2G

2G (or 2-G) is short for second-generation cellular network. 2G cellular networks were commercially launched on the GSM standard in Finland by Radiolinja (now part of Elisa Oyj) in 1991.[1]

For other uses, see 2G (disambiguation).

Three primary benefits of 2G networks over their 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.

2G technologies enabled the various networks to provide the services such as text messages, picture messages, and MMS (multimedia messages).

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. Both systems use digital signaling to connect the radio towers (which listen to the devices) to the rest of the mobile system.

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

The most common 2G technology was the time division multiple access (TDMA)-based GSM, originally from Europe but used in most of the world outside Japan and North America. In North America, Digital AMPS (IS-54 and IS-136) and cdmaOne (IS-95) were the main systems. In Japan, the ubiquitously deployed system was Personal Digital Cellular (PDC).

Evolution

2.5G (GPRS)

See also: General Packet Radio Service

2.5G ("second and a half generation"[3]) is used to describe 2G-systems that have implemented a packet-switched domain in addition to the circuit-switched domain. It doesn't necessarily provide faster service because bundling of timeslots is used for circuit-switched data services (HSCSD) as well.

2.75G (EDGE)

See also: Enhanced Data Rates for GSM Evolution

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.

Past 2G networks

2G, understood as GSM and CDMA, has been superseded by newer technologies such as 3G (UMTS / CDMA2000), 4G (LTE) and 5G; however, 2G networks are still used in most parts of Europe, Africa, Central America and South America.[4][5][6] Various carriers have made announcements that 2G technology in the United States, Japan, Australia, and other countries is in the process of being shut down, or have already shut down 2G services so that carriers can reclaim those radio bands and re-purpose them for newer technologies (e.g. 4G LTE).[7][8]

Country	Network	Total decommission date	Details
Australia	Optus	2017	Optus shut down 2G in Western Australia and Northern Territory on 3 April 2017 and completed the shutdown within the rest of Australia on 1 August 2017.[9]
	Telstra	2016	Telstra closed their GSM network on 1 December 2016, being the first mobile provider in Australia to switch off 2G.[10]
	Vodafone	2018	Vodafone closed their legacy GSM network on 30 June 2018.[11]
India	Airtel	No plan to shut down 2G.	Bharti Airtel, the largest carrier in India, will shut down their 3G network in mid-2020, while they have no plans to shut down 2G services.[12]
	Reliance	2017	Reliance Communications, a group led by Reliance ADAG, decided to shut down their entire 2G network at the end of November 2017. It is the first operator in the country to do so.[13]
Japan	au KDDI	22 July 2012	Qualcomm cdmaOne standard[14]
	NTT Docomo	31 March 2012	PDC standard, not compatible with GSM[15]
	Softbank	31 March 2010
South Korea	KT	19 March 2012	[16]
	LG Uplus	30 June 2021 (TBC)
	SK Telecom	27 July 2020	[17]
Mexico	AT&T Mexico	2020	AT&T Mexico has started the shutdown of their 2G network on the country.[18]
	Movistar		Movistar Mexico started the shutdown of their 2G network in April 2019.[19]
Netherlands	T-Mobile	15 November 2020 (TBC)	T-Mobile Netherlands will shut down 2G services by 15 November 2020.[20][21]
New Zealand	2degrees	2018	2degrees shutdown their 2G network on 15 March 2018.[22]
	Spark (CDMA)	2012	Spark's 2G network (CDMA) was shut down on 31 July 2012. Spark now operates 3G and 4G networks, and was the first mobile provider in New Zealand to switch off 2G.[23]
	Warehouse Mobile	2018	Warehouse Mobile, partnered with 2degrees, shut their 2G network down in March 2018, to make way for the new 4G network.[24]
Singapore	M1	1 April 2017	[25]
	Singtel
	StarHub
Switzerland	Sunrise	2024	Sunrise Communications AG has originally announced plans to phase out their GSM network by the end of 2018, but decided to postpone the phase out to 2024 [26].
	Swisscom	2021	Telecommunications in Switzerland is mainly operated by state-owned Swisscom, and the two privately held Salt and Sunrise Communications AG as these companies have a license to operate 2G. Swisscom will cease 2G services due to their "public service requirements" only by 1 January 2021.[27]
Taiwan	Chunghwa Telecom	30 June 2017	[28]
	FarEasTone
	Taiwan Mobile
Thailand	AIS	31 October 2019	Thailand's National Broadcasting and Telecommunications Commission (NBTC) has approved 31 October 2019 as the date for shutdown of Thailand's 2G mobile network. According to the NBTC, the shutdown will increase efficiency for network operators and open the door for 5G wireless broadband service by 2020. Operators are expected to migrate their 2G users to 3G and 4G services. Provincial governments will assist in informing 2G users of the move. The NBTC will cease their use of 2G standards and inform handset retailers and importers of the network's impending closure.[29]
	DTAC
	TrueMove H
United States	AT&T	2017	AT&T's 2G GSM service was shut down in January 2017.[30][31][32] This shutdown had a notable impact on the electronic security industry, where many 2G GSM radios were in use for alarm signal communication to central station dispatch centers. 2G GSM radios were required to be replaced by newer generation radios to avoid service outages.[33]
	T-Mobile	2020 (TBC)	T-Mobile US has postponed shutdown of their 2G network until 2020.[34]
	Verizon	31 December 2020	Verizon plans to shut down their 2G and 3G CDMA-based network by 31 December 2020.[35][36]
	Sprint	31 December 2021	Sprint plans to shut down their 2G CDMA-based network by 31 December 2021.[37]

See also

• Cliff effect
• Dropout
• List of mobile phone generations
• Mobile radio telephone, also known as 0G
• 3G
• 4G
• 5G

References

1. "Radiolinja's History". 20 April 2004. Archived from the original on 23 October 2006. Retrieved 23 December 2009.
2. "GPRS & EDGE". 3gpp.org. Retrieved 17 August 2019.
3. "What is Second and a Half Generation (2.5G) | IGI Global". www.igi-global.com. Retrieved 6 October 2019.
4. "Germany's rural 4G users still spend one-fourth of their time on 3G and 2G networks". Opensignal. 13 June 2019. Retrieved 6 October 2019.
5. "T-Mobile Poland expects to keep 2G for five-to-six years". TeleGeography A. Division of PriMetrica. 17 July 2019. Retrieved 6 October 2019.
6. "2G phase-out – modernisation of the Swisscom mobile network | Swisscom". www.swisscom.ch. Retrieved 6 October 2019.
7. Serr, Melanie (5 April 2017). "What You Need To Know About the 2G Network Shutdown". Geotab Blog. Retrieved 6 October 2019.
8. "The status of the 2G/3G network sunset". nae_ global. 31 July 2019. Retrieved 11 December 2019.
9. "2G Network Closure Update" (Press release). Optus. Retrieved 6 July 2017.
10. Turner, Adam (4 November 2016). "Budget Mobile Customers Brace for Australia's 2G Shutdown". Sydney Morning Herald. Retrieved 26 December 2016.
11. "We've switched off our 2G network". Vodafone Australia. Archived from the original on 5 April 2018.
12. "Airtel to kill off its 3G networks in India by the middle of next year". Totaltelecom. Retrieved 9 October 2019.
13. "RComm to Shut Down 2G Network in a Month, Will Continue with 4G Only Network Like JIO".
14. "「CDMA 1X」などのサービス終了等のお知らせ〈別紙〉 | 2011年 | KDDI株式会社". kddi.com. Retrieved 15 July 2019.
15. "Press Releases | News & Notices | NTT DOCOMO". nttdocomo.co.jp. Retrieved 15 July 2019.
16. "A Complete Overview of 2G & 3G Sunsets".
17. "SK Telecom starts to terminate 2G services".
18. "Most used 2G mobile phones in India". Comparetrap.
19. Escalona, Claudia Juárez. "Movistar y AT&T ponen en marcha apagón 2G". El Economista. Retrieved 26 March 2019.
20. "T-Mobile NL prepares customers for eventual GSM shutdown". Telecompaper. 5 January 2017. Retrieved 23 July 2020.
21. "T-Mobile Netherlands GSM shutdown 15 november 2020".
22. "2degrees to close down 2G access in March 2018". 2degrees. Retrieved 26 September 2017.
23. "Telecom closes CDMA network". The New Zealand Herald. Retrieved 1 August 2012.
24. "Coverage". Warehouse Mobile. 12 November 2015. Retrieved 5 May 2019.
25. "2G Services to Cease on 1 April 2017". Retrieved 20 July 2020.
26. "5G kommt – 2G wird abgeschaltet. Was sind die Folgen?". Retrieved 20 July 2020.
27. "Swisscom is equipping its mobile network for the future". Retrieved 2 November 2015.
28. "Taiwan's NCC urges 2G users to upgrade by June". telecomasia.net. Retrieved 15 April 2019.
29. "Thailand to Close 2G Network".
30. Gryta, Thomas (3 August 2012). "AT&T to Leave 2G Behind". The Wall Street Journal. Retrieved 26 December 2016.
31. "AT&T 2G Sunset". povertymobile. 20 January 2016. Retrieved 11 January 2017.
32. "AT&T's Donovan Says 2G Network in 'Soft Lock', Decommissioning to Begin in Coming Months". FierceWireless.com. Retrieved 11 January 2017.
33. "2G Sunset Overview". Telguard. 21 July 2011. Archived from the original on 21 February 2015. Retrieved 26 December 2016.
34. Abent, Eric (14 September 2016). "T-Mobile Takes a Swing at AT&T, Says Its 2G Network Will Stay Active through 2020". SlashGear. Retrieved 26 December 2016.
35. "CDMA Network Retirement". Verizon Wireless. Retrieved 12 January 2020.
36. Dampier, Phillip (1 August 2019). "Verizon Delays Shutdown of 3G CDMA Network Until the End of 2020". Stop the Cap!. Retrieved 12 January 2020.
37. "2G, 3G, 4G LTE Network Shutdown Updates". digi.com. Retrieved 20 July 2020.

Preceded by 1st Generation (1G)

Mobile Telephony Generations

Succeeded by 3rd Generation (3G)