What do mobile service passwords, PUK codes, PIN codes, SIM cards and GSM mean?

The full name of PUK code is PIN unlock code, which is usually an 8-digit decimal number, and its function is to unlock PIN. PIN code and PUK code are paired, and users can set the PIN code that needs to be input when starting the machine in the security setting options. It is a good protection habit to enter your own preset PIN code when turning on the phone, which can prevent illegal users from using this number when the mobile phone or card is lost.

PIM, English abbreviation, has many meanings. For example, PIM is also called PIMS, personal information manager in English and personal information manager in Chinese. IDMR (inter-domain multicast routing) working group designed a protocol-independent multicast PIM. PIM does not depend on a specific unicast routing protocol. Instead of maintaining a separate multicast routing table, PIM can use unicast routing tables established by various unicast routing protocols to complete the RPF check function. In addition, it refers to IC card, which is often used as PHS communication equipment.

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. SIM also refers to social impact marketing.

The full name of GSM is Global System for Mobile Communications, and Chinese is Global System for Mobile Communications, commonly known as "GSM". It is a technical standard of mobile communication originated in Europe, and it is the second generation of mobile communication technology. Its development purpose is to enable all parts of the world to use a mobile phone network standard together, so that users all over the world can use a mobile phone. At present, China Mobile and China Unicom each have a GSM network, which is the largest mobile communication network in the world. The GSM system includes GSM 900:900MHz, GSM 1800: 1800 MHz and GSM 1900: 1900 MHz. GSM is also the abbreviation of Guanghua School of Management in Peking University.

The service password is the customer identification password of China Unicom. In order to ensure your data security, you must pass the service password verification before you can handle business through various channels (business hall, 100 10 customer service hotline, online business hall, etc.). ). The service password you use in all channels (business hall, 100 10 customer service hotline, online business hall, etc.). ) is unified.

The act of verifying the service password before handling the business is regarded as the act authorized by the customer himself. Please keep your service password and modify it in time to protect your personal rights and interests.