A data monitoring system comprising a server communicatively coupled to a client device and a data module via a network. The server is configured to store a private key of a public-private key pair associated with the data module, receive a request from the client device for authenticated access to the data module, and generate an authentication key based at least on the private key and a time. The client device is configured to generate the request for authenticated access to the data module and transmit the request to the server. The data module is configured to store the private key of the public-private key pair associated with the data module, generate the authentication key based at least on the private key and the time, and grant access to the data module if the authentication key generated by the data module and the authentication key generated by the server match.