This year 2021 is fulfilled three decades since the launch of the world’s first commercial SIM card, created by the German security technology group Giesecke + Dvrient (G + D), which handed it over to a Finnish telecommunications company to start selling it.
Despite being 1991 the year in which this type of cards began to be used, the technologies that support it were developed several years before their arrival on the market. The G + D company registered the first patent in 1968.
Later, in 1989, these insertable and interchangeable SIM cards were defined and standardized and, In 1990, a milestone occurred with the introduction of the SIM Toolkit standard. This allowed to extend the functions between the card and a GSM phone (acronym for Global System Mobile).
The SIM is made up of a microprocessor and an operating system that provide secure access to the mobile network. Although it is true that, at first, its size was like that of a credit card, over time it has undergone a process of transformation of its dimensions: from mini to nano SIM.
In order to use these chips, GSM networks are necessary and these, in turn, require a way to identify users through their phone number and device in order to make and receive calls.
In this way, SIM cards include the local area identification number and your key, as well as operator data necessary to be able to be in contact with other users, either by voice calls or by short messages (SMS).
Furthermore, they have the ability to gsave these messages and the device’s contact book, so that when switching to another mobile, it is possible to recover all the phones that have been recorded on it.
Over time, SIM cards have been transformed, adapting to the devices that host them and becoming smaller and smaller. Depending on the age of the phone, we can find them in different sizes.
The original SIMs, similar in size to a credit card, are no longer used. They were big (85.6 x 55.98 millimeters) and had little capacity to store contacts or messages. Its successor was the miniSIM, which is now known as SIM.
Its standard format was 25×15 millimeters and it fit in all devices. However, in 2003 an even smaller card, microSIM, 15×12 millimeters, was developed. Much of its plastic cover was removed, leaving only the chip.
The last to reach the most smartphones was the nanoSIM, of an even smaller size (12.3 x 8.8 millimeters). It was in 2012 when it was implemented in almost all phones and with it manufacturers could optimize the space of the hardware of the devices. With this evolution, their ability to store information also grew.
Currently, most technology manufacturers choose to create phones with MultiSIM option, that is, they offer the possibility that users can use a single terminal with several of these cards, which translates into different telephone numbers that coexist in a device.
ESIM, the most up-to-date cards
The introduction of eSIM (or embedded SIM) technology in 2012 was another milestone in the field of technology since, from then on, the download of the SIM profile on the device was allowed. This opened a new range of possibilities for digitization and logistics optimization.
To do this, a generic SIM module as a permanent chip called eUICC (Universal Integrated Circuit Card) is installed in the device. Its customization is done remotely by providing, via mobile communications or a local area network (WLAN), data from network operators.
Because of this, is increasingly common for manufacturers of smartphones, tablets or smart watches present more frequently a kit that has eSIM technology. In parallel, eSIM technology continues to evolve in the field of iUICCs, better known as embedded SIMs.
These are a tamper-proof element (TRE) inside a SoC (system on a chip), so that the SIM is no longer an insertable ‘hardware’ module as it was before, but forms a single connectivity module.