Status: November 2026. The history part is stable; items marked "contested" or "general knowledge" are explained in the text. The trends part is a snapshot of plans and announcements, which can change; roadmap dates for 6G, post-quantum security and switch-offs are targets, not guarantees.
1. A timeline you can remember
| Year | Event | Why it matters |
|---|---|---|
| 1876 | Telephone patent (Bell) (general knowledge) | Start of voice over wires |
| 1973 | First handheld mobile phone call (Martin Cooper, Motorola) (general knowledge) | Mobile telephony becomes imaginable |
| ~1979–1983 | First analogue 1G systems (Japan, Nordic NMT, US AMPS) (general knowledge; not re-checked) | Voice only, no encryption, national systems |
| 27 March 1991 | First successful GSM test call (Nokia) | GSM reaches prototype stage |
| 1 July 1991 | Official first commercial GSM call: Finland's prime minister Harri Holkeri called Tampere's deputy mayor over Radiolinja's network | Birth of 2G. Priority is contested (Ericsson notes its systems placed GSM calls in several cities that day; a former Nokia engineer later claimed a test call a few hours earlier) |
| 3 Dec 1992 | First SMS: "Merry Christmas", sent by Neil Papworth from a PC to Vodafone director Richard Jarvis, who received it on an Orbitel 901 | Text messaging (based on the account of Papworth and Vodafone UK) |
| 2001 | First commercial 3G: NTT DoCoMo FOMA, launched on 1 October 2001 (delayed from 30 May because of W-CDMA technical problems) | Mobile data starts; early FOMA was not compatible with standard UMTS until upgrades in 2004 |
| 2007 | iPhone (general knowledge) | Smartphone era; data overtakes voice |
| Dec 2009 | First commercial LTE by TeliaSonera in Stockholm (Ericsson) and Oslo (Huawei) | All-IP 4G ("4G" naming was disputed because of speed definitions) |
| Aug 2012 | First commercial VoLTE (SK Telecom, LG U+, MetroPCS) | Voice becomes a packet service |
| 2017 | EU "roam like at home" starts | End of most EU roaming surcharges |
| 2018–2019 | First commercial 5G (fixed-wireless in the US, Korea, then phones) | New radio, new core, slicing |
| 2020 | First 5G in Croatia (DSS, October); EU 5G toolbox | Security and supply chain become policy |
| 2022 | EU roaming extended to 2032 | Regulatory continuity |
| 2024 | Australia switches off 3G (TPG Jan; Telstra and Optus 28 Oct) | 3G sunset era begins in earnest |
| 2025 | Vodafone + Three merge (UK, 31 May); EchoStar sells spectrum (US); XLSmart merger (Indonesia); SK Telecom HSS breach (Korea); Ofcom bans GT leasing | Consolidation and security |
| 2025–26 | Serbia (Dec 2025) and Turkey (Apr 2026) launch 5G; fibre overtakes copper in Croatia (Q1 2026); France plans to merge SFR into the other three (Jun 2026) | The map keeps changing |
2. Five big shifts in 150 years
- Circuits → packets. Voice was a reserved line; now it is IP packets (VoLTE, VoNR); even SMS is moving to IMS.
- Voice → data. 2G sold minutes; 4G/5G sell gigabytes. SMS is falling (Croatia: −21.8% year on year in Q1 2026) while data traffic grows.
- Hardware → software. Dedicated boxes (MSC, HLR) became virtual and cloud-native functions (AMF, UDM) on standard servers.
- Closed → open interfaces. Open RAN, open APIs (CAMARA), SBA with HTTP/2, open-source cores.
- Telecom → critical infrastructure. Regulation (NIS2, 5G toolbox, GT-leasing bans) and security incidents moved telecom into the centre of national resilience.
3. Trends — where things stand (late 2026)
3.1 Switching off 2G and 3G
- The GSA counted 313 completed, planned or ongoing 2G/3G switch-offs in 89 countries and territories by 30 June 2026; Europe accounts for 43%.
- Germany: Deutsche Telekom has planned to switch off 2G on 30 June 2028 (other reports differ).
- UK: all operators have committed to shutting down 2G and 3G by 2033; EE plans to begin 2G shutdown in May 2029, O2 in summer 2029, Vodafone during 2030.
- Switzerland: 3G phase-out planned for the end of 2026.
- Croatia: no source found in this research — check HAKOM and the operators.
- What goes wrong in a shutdown: old phones, M2M devices (alarms, meters, cars), emergency calls and roamers (Module 32, Australia).
3.2 5G standalone and 5G-Advanced
- Europe is behind on 5G SA (about 2% of 5G users, versus about 24% in the US and 77% in China as reported in 2025, Module 31).
- 5G-Advanced (3GPP Releases 18 onward) adds AI/ML in RAN, better uplink, RedCap and satellite (Module 12).
3.3 6G — a roadmap, not a product
- 3GPP Release 20 carries the 6G studies (reported as completing around mid-2027).
- Release 21 is expected to produce the first normative 6G specifications; reports give different freeze dates (late 2028 to 2029).
- ITU IMT-2030 process: technology proposals around early 2029; commercial availability targeted around 2030 (a target; many analysts expect 2029–early 2030s).
- Likely themes (research directions, not guarantees): sub-THz and new mid-bands, integrated sensing and communication (ISAC), AI-native networks, satellite integration, energy efficiency.
3.4 Network APIs and "programmable networks"
- GSMA Open Gateway / CAMARA: common APIs to let developers use network capabilities. GSMA reports 86 operators and over 300 networks adopting them (March 2026, self-reported).
- The most common are SIM Swap and Number Verification (anti-fraud, Module 29). GSMA says it is close to protecting about two-thirds of mobile connections with them (self-reported); launches reported in Italy, Qatar, Colombia, Uruguay, Greece, Poland, Australia and others.
- Route to market: aggregators and cloud/API marketplaces.
3.5 Messaging: from SMS to RCS and encrypted chat
- RCS Universal Profile 3.0 (March 2025) adds end-to-end encryption using IETF Messaging Layer Security (MLS). Apple and Google both announced support, with a beta rollout reported on supported carriers (iOS 26.5; Apple's announcement date was reported as 11 May — year not confirmed).
- Impact: SMS-based OTP stays, but business messaging and fraud shift to RCS and app channels; sender verification matters (Modules 5, 27).
3.6 Post-quantum security
- A future quantum computer could break today's public-key cryptography, so "harvest now, decrypt later" is a concern for long-lived data and SIMs.
- GSMA Post-Quantum Telco Network Task Force (since 2022): impact-assessment paper PQ.01 (Feb 2023), risk-management guidelines (Sept 2023), satellite paper PQ.07 (Feb 2026).
- 3GPP is still studying PQC for network specifications; the proposed industry target mentioned at a 2026 ITU workshop is completion between 2030 and 2035 (a proposal, not a commitment).
- Practical steps: crypto inventory, hybrid algorithms in TLS/IPsec, quantum-ready SIM/eSIM for new issuance.
3.7 Satellite and non-terrestrial networks
Direct-to-device and NTN in 3GPP (Module 17) move from trials to services; spectrum, interference and roaming rules are the open questions.
3.8 AI in networks
AI for network optimisation, fault prediction, energy saving and fraud detection (SON, closed-loop automation), and "AI-RAN" (RAN compute shared with AI workloads). Treat vendor claims carefully; evidence is mixed and evolving (general trend; not tied to a single source here).
3.9 Market structure and money
- Consolidation 4→3 (US, UK, Indonesia; France and Italy in play), tower spin-offs, network sharing (Modules 30–32).
- SMS revenue shrinks; A2P is fragile; operators look to API monetisation, FWA, private networks and fibre.
- Fibre replaces copper (Croatia 2026) and fixed-mobile convergence grows.
3.10 Security and regulation
NIS2, 5G Toolbox, GT-leasing bans, SS7/Diameter firewall mandates, post-incident fines (SK Telecom, Optus) and sovereignty rules (vendor restrictions). Expect more regulation of incidents and supply chains, not less.
4. What to learn next (a path for a telecom professional)
- Stay literate in basics: identities, call/SMS flows, 4G/5G cores (Modules 0–12, 28).
- Pick one depth: radio (20), core and signalling (3–4, 23, 25), security (15, 25–27), regulation (22), business (29–32).
- Practise with traces and labs (Module 23) and open-source cores.
- Follow a few primary sources: 3GPP release news, GSMA reports, your regulator's quarterly data, vendor/analyst reports (Dell'Oro, Omdia), and trade press (TelecomTV, RCR Wireless, TeleGeography).
- Keep a "facts with dates" notebook — in telecom, every number has an expiry date.
5. Quick forecasting rules of thumb
- Standards move slowly (a generation every ~10 years), markets move faster (mergers within a year), security incidents are unpredictable but recur.
- Old networks last longer than planned because of IoT, roaming and emergency calls.
- Whatever is announced as "2030" in telecom usually means "late 2020s to mid-2030s".
Remember this: telecom history is a story of replacing the layer under the service while keeping the service — a call is still a call, a text is still a text — and of every layer, from copper to the cloud, being pulled into one software-defined, regulated and security-critical system.