On June 1, 1991, the first commercial calls over GSM were made in Finland and Sweden, Nokia Siemens and Ericsson noted Friday as they celebrated the anniversary by recollecting the early days of the technology.
In Finland, former prime minister Harri Holkeri called Kaarina Suonio, vice mayor of the city of Tampere, from Helsinki and spoke about how good the new technology was: "it is like speaking to a neighbor," Holkeri said.
On the other side of the Gulf of Bothnia a more low-key event took place. Late in the afternoon, Ericsson's Jan Wäreby -- who still works at the company and heads up sales and marketing -- and Yngve Zetterström, Televerket's (now TeliaSonera) GSM project manager called Tony Hagström, general director at Televerket, Wäreby recalls in the book Changing the World.
In Copenhagen, Ericsson also demonstrated GSM for the Danish telecom authority.
Like today, competition between vendors was cutthroat.
However, one thing all involved in the early days of GSM agree on is that they, back then, couldn't imagine the immense popularity the technology would eventually enjoy.
They knew GSM would be big, but not as big as it is today, according to Wäreby. Few even dared to dream about the future, Timo Ali-Vehmas, vice president of compatibility and industry collaboration Nokia, said.
Twenty years later, the technology covers 80 percent of the world's population, according to the GSM Association. Today's 838 GSM networks in 234 countries and independent territories around have more than 4.4 billion subscriptions, and another million subscriptions are added every day, according to industry organization Global mobile Suppliers Association.
Base stations and mobile phones have evolved enormously since the beginning of the nineties. The Nokia 1011, which arrived in 1992, weighed 475 grams, almost 4 times as much as the Samsung Galaxy S II, which comes in at 116 grams.
On the network side, base stations have increased their scalability from about 600 voice subscribers per site to 60,000 voice subscribers, according to Ericsson.
However, one thing that heavy users of today's smartphones can relate to was the need to constantly charge their phone. Though battery life is longer now, frequent mobile phone callers still must charge their devices every day.
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