# Learn 2G - GSM ## Learn 2G - GSM - [Intro](https://gsm.learn-telecom.com/intro.md): Dive into our comprehensive article discussing 2G - GSM technology, its history, impact and evolution. Explore how the 2G network revolutionized communication. - [Standards](https://gsm.learn-telecom.com/standards.md) - [Timeline](https://gsm.learn-telecom.com/standards/timeline.md) - [PCM30](https://gsm.learn-telecom.com/standards/pcm30.md) - [PCM24](https://gsm.learn-telecom.com/standards/pcm24.md) - [GSM Radio Stack](https://gsm.learn-telecom.com/architecture/gsm-radio-stack.md) - [Layer 1 - Radio](https://gsm.learn-telecom.com/architecture/gsm-radio-stack/layer-1-radio.md) - [Layer 2 - LAP-Dm](https://gsm.learn-telecom.com/architecture/gsm-radio-stack/layer-2-lap-dm.md) - [Layer 3 − GSM signalling](https://gsm.learn-telecom.com/architecture/gsm-radio-stack/layer-3-gsm-signalling.md) - [MS - Mobile Station](https://gsm.learn-telecom.com/architecture/ms-mobile-station.md) - [ME - Mobile Equipment](https://gsm.learn-telecom.com/architecture/ms-mobile-station/me-mobile-equipment.md) - [Baseband](https://gsm.learn-telecom.com/architecture/ms-mobile-station/me-mobile-equipment/baseband.md) - [SIM Card - Subscriber Identity Module](https://gsm.learn-telecom.com/architecture/ms-mobile-station/sim-card-subscriber-identity-module.md) - [BSS - Base Station Subsystem](https://gsm.learn-telecom.com/architecture/bss-base-station-subsystem.md) - [BTS - Base Transceiver Station](https://gsm.learn-telecom.com/architecture/bss-base-station-subsystem/bts-base-transceiver-station.md) - [BSC - Base Station Controller](https://gsm.learn-telecom.com/architecture/bss-base-station-subsystem/bsc-base-station-controller.md) - [NSS - Network Switching Subsystem](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem.md) - [MSC - Mobile Switching Center](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem/msc-mobile-switching-center.md) - [HLR - Home Location Register](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem/hlr-home-location-register.md) - [VLR - Visitor Location Register](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem/vlr-visitor-location-register.md) - [AuC - Authentication Center](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem/auc-authentication-center.md) - [EIR - Equipment Identity Register](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem/eir-equipment-identity-register.md) - [VMS - Voice Mail Subsystem](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem/vms-voice-mail-subsystem.md) - [IWF - Interworking Function](https://gsm.learn-telecom.com/architecture/nss-network-switching-subsystem/iwf-interworking-function.md) - [OSS - Operation Support Subsystem](https://gsm.learn-telecom.com/architecture/oss-operation-support-subsystem.md) - [OMC - Operation and Maintence Center](https://gsm.learn-telecom.com/architecture/oss-operation-support-subsystem/omc-operation-and-maintence-center.md) - [NMC - Network Managment Center](https://gsm.learn-telecom.com/architecture/oss-operation-support-subsystem/nmc-network-managment-center.md) - [ABC - Administration & Billing Center](https://gsm.learn-telecom.com/architecture/abc-administration-and-billing-center.md) - [Intro](https://gsm.learn-telecom.com/gsm-channels/intro.md) - [Traffic Channels](https://gsm.learn-telecom.com/gsm-channels/traffic-channels.md) - [TCH/F](https://gsm.learn-telecom.com/gsm-channels/traffic-channels/tch-f.md) - [TCH/H](https://gsm.learn-telecom.com/gsm-channels/traffic-channels/tch-h.md) - [Signalling Channels](https://gsm.learn-telecom.com/gsm-channels/signalling-channels.md) - [Broadcast Channels](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/broadcast-channels.md) - [FCCH - Frequency Correction Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/broadcast-channels/fcch-frequency-correction-channel.md) - [SCH - Synchronization Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/broadcast-channels/sch-synchronization-channel.md) - [BCCH - Broadcast Control Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/broadcast-channels/bcch-broadcast-control-channel.md): The broadcast control channel broadcasts general information on a base transceiver station per base transceiver station basis. - [CBCH - Cell Broadcast Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/broadcast-channels/cbch-cell-broadcast-channel.md) - [Common Control Channels](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/common-control-channels.md) - [Point-to-Multipoint Channels](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/common-control-channels/point-to-multipoint-channels.md) - [PCH - Paging Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/common-control-channels/point-to-multipoint-channels/pch-paging-channel.md) - [RACH - Random Access Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/common-control-channels/point-to-multipoint-channels/rach-random-access-channel.md) - [AGCH - Access Grant Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/common-control-channels/point-to-multipoint-channels/agch-access-grant-channel.md) - [Dedicated Channels](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/dedicated-channels.md) - [Point-To-Point Signalling](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/dedicated-channels/point-to-point-signalling.md) - [SDCCH - Stand-alone Dedicated Control Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/dedicated-channels/point-to-point-signalling/sdcch-stand-alone-dedicated-control-channel.md) - [SACCH - Slow Associated Control Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/dedicated-channels/point-to-point-signalling/sacch-slow-associated-control-channel.md): measurement reports to the network,power control and timing advance - [FACCH - Fast Associated Control Channel](https://gsm.learn-telecom.com/gsm-channels/signalling-channels/dedicated-channels/point-to-point-signalling/facch-fast-associated-control-channel.md) - [A interface](https://gsm.learn-telecom.com/gsm-interfaces/a-interface.md) - [A-ter interface](https://gsm.learn-telecom.com/gsm-interfaces/a-ter-interface.md) - [A-bis interface](https://gsm.learn-telecom.com/gsm-interfaces/a-bis-interface.md) - [Um interface](https://gsm.learn-telecom.com/gsm-interfaces/um-interface.md) - [Cell Id](https://gsm.learn-telecom.com/plmn-public-land-mobile-network/cell-id.md) - [LAI - Location Area Identification](https://gsm.learn-telecom.com/plmn-public-land-mobile-network/lai-location-area-identification.md) - [ARFCNs](https://gsm.learn-telecom.com/plmn-public-land-mobile-network/arfcns.md) - [System information-1(SI1)](https://gsm.learn-telecom.com/system-information-messages/system-information-1-si1.md): Cell ARFCN, RACH parameters required to access the system by MS and hopping related information are sent in this SI message. - [System information-2(SI2)](https://gsm.learn-telecom.com/system-information-messages/system-information-2-si2.md): Neighbour BCCH frequencies and PLMN information are sent in this SI. MS uses these frequencies for signal strength measurements required for handover. - [System information-2bis(SI-2bis)](https://gsm.learn-telecom.com/system-information-messages/system-information-2bis-si-2bis.md): RACH control and BCCH extension on neighbor cells - [System information-2ter(SI-2ter)](https://gsm.learn-telecom.com/system-information-messages/system-information-2ter-si-2ter.md): Information of BCCH extended allocated on which neighbor cells are provided in this SI. Broadcasted optionally on BCCH by the network to all the MSs. - [System information-2 Quarter (SI-2Quater)](https://gsm.learn-telecom.com/system-information-messages/system-information-2-quarter-si-2quater.md): 3G neighbor cell related information - [System information-3 (SI3)](https://gsm.learn-telecom.com/system-information-messages/system-information-3-si3.md): Carry following : 1. LAI of the current location area, 2. Cell identity, 3. Control channel information required to calculate paging group, 4. Cell options to achieve good performance in the cell, 5. - [System information-4 (SI4)](https://gsm.learn-telecom.com/system-information-messages/system-information-4-si4.md): CBCH and CBCH related frequency information, LAI, Cell selection parameters and RACH control information are carried by this SI4 message. - [System information-5 (SI5)](https://gsm.learn-telecom.com/system-information-messages/system-information-5-si5.md): It carries neighbor cell informations. In active mode, MS sends measurement reports in the uplink and output power/timing advance information in the downlink (on SACCH). Also gets BCCH carrier related - [System information-6 (SI6)](https://gsm.learn-telecom.com/system-information-messages/system-information-6-si6.md): Information on LAI, cell options, Cell identity and PLMN permitted or not is transmitted on this SI. - [System information-7 (SI7)](https://gsm.learn-telecom.com/system-information-messages/system-information-7-si7.md): Cell re-selection parameters needed by MS are sent on this SI. - [System information-8 (SI8)](https://gsm.learn-telecom.com/system-information-messages/system-information-8-si8.md): Cell re-selection parameters needed by MS are sent on this SI. - [System information-9 (SI9)](https://gsm.learn-telecom.com/system-information-messages/system-information-9-si9.md): Scheduling related some of the informations are sent on this SI. - [System information-13 (SI13)](https://gsm.learn-telecom.com/system-information-messages/system-information-13-si13.md): Carry GPRS related information needed for PS call. - [Page 2](https://gsm.learn-telecom.com/docs/page-2.md) - [Paging request type 1](https://gsm.learn-telecom.com/paging-requests/paging-request-type-1.md) - [Paging request type 2](https://gsm.learn-telecom.com/paging-requests/paging-request-type-2.md) - [Intro](https://gsm.learn-telecom.com/messages-for-mobility-management/intro.md): Table 9.38/GSM 04.08 summarizes the messages for mobility management - [Registration messages](https://gsm.learn-telecom.com/messages-for-mobility-management/registration-messages.md) - [IMSI DETACH INDICATION](https://gsm.learn-telecom.com/messages-for-mobility-management/registration-messages/imsi-detach-indication.md) - [LOCATION UPDATING ACCEPT](https://gsm.learn-telecom.com/messages-for-mobility-management/registration-messages/location-updating-accept.md) - [LOCATION UPDATING REJECT](https://gsm.learn-telecom.com/messages-for-mobility-management/registration-messages/location-updating-reject.md) - [LOCATION UPDATING REQUEST](https://gsm.learn-telecom.com/messages-for-mobility-management/registration-messages/location-updating-request.md) - [Security messages](https://gsm.learn-telecom.com/messages-for-mobility-management/security-messages.md) - [Connection management messages](https://gsm.learn-telecom.com/messages-for-mobility-management/connection-management-messages.md) - [Miscellaneous message](https://gsm.learn-telecom.com/messages-for-mobility-management/miscellaneous-message.md) --- # Agent Instructions This documentation is published with GitBook. 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