates for GSM revolution (EDGE) technology offers faster than dial-up or ISDN Internet access with all the mobility offered by the GSM network. However, EDGE comes without the technical limitations or initial and running costs of 3G and HSDPA.


Duxbury Networking has developed a series of GSM modems to meet the demand for mobile Internet access that connects to desktop and laptop computers via serial ports, USB ports and PCMCIA slots.

Perhaps the most versatile is the USB modem, providing Internet connectivity to a wide variety of computing devices. It`s a neat, compact device that easily connects to any USB port using the jointed USB connector supplied with the unit.

The modem and accessories neatly pack into a case that comes with the unit, making it easy to slip into a laptop bag for on-the-go Internet access.

My only complaint concerns the rather fiddly cover for the SIM card slot. It tends to fall out easily and it is rather difficult to slide into place correctly.

Otherwise the modem is easy to use and the accompanying software fairly simple to install. It also has a reasonably user-friendly interface for managing connections.

The modem comes with an extension cable and stand equipped with a suction cup to enable positioning for optimal reception. A hands-free kit for voice communication is included in the package, enabling the modem to double up as a rudimentary phone, which is useful for topping up airtime and purchasing data bundles.


Unlike 3G, wireless broadband, and WiFi hotspot connectivity, GSM modems provide Internet connectivity wherever there is cellular coverage.

With the mobile network operators claiming EDGE coverage of about 97%, an EDGE modem effectively turns most of the country into an instant wireless hotpot, although there are areas where access will be limited to the much slower GPRS data rates of 115Kbps.

MTN offers better EDGE coverage than Vodacom. Various data bundles are available at a cost of between R1 per MB of data for smaller bundles and R0.50 per MB for larger bundles. However, there is a catch.

At present, MTN`s data bundles may be purchased only every 30 days. If data needs are underestimated, users will automatically start paying R2 per MB without the option of purchasing a new data bundle before the end of 30 days. If needs are overestimated, data bundles not used in the 30-day window will be lost.

The convenience of a GSM modem is unquestionable, but the cost-effectiveness of using such a device is open-ended. It depends on a variety of factors, including usage patterns and the ability to estimate data usage with absolute accuracy.

Moderate Internet users are likely to be on the winning side, considering a GSM modem eliminates the need for an Internet service provider (ISP) because it connects directly to the Internet. Also, only data is paid for, and not the time spent connected, which eliminates additional telephone costs and makes things like online banking much less stressful.

At the very least, a GSM modem provides a useful backup to all fixed-line access to the Internet and once integrated into surfing patterns, users are likely to be lost without it.

On the downside, a Web-based e-mail client will have to be utilised, and the GSM modem cannot be used for Skype or any other voice over IP applications on the MTN network, which was the only one used for testing. Vodacom EDGE was not available in my area.

EDGE GSM modems are likely to appeal to anyone needing flexible Internet access away from the office environment, users requiring backup for fixed-line access, or users who require faster than dial-up access in areas where ISDN or ADSL connections are not available.

Dial-up users with only one telephone line will also appreciate the ability to surf the Internet without blocking incoming phone calls.

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