A device may receive, from a mobile device and via a first radio access network, a request for a service. The device may receive a mobile device identifier that identifies the mobile device on a second radio access network. The second radio access network may be a different type of radio access network than the first radio access network. The device may provide the mobile device identifier to an equipment identity register. The device may receive, from the equipment identity register, an authentication indicator that indicates whether to permit or deny access to the service by the mobile device and via the first radio access network. The device may selectively permit or deny the mobile device access to the service, via the first radio access network, based on the authentication indicator.