This fancy new digital network is called GSM - Global System for Mobile Communication, and its technological backbone of choice is TDMA(similar to FDMA).The radio frequency band utilised by GSM is the 900MHz spectrum and later introduced on the 1800MHz band.
- Digital encryption (64bit A5/1 stream cipher)
- Packet data (used for MMS/Internet access)
- SMS text messaging
- Caller ID and other similar network features.