The Subscriber Identity Module (SIM) is just a smart card chip, of the size of a postage stamp, which when inserted in your mobile phone, forms the intelligent source of the various forms of communications. A Smart Card is a circuit card (ICC) and is defined as a miniature card with embedded integrated circuit. Though there are many applications, ICCs are catagorised into two broad segments. One could be the non-volatile memory card which contains only the storage components, and the other being a type of a microprocessor circuitry consisting of memory or microprocessor components Sim gia re.
The SIM is just a microprocessor unit with memory storage capability, which stores all the initial information about your account. It holds your identity in the form of your account number with the supplier and identifies you to the network. The currently available SIM card has 16 to 64 kb of memory, which stores your own personal telephone numbers that you call, text messages that you obtain or send and other value added services. There are often options given as value added services where you can download a picture or MP3 songs and even a band tome for your mobile. The memory storage for sale in your SIM card stores these data or information for you really to avail them as and when you require. There is a demand of larger memory spaces to store high resolution pictures, large MP3 files and also enable live video streaming.
Among the third generation cellular phone technologies is known as Universal Mobile Telecommunications System (UMTS). A Universal Subscriber Identity Module (USIM) is a credit card applicatoin for UMTS mobile telephony running on Universal Integrated Circuit Card (UICC). UICC is another type of chip smart card found in GSM and UMTs. Unlike SIM, this card features a huge memory space and holds a few kilobytes of data. With the coming of more services the storage space in the smart chip must be larger. In a GSM environment, the UICC has a credit card applicatoin of this of SIM where-as in a UTMS environment it is the USIM application. The SIM that you have is uniquely identified by its International Circuit Card ID (ICCID).
SIM cards are available on the cornerstone of a registration on signing a contract with the service provider. They’re available either on a pay-as-you-go basis, where you get your regular bills or as a pre-paid subscriber, where you spend a particular charge beforehand for the service that you want. This depends upon the kind of contract that you sign.
Two SIM cards may also be utilized in your mobile phone. All that’s necessary to complete is to buy dual SIM cover from your dealer for the style of the cellular phone that you have. It has many advantages viz. you may hold two SIM cards in a single cell phone, featuring pay-as-you-go and pre-paid as well, for your workplace and personal use respectively.
In most of the cases, the SIM could be taken off the mobile phone, enabling you to carry your mobile subscription and data through various kinds of cellphones that you could choose to have over the line of GSM phones available. It might so happen that the mobile phone with the SIM card in it’s misplaced somewhere, stolen or lost. You may, at the earliest, request the company to deactivate that SIM, providing them with the causes as to the reasons, and acquire another replacement card for your phone. You may well be liable to pay for a demand to the supplier for issuing the duplicate SIM card to you.
Generally the mobile phones available are’SIM unlocked’and as a result it works extremely well with any SIM card from any carrier in the world. Guided by the contract you sign, many cell phones are’SIM locked’by the company, and in most of the circumstances, till a particular contract period. These to will not use another SIM card as in the former case.