US Patent 9659160 System and methods for authentication using multiple devices

A system and method of authentication using an authenticator computing device and at least two registered user devices is described. In operation, the authenticator computing device receives a request to access a resource from one of a plurality of user devices registered to a user. The authenticator computing device generates an authentication challenge in response to the request and the authentication challenge is then transmitted to a subset of the plurality of user devices. One or more of the user devices then subsequently generates and transmits a response to the authentication challenge to the authenticator computing device. The authenticator computing device then determines whether the responses received from the one or more user devices in the subset constitutes a valid response and then grants one or more of the user devices access to the resource if the responses received from the user devices constitutes a valid response to the authentication challenge.