Subscriber Identity Module

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Subscriber Identity Module

(telecommunications, wireless communications)
(SIM or "SIM card") A component, usually in the form of a miniature smart-card, that is theoretically tamper-proof and is used to associate a mobile subscriber with a mobile network subscription. The SIM holds the subscriber's unique MSISDN along with secret information such as a private encryption key and encryption/digital signature algorithms. Most SIMs also contain non-volatile storage for network and device management, contact lists, text messages sent and received, logos and in some cases even small Java programs.

SIM card

(Subscriber Identity Module card) A smart card that gives a cellphone its phone number and customer identity. Introduced in 1991 for GSM phones, most cards are removable. Satellite and LTE phones also use SIM cards. Activated by the cellular carrier, the SIM card contains a unique ID, authentication codes, network-specific data and the customer's phone contacts. See IMSI.

As long as users stay with the same carrier, they can generally switch their phone number and calling plan to a different phone by moving the SIM card. For travelers, prepaid SIM cards are available for unlocked phones, and phones that hold more than one SIM are also offered (see multi-SIM). In the early 1990s when cellphones were large, the first SIMs were the size of a credit card (1FF). See eSIM, SIM lock, R-UIM and smart card.

Mostly Nothing
A SIM is just a chip behind contacts. The rest is cardboard. Used for a while were Micro SIMs in a Mini SIM form factor (right).

Size   Thick   Form SIM Card         (mm)    (mm)   Factor

  Full Size        86x54   .76    1FF
  Mini (Standard)  25x15   .76    2FF
  Micro            15x12   .76    3FF
  Nano             12x9    .67    4FF
  Embedded   6x9  up to 1

Mini SIM
This Mini SIM was removed and flipped over to show the contacts and the six pins they press against.

Open the Case or Slide Out the Tray
Access to a SIM card is either from the inside by taking the back off or by inserting a pin into the side of the phone that releases the tray.

Prepaid SIM Cards
For travelers with unlocked Android and other GSM cellphones, prepaid SIM cards can be purchased.

Mini or Micro
A SIM card may come in both Mini and Micro SIM formats that can be punched out as required.
References in periodicals archive ?
He was referring to House Bill (HB) 7233, or the proposed Subscriber Identity Module (SIM) Card Registration Act.
One of the key features of GSM is the Subscriber Identity Module, commonly known as a SIM card.
It is increasingly difficult to identify personal from corporate data stored in embedded memory, subscriber identity module cards, removable storage, cloud services, and other locations.
This would not have had military significance, so the SIM (Subscriber Identity Module) cards might simply have been stolen by a member of the Pasdaran to get some free phone time.
Chairman Pakistan Telecommunication Authority (PTA) Ismail Shah has said that all the unverified SIMs will be blocked after April 12 and blocked SIMs will not be issued again before 6 months as biometric re-verification of Subscriber Identity Module (SIMs) enters in its final phase.
Gemalto makes SIM (Subscriber Identity Module) cards for phones and tablets as well as "chip and pin" bank cards and biometric passports.
By installing a Subscriber Identity Module (SIM) card loaded with this application, or a secure module, into the M2M equipment it is possible to protect data sent and received between such equipment, prevent tampering and realize a secure environment.
A growing number of Nigerians now own multiple Subscriber Identity Module (SIM) cards.
Giesecke & Devrient (G&D) and Verizon have deployed ruggedized 4G LTE Subscriber Identity Module (SIM) cards for use in mobile machine-to-machine (M2M) communications.
Combined with the proven reliability of smartphone subscriber identity module (SIM) technology, this trust-based TIP boundary creates an extremely secure mobile identity environment.
The right side of the iPhone 6 features a flat, centered subscriber identity module, or SIM, card tray like the iPhone 5, with the locations of the camera, microphone and rear flash located similarly to where they were on the latest-generation iPod touch.
February 9, 2013 (BOR) - South Sudan has begun a process of registering all telephone subscriber identity module (SIM) cards in use in the nation in order to track those responsible for issuing threat using mobile phones.

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