signed response (SRES)

The Signed Response (SRES) is a calculated confirmation signal sent from the mobile station to the Authentication Center( AUC) in a GSM network. This value is calculated from the random number(RAND) in conjunction with the secret subscriber key stored on the SIM card and the A3 algorithm, which is also stored, and is used by the Authentication Center for comparison and for granting network access authorization for the corresponding subscriber.