A system of authorizing access to a resource including a processor obtaining sensor information related to at least two users from one or more sensors, the sensor information including one or more of image information and proximity information of each of the at least two users. Further, an act of identifying current gestures is performed for each of the at least two users in accordance with the sensor information. The current gestures may be compared with pre-stored gesture information related to predetermined gestures and an order of the predetermined gestures. Further, access to the resource may be authorized when it is determined that the current gestures are in accordance with the predetermined gestures and the order of the predetermined gestures.