A Subscriber Identity Module (SIM) is a removable smart card for mobile phones. SIM cards store the required information to identify the mobile device. It also contains data required for voice encryption to make listening in on calls almost impossible (except when the wireless carrier itself is doing the eavesdropping).
In this way the customer ID (and personal number) is tied to the SIM card and not to a certain mobile phone. This allows for a seamless interchange of the same SIM card between different GSM mobile phones.
SIM cards also serve as storage for SMS messages and the user’s contacts. Current SIM cards can store up to 250 name/number pairs and up to 50 SMS text messages.
The SIM card cannot store multiple numbers per contact or other more complex information. This means that if you copy your contacts info from the phone memory to the SIM memory, contacts get broken up into as many entries as there are numbers for each individual contact and discards the other information.
All GSM phones and most iDEN phones require a SIM card to operate.
There are certain types of phones (CDMA, TDMA, AMPS) that do not use a SIM. Instead, the required data is programmed directly into the phone.
A new SIM on the market is an eSIM, the are none removable SIM’s that are integrated into devices that allows consumers to store multiple operator profiles on a device simultaneously, and switch between them remotely, though only one can be used at a time. The specification now extends to a wider range of devices, beyond the single companion device made possible with the first release.
The SIM cards come in four standard sizes:
- Full-size(85.6mm × 53.98mm × 0.76 mm)
- Mini-SIM(25mm x 15mm x 0.76mm)
- Micro-SIM(15mm x 12mm x 0.76mm)
- Nano-SIM(12.3mm × 8.8mm × 0.67mm)
The first to appear was the full-size or 1FF (1st Form Factor), the size of a credit card (85.60 mm × 53.98 mm × 0.76 mm). It was followed by a mini-SIM or 2FF (2nd Form Factor), which has the same thickness but is 25 mm long by 15 mm wide, with one of its corners cut to prevent misinsertion. Next came micro-SIM or 3FF (3rd Form Factor), with dimensions of 15 mm × 12 mm.
In 2012 the nano-SIM or 4FF (4th Form Factor) was introduced, which measures 12.3 × 8.8 × 0.67 mm. Nano-SIM cards can use adapters to gain compatibility with devices with Micro-SIM and Mini-SIM slots. A Micro-SIM card can also be fitted in Mini-SIM slot with an adapter.
STMicroelectronics Unveils Secure Cellular-Connectivity Offering for Industrial IoT and Automotive Applications
Geneva, February 6, 2020 – STMicroelectronics (NYSE: STM), a global semiconductor leader serving customers across the spectrum of electronics applications, in collaboration with trusted partners, has created a complete ecosystem for securely connecting Industrial IoT (IIoT) and automotive systems to
MUNICH and SAN FRANCISCO, February 25, 2019 – tyntec, a global cloud communications provider, and Averon, developer of the world’s first fully automated security solution, today announced their strategic technology partnership. Leveraging tyntec’s extensive wireless carrier connectivity, the partnership will drive
14 Sep 2018 - Truphone to license remote eSIM provisioning platform and SIM operating system (OS) to Workz Group to deliver solutions to growing eSIM market. Global SIM technology provider, Truphone, today announces a partnership with Workz Group, the Dubai-based
MOUNTAIN VIEW, Calif., and SAN JOSE, Calif., May 2, 2017 /PRNewswire/ -- Highlights: JavaCard/GlobalPlatform OS optimized for Synopsys' ARC SEM processors enables deployment of highly secure SoCs capable of thwarting malicious hardware and software attacks ARC SEM processors incorporate a variety of advanced
Paris, France, 6 September 2016 - Today FAMOCO, the leader of secure Android devices, announced the launch of two new NFC readers, the FX200 and FX300, to complement the existing FX100. With strong growth internationally, FAMOCO is now present in
Amsterdam, April 5, 2016 – Gemalto (Euronext NL0000400653 GTO), the world's leading digital security company, today announced that Chief Executive Officer Olivier Piou has decided to retire from the Company at the end of August, 2016. Mr. Philippe Vallée, currently Chief