Access control method and system

Access control system (1) for a spectator to a facility, comprising a validation server (2) and automatic access gates (3) to the facility, wherein the validation server (2) is configured to communicate with an application installed on a spectator's mobile device (1), and wherein the validation server (2) is configured to communicate with the automatic access gates (3),

• characterized in that
• it also includes a sensor (4) of a physical variable located in the facility,
• and in that the validation server (2) and the automatic access gates (3) are configured to carry out the following operations:
• one of the application of the mobile device (1) and the validation server (2) generates a seed(S) that constitutes a first portion of an entry code (EC), and sends said seed(S) to the other of the application of the mobile device (1) and the validation server (2);
• the mobile device (1) sends identification data (N, IMSI, IMEI) of the mobile device (1) to the validation server (2);
• the application of the mobile device (1) calculates an entry code (EC) of limited time duration, where the entry code (EC) comprises the seed(S), identification data (N, IMSI, IMEI) of the mobile device (1) and at least one first measurement of a physical variable (PV1) of the environment of the mobile device (1) obtained at that moment by means of a sensor embedded in said mobile device (1);
• when the mobile device (1) communicates the entry code (EC) to the automatic access gate (3) to the facility, the automatic access gate (3) sends a validation request that includes said entry code (EC) to the validation server (2);
• at that same moment, the sensor (4) located in the facility performs a second measurement of the physical variable (PV2) and communicates it to the validation server (2);
• the validation server (2) calculates, in the same way that the application of the mobile device (1) calculated the entry code (EC), a validation code (VC) corresponding to the time frame in which it receives the validation request comprising the seed(S), the identification data (N, IMSI, IMEI) of the mobile device (1), and the second measurement of the physical variable (PV2);
• and
• the validation server (2) checks if there is a coincidence between the entry code (EC) received from the automatic access gate (3) and the validation code (VC) calculated by the validation server (2) itself and, if so, it sends an access grant order to the automatic access gate (3), while if not, it sends an access denial order to the automatic access gate (3).