Manages radio transmissions over the air interface (Um interface) using a combination of FDMA and TDMA .
Used by network operators to monitor and control the overall system, including performance and maintenance tasks. Protocol Stack
Uses the Subscriber Identity Module (SIM) to store unique identity information. Security is maintained through a challenge-response authentication mechanism and over-the-air encryption using algorithms like A5. GSM – Architecture, Protocols and Services
Support for data transmission, originally limited to 9.6 kbps but later improved through upgrades like GPRS and EDGE .
A temporary database storing information for subscribers currently roaming in its area. Manages radio transmissions over the air interface (Um
The Global System for Mobile Communications (GSM) is the foundational standard for second-generation (2G) digital cellular networks. It was developed to provide a unified digital mobile system that facilitates seamless international roaming and secure voice and data services.
Uses modified versions of LAPD (called LAP-Dm) for the air interface and SS7 protocols (MTP) for the network interface. Layer 3 (Network): Divided into three sublayers: The Global System for Mobile Communications (GSM) is
GSM provides a variety of standard services and built-in security measures: