In one embodiment, a method includes receiving a request for a client device to access a communication network. One or more of the computing devices is associated with a social-networking system, and the request includes data identifying the client device based on a certificate signed by one or more of the computing devices associated with the social-networking system. The method also includes associating the access request with a user profile of the social-networking system based on the certificate signed by one or more of the computing devices associated with the social-networking system; and granting the client device access to the communication network based at least in part on the association of the access request to the user profile.