GSM (Global System for Mobile Communications)
- Most popular standard for mobile telephony systems, originated from Groupe Special Mobile
- The ubiquity of GSM enables the international roaming arrangements among mobile phone operators.
- Both signaling and speech channels are digital, and thus GSM is considered as 2G mobile phone system.
- GSM standard benefited customers the ability to roam and switch carriers without replacing the hand sets and network operators.
- GSM implements low-cost implementation of Short Message Service