Accessing secure network areas by utilizing mobile-device authentication

One or more media is provided for granting a user access to a secured portion of a website. Initially, a request to access is received from a user, where the request is typically composed of access information (e.g., user ID, password). Incident to receiving the request for access, a subscriber server initiates a request to validate a set of security credentials. One security credential may be a device identifier sent to a communications network in response to a user being conveyed a dial-in number. This device identifier may be extracted from a communication transmitted from the mobile device and validated by leveraging the communications network authentication procedure. Authentication is utilized to verify the identity of the user. Additional security credentials may also require satisfaction before granting a requesting user access. For instance, satisfaction may include comparing access information within a user request against the set of security credentials.