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2G facts for kids

Kids Encyclopedia Facts

2G is a short notation for second-generation cellular network, a group of technology standards employed for cellular networks. 2G was commercially launched on the GSM standard in Finland by Radiolinja (now part of Elisa Oyj) in 1991. After 2G was launched, the previous mobile wireless network systems were retroactively dubbed 1G. While radio signals on 1G networks are analog, radio signals on 2G networks are digital, though both systems use digital signaling to connect cellular radio towers to the rest of the mobile network system. 2G was superseded by 3G technology.

The most common 2G technology was the time-division multiple access (TDMA)-based GSM standard, used in most of the world outside Japan. In North America, Digital AMPS (IS-54 and IS-136) and cdmaOne (IS-95) were dominant, but GSM was also used. In Japan the ubiquitous system was Personal Digital Cellular (PDC), though another, Personal Handy-phone System (PHS), also existed.

Three primary benefits of 2G networks over their 1G predecessors were:

  1. Digitally encrypted phone conversations, at least between the mobile phone and the cellular base station but not necessarily in the rest of the network.
  2. Significantly more efficient use of the radio frequency spectrum enabling more users per frequency band.
  3. Data services for mobile, starting with SMS text messages then expanding to Multimedia Messaging Service (MMS).

With General Packet Radio Service (GPRS), 2G offers a theoretical maximum transfer speed of 40 kbit/s (5 kB/s). With EDGE (Enhanced Data Rates for GSM Evolution), there is a theoretical maximum transfer speed of 384 kbit/s (48 kB/s).

Evolution

Cellular network standards and generation timeline
Cellular network standards and generation timeline. (Large titles on the colored area refer to the lines to their right.

2.5G (GPRS)

2.5G ("second-and-a-half generation") is used to describe 2G-systems that have implemented a packet-switched domain in addition to the circuit-switched domain. It does not necessarily provide faster service because bundling of timeslots is used for circuit-switched data services (HSCSD) as well.

2.75G (EDGE)

GPRS networks evolved to EDGE networks with the introduction of 8PSK encoding. While the symbol rate remained the same at 270.833 samples per second, each symbol carried three bits instead of one. Enhanced Data rates for GSM Evolution (EDGE), Enhanced GPRS (EGPRS), or IMT Single Carrier (IMT-SC) is a backward-compatible digital mobile phone technology that allows improved data transmission rates, as an extension on top of standard GSM. EDGE was deployed on GSM networks beginning in 2003, initially by AT&T in the United States.

Phase-out

2G, understood as GSM and CdmaOne, has been superseded by newer technologies such as 3G (UMTS / CDMA2000), 4G (LTE / WiMAX) and 5G (5G NR). However, 2G networks were still available as of 2023 in most parts of the world, while notably excluding the majority of carriers in North America, East Asia, and Australasia.

Many modern LTE-enabled devices have the ability to fall back to 2G for phone calls, necessary especially in rural areas where later generations have not yet been implemented. In some places, its successor 3G is being shut down rather than 2G – Vodafone previously announced that it had switched off 3G across Europe in 2020 but still retains 2G as a fallback service. In the US T-Mobile shut down their 3G services while retaining their 2G GSM network.

Various carriers have made announcements that 2G technology in the United States, Japan, Australia, and other countries are in the process of being shut down, or have already shut down 2G services so that carriers can re-use the frequencies for newer technologies (e.g. 4G, 5G).

In 2022, Android 12 introduced a system setting to disable 2G connectivity for the device, as 2G is considered to be insecure. Specifically, there exist well known methods to attack weaknesses in GSM since 2009 with practical use in crime. Attack routes on 2G CdmaOne were found later and remain less publicized.

Past 2G networks

Country Network Shutdown date Standard Notes
 Åland Ålcom 2024 GSM 2G availability cannot be guaranteed after 1 Jan 2022, all stations are planned to be shut down in 2024.
 Australia Optus 2017-08-01 GSM 2G shut down in WA and NT on 03 Apr 2017.
Telstra 2016-12-01 GSM
Vodafone 2018-06-30 GSM
 Bahrain Batelco 2021-11-30 GSM
 Belgium Orange 2030 GSM
Telenet 2027 GSM
Proximus 2027 GSM
 Brunei DSTCom 2021-06-01 GSM
Progresif 2021-06-01 GSM
imagine 2021-06-01 GSM
 Canada Bell 2019-04-30 cdmaOne Shutdown of CDMA transmitters commenced in remote areas in 2017, followed by an official announcement in June 2018 that 2G devices will lose service soon.
Rogers Wireless GSM 1900 MHz shutdown in Jun 2021.
850 MHz remains active.
SaskTel 2017-07-31 cdmaOne
Telus Mobility 2017-05-31 cdmaOne
 Cayman Islands Digicel 2020-07-01 GSM
 China China Unicom GSM Local shutdown commenced in Q1 2021.
China Telecom 2025 cdmaOne Local shutdown commenced on 16 Jun 2020.
CDMA2000 1xRTT, EV-DO Rev. A/B (3G) service also terminates.
 Colombia Claro 2023-02-23 GSM
Tigo 2022-11-01 GSM
 France Bouygues 2026-12-31 GSM
Orange 2025-12-31 GSM
SFR 2026 GSM
 Hong Kong 3 2021-09-30 GSM
SmarTone 2022-10-14 GSM
 Iceland 2025 GSM per government statement
 Israel 2025 GSM per government statement
 Jamaica FLOW 2024-04-15 GSM
Shutdown commenced on 30 Sep 2022.
Digicel 2024-08-31 GSM
 Japan au KDDI 2008-03-31 cdmaOne
NTT Docomo 2012-03-31 PDC
Softbank 2010-03-31 PDC
 Jordan Umniah 2022-??-?? GSM
 Luxembourg Orange 2030 GSM
 Macau China Telecom 2010-??-?? cdmaOne
CTM 2019-08-01 GSM Service for local customers terminated on 04 Jun 2015 with service remaining for roaming users.
3 2019-08-01 GSM Service for local customers terminated on 04 Jun 2015 with service remaining for roaming users.
SmarTone 2019-08-01 GSM Service for local customers terminated on 04 Jun 2015 with service remaining for roaming users.
 Mexico AT&T GSM Local shutdown commenced in Q1 2019.
Movistar 2021-01-01 GSM
 Netherlands T-Mobile 2021-06-01 /
2023-11-15 (IoT)
GSM
 New Caledonia OPT-NC 2025 GSM Shutdown commenced in 2022.
 New Zealand 2degrees 2018-03-15 GSM
Spark 2012-07-31 cdmaOne
 Norway Telenor 2025 GSM
Telia 2025 GSM
 Poland Orange 2030 GSM
 Romania Orange 2030 GSM
 Saint Vincent and the Grenadines FLOW 2023-09-30 GSM
 Singapore M1 2017-04-18 GSM
Singtel 2017-04-18 GSM
StarHub 2017-04-18 GSM
 Sint Maarten TelCell 2019-01-01 GSM
UTS 2017-09-26 GSM
 Slovakia Orange 2030 GSM
 South Africa 2024-06-30 GSM per government statement
 South Korea KT 2012-03-19 cdmaOne CDMA2000 1xRTT, EV-DO Rel. 0 (3G) service has also terminated.
LG Uplus 2021-06-30 cdmaOne CDMA2000 1xRTT, EV-DO Rev. A/B (3G) service has also terminated.
SK Telecom 2020-07-27 cdmaOne CDMA2000 1xRTT, EV-DO Rel. 0 (3G) service has also terminated.
 Spain Orange 2030 GSM
 Switzerland Salt 2020-12-31 GSM
Shutdown commenced on 01 Jul 2020. A few single 2G-only sites remained until Sep 2023 to preserve CSFB functionality.
Sunrise 2023-01-03 GSM
With the introduction of S-RAN in 2018 phaseout was postponed to 2022.
Swisscom 2021-04-07 GSM
Official shutdown date was on 31 Dec 2020 (guaranteed availability).
 Taiwan Chunghwa Telecom 2017-06-30 GSM
FarEasTone 2017-06-30 GSM
Taiwan Mobile 2017-06-30 GSM
 Trinidad and Tobago Digicel 2024-12-31 GSM
 United Arab Emirates Du 2023-12-31 GSM
Etisalat 2023-12-31 GSM
 United Kingdom 2033 GSM per government statement on confirmation by mobile providers
 United States
 Puerto Rico
 US Virgin Islands
AT&T 2017-01-01 GSM
Cellcom 2023-12-01 cdmaOne CDMA2000 1xRTT, EV-DO Rev. A (3G) service has also terminated.
Commnet Wireless (Choice) 2022-12-31 cdmaOne CDMA2000 1xRTT, EV-DO Rev. A (3G) service has also terminated.
Copper Valley Wireless 2022-09-30 cdmaOne CDMA2000 1xRTT, EV-DO Rev. A (3G) service has also terminated.
T-Mobile TBD GSM
T-Mobile (Sprint) 2022-05-31 cdmaOne CDMA2000 1xRTT, EV-DO Rev. A (3G) service has also terminated.
Shutdown commenced on 31 Mar 2022.
Union Wireless 2015 GSM
UScellular 2024-01-14 cdmaOne CDMA2000 1xRTT, EV-DO Rev. A (3G) service will also terminate.
Verizon 2022-12-31 cdmaOne CDMA2000 1xRTT, EV-DO Rev. A (3G) service also terminated.
 Venezuela Digitel 2025 GSM Shutdown commenced in May 2021.
Movilnet 2025 GSM
Movistar 2025 GSM Shutdown commenced on 01 July 2022.
 Vietnam GSM per government statement
Shutdown commenced in Dec 2023.
2024-09 (for 2G-only devices)
2026-09 (for 3G and 4G (without VoLTE) devices)

See also

Kids robot.svg In Spanish: Telefonía móvil 2G para niños

  • Cliff effect
  • Dropout
  • List of mobile phone generations
  • Mobile radio telephone, also known as 0G
  • 1G
  • 3G
  • 4G
  • 5G
  • Wireless device radiation and health
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