World GPRS subscriptions continue to grow

Wireless cellular network solutions have been around for many years but their adoption has been slow due to issues related to coverage cost, performance and secure remote access to business networks.

The deployment of the Global System for Mobile Communications (GSM)-based General Packet Radio Service (GPRS), however, has the potential to change this situation.

New statistics released by EMC, the world's leading provider of specialist market intelligence for the wireless industry, indicate that GPRS subscriptions continue to grow, quarter-on- quarter, although they still account for less than 1 percent of the world's GSM subscriber base.

The data shows an encouraging increase in the number of GPRS users, with 47 percent growth in the fourth quarter of 2002.

Since the first commercial launch of GPRS in June 2000, a total of 147 systems in 58 countries had been launched by the end of 2002, with 6.4 million subscribers.

The success of GPRS has been seen as a precursor to the uptake of data services and beyond to 3G. The industry as a whole is watching the progress made by European and Asian operators launching GPRS services.

Although initial adoption was perceived to be limited by the lack of handsets, with more than 45 devices on the market from all major vendors, this can no longer be seen as a hindrance to success. Operators are now putting their faith in color devices and further messaging services, but the real driver must be desirable, consumer-based applications.

Not surprisingly, Western Europe dominates the GPRS landscape, accounting for 51 percent of networks launched by the end of 2002.

According to the study made by Dell Computer Corporation, GPRS provides faster data transfer rates, "always-on" connection, robust connectivity, broad application support and strong security mechanisms.

GPRS currently supports an average data rate of 115 Kilobytes per second (Kbps), but this speed is only achieved by dedicating all eight time slots to GPRS. Instead, carriers and terminal devices will typically be configured to handle a specific number of time slots for upstream and downstream data. For example, a GPRS device might be set to handle a maximum of four slots downstream and two upstream.

Under good radio conditions, this yields speeds of approximately 50 Kbps downstream and 20 Kbps upstream. This is more than three times faster than current 14.4-Kbps GSM networks and roughly equivalent to a good land line, analog modem connection.

The aggregate cell site bandwidth is shared by voice and data traffic. GPRS operators will vary in how they allocate the bandwidth.

Typically, they will configure the networks to give precedence to voice traffic; some may dedicate time slots to data traffic to ensure a minimum level of service during busy voice traffic periods. Unused voice capacity may be dynamically reallocated to data traffic.

With its faster data transfer rates, GPRS enables higher- bandwidth applications not currently feasible on a GSM network.

An "always-on" connection eliminates the lengthy delays required to reconnect to the network to send and receive data. Information can also be pushed to the end user in real time.

GPRS allows providers to bill by the packet, rather than by the minute, thus enabling cost-effective "always-on" subscriber services.

GPRS also improves data transmission integrity, through a number of mechanisms. First, user data is encoded with redundancies that improve its resistance to adverse radio conditions.

If an error is detected in a frame received in the Base Station Subsystem (BSS), the frame may be repeatedly retransmitted until properly received before passing it on to the GPRS core network.

Like the Internet, GPRS is based on packet-switched data. This means that all native IP applications, such as e-mail, Web access, instant messaging, and file transfers, can be run over GPRS.

In addition, its faster data transfer rates enable GPRS to accommodate higher-bandwidth applications (such as multimedia Web content) not suited to slower, GSM dial-up connections.

GPRS is particularly well-suited for applications based on the Wireless Application Protocol (WAP). WAP has gained widespread acceptance in a new breed of microbrowser-enabled phones.