What if the mobile phone card is degaussed?

When the SIM card of the mobile phone is damaged, you can bring the original mobile phone and ID card to the mobile communication business hall 100 for a replacement card.

1. Card replacement: refers to the business that needs to be replaced or reissued due to the loss or damage of the mobile phone SIM card (the original mobile phone number and tariff package remain unchanged);

Second, you can go to your current communication office 100 (not a mobile agent). Special numbers can only be handled at the designated communication office 100, and cannot be entrusted to others.

3. The original ID card registered with the mobile phone card should be provided when the card is replenished, and the service password or several telephone numbers frequently contacted in the near future should be provided. If the mobile phone number is in arrears, it must be paid first to deal with it;

Four, after the completion of the replacement card, the original SIM card will be invalid.

It is suggested that the management rules for card replacement vary from place to place, subject to the announcement of the business hall where the number belongs. For details, please consult 100 business hall or 10086.

Overview of sim card

SIM card is called "subscriber identification card", which is actually a smart card with large-scale integrated circuit, and is used to register important data and information of users. One of the most important functions of SIM card is authentication and encryption. When a user moves to a new area to make or receive a call, the switch must authenticate the user to determine whether it is a legitimate user. At this time, both SIM card and switch use authentication algorithm to calculate authentication key and 8-bit random number. If the calculation results are the same, the SIM card is identified, otherwise the SIM card is rejected and the user cannot make a call. SIM card can also use encryption algorithm to encrypt voice to prevent eavesdropping.

Functional embodiment

Specifically, its functions are mainly reflected in the following aspects. The data stored in the SIM card can be divided into four categories: the first category is fixed storage data. This kind of data is written by SIM card center before the mobile phone is sold, including international mobile subscriber identification number (IMSI), authentication key (KI), authentication and encryption algorithm, etc. The second category is temporarily stored network data. Such as location area identification code (LAI), mobile subscriber temporary identification code (TMSI) and public telephone network code without access. The third category is related business codes, such as personal identification number (PIN), unlocking code (PUK), billing rate, etc. The fourth category is the telephone book. Almost all the user's data are stored in SIM cards, so SIM cards are also called "subscriber data identification cards". SIM cards can be divided into big cards and small cards. Small cards are called "plug-in SIM cards", that is, chips on big cards.