A Brief History

The very first mobile networks were analogue systems and extremely primitive when compared with modern networks, lacking even basic privacy and therefore making eavesdropping trivial. GSM (2G) saw the introduction of digital voice and with this came encryption, followed soon after by short message service (SMS) and narrowband packet data services (GPRS).

3G networks brought numerous improvements and not least of which much higher data rates, which continued to increase with later releases and the advent of High Speed Packet Access (HSPA).

What do we mean by releases?

The 3rd Generation Partnership Project (3GPP) was established in 1998 to develop the standards for UMTS (3G) mobile networks and has since gone on to define 4G and 5G standards, with work currently underway to develop the specifications for 6G. Each mobile network generation spans a number of 3GPP releases and these are incremental updates which introduce new functionality, higher data rates and support for new frequency bands.

2G and 3G networks provide direct support for voice calls and SMS via circuit-switched technology. However, this mode of operation was dropped from 4G networks onwards — which are purely packet based — and instead the IP Multimedia Subsystem (IMS) is used to support native voice and SMS. 4G and 5G networks can also be configured to where available “fallback” to 2G and 3G networks for voice/SMS, but this means operating multiple networks in parallel.