GSM is the acronym for Global System for Mobile Communications.It is a technology used in mobile phones and other mobile devices.It is most popular technology in the world.Originally GSM emerged in France by the Groupe Spécial Mobile.
Mobile stations and base stations
Once we know the concept of what GSM is, we talk about its function. The telephones that are used as mobile stations . For this station to be operational a SIM card is needed , which contains information about the terminal and its user. Information regarding the network operator, type of contract and other details are also recorded on the card.Each mobile station has a unique identifier, the IMEI . The cards also have their own international identifier, which can be transferred to another team without losing the information.
The SIM indicates to the base station,who is the user that communicates through it. This connection is made through radio waves.The base stations are networked through a controller. This is responsible for managing all resources so that communication make possible. At the same time, all the controllers are connected to a switching center via cable. The switches are controlled by the telephony operator, where all the data is collected and the identities of each SIM are verified.
What information does a SIM contain?
The SIM card is a chip in which essential information is saved so that the telephony service works. It also includes access data to unlock a terminal , without which the phone does not work.
Specifically in the SIM the phone number that the subscriber receives is recorded, an international code pair that can not be duplicated, which operator provides the service (which has its own code) and a security code. In addition to access passwords , the traditional 4-digit PIN to access the network and the PUK with which a terminal can be unlocked if necessary.
Beyond whether it is useful today or not, knowing what GSM is and how it works is necessary for those who want to be trained in the subject . It allows to know more advanced networks, which in some cases have been developed from this technology.