This disclosure describes techniques for authenticating one or more devices of a user in association with cloud computing services. The techniques include generating credential portions. The credential portions may be used in a signing protocol between one of the user devices and a cloud authenticator. The signing protocol may generate a signature that may be used in authentication with a cloud computing service. In some cases, the credential portions may be shared with other devices of the user. As such, the cloud authenticate may assist multiple user devices to authenticate with the cloud computing service.