Second Generation

The second generation (2G) cellular networks were designed as digital instead of analog. Global System for Mobile Communications (GSM) became the leading 2G cellular system. GSM radio resource control protocol is used over the radio interface between Base Station Controller and mobile station for radio resource management. The first General Packet Radio Service (GPRS) networks entered commercial use around 2000, when the first GPRS mobile stations became available. The mobile stations were GPRS‐enabled mobile phones, network cards that could be installed to computers, or personal digital assistant devices supporting GPRS packet data connections. GPRS introduced a new mechanism, referred as packet data protocol context, to manage the packet data protocol flows and related tunnels. Enhanced circuit switched data brings new modulation and line coding methods for GSM circuit switched data bursts. The new methods support improved data rates up to 43.2 kbps per timeslot.