Wednesday, March 16, 2011

Types Of Phone Sim Cards

A SIM card or Subscriber Identity Module is a portable memory chip used in mobile phones. The SIM card makes it easy to switch to a new phone by simply sliding the SIM out of the old phone into the new one. A SIM card contains its unique serial number, internationally unique number of the mobile user or the service-subscriber key (IMSI), security authentication and ciphering information, temporary information related to the local network, a list of the services the user has access to and two passwords (PIN for usual use and PUK for unlocking). In simple terms, it holds personal identity information, cell phone number, phone book, text messages and other data. It can be regarded as a mini hard disk that automatically activates the phone into which it is inserted.

SIM cards are generally used with carriers that operate on the Global System for Mobile Communication (GSM) network. The competing network is Code Division Multiple Access (CDMA), a technology created by U.S. Company, Qualcomm. The first SIM card was created in 1991, with Munich-based smart card maker Giesecke & Devrient selling the first 300 SIM cards to Finnish wireless network operator Radiolinja.

SIM cards are available in three standard sizes. The first and the oldest are in the size of a credit card also known as full-size card (85.60 mm 53.98 mm x 0.76 mm). The development of physically smaller mobile devices prompted the development of a smaller SIM card, the mini-SIM card. It has the same thickness as the full-size cards, but a length of 25 mm and a width of 15 mm, and has one of its corners truncated (chamfered) to prevent misinsertion. The mini-SIM card has the same contact arrangement as the full-size SIM card and they are normally supplied within a full-size card carrier, attached by a number of linking pieces. This arrangement (defined in ISO/IEC 7810 as ID-1/000) allows for such a card to be used in a device requiring a full-size card, or to be used in a device requiring a mini-SIM card after cleanly breaking the scorings manufactured in the outline of a mini-SIM card.

The newest SIM card is known as the 3FF or micro-SIM, which has dimensions of 15 mm 12 mm. Most cards of the two smaller sizes are supplied as a full-sized card with the smaller card held in place by a few plastic links; it can easily be broken off to be used in a device that uses the smaller SIM. The specifications for the 3FF card or micro-SIM also include additional functionality beyond the physical card size.

8 comments:

  1. I think there are many types of sim cards . I mostly like Simple mobile sim cards . I say the Sim cards have long distance connectivity without any error. And also have Large contact memory.

    ReplyDelete
  2. Yeah you are right @ Sheikh there are so many type of Sims available in the market but no one are providing Cheap Calls to India ... So many destination like usa and uk are almo0st free to call but there are no way to Cheapest Pinless Calling to India ... please let me know about Calls Pinless to India ...

    ReplyDelete
  3. If any one want to recharge their cell phones visit this site Mobile recharge

    ReplyDelete
  4. I want to know how to make international calls from multiple registered numbers without using lengthy pin, password and calling cards numbers, Can anyone suggest me which one is the best Register phone service provider for international calling. It would be help full for me.

    ReplyDelete
  5. I am impressed your blog because your blog words is very impressiveness for business growths so thanks a lot for sharing this information.cheap Mobile cards
    buy calling cards

    ReplyDelete
  6. I am looking for a reliable connection for International calling which offers Cheap International Calls from Australia.Can anyone suggest me something?

    ReplyDelete
  7. mobile sim which type of Ram ??????

    ReplyDelete
  8. would any one tell me please a have a new mobile phone its supports 2 network sim cards but not pick others, is this a sim card issue or mobile issue?
    sim is middle size sim which means it is not micro sim card
    when i saw that sim which supports its chip's patron was different from the others. what is the cause mobile not pick other sim cards

    ReplyDelete