Secure networked respiratory therapy systems

Inventors

HICKEY, Brian • Roberts, Christopher John • Somaiya, Chinmayee • Trull, Wendall Eric • Tucker, Luke Anthony • FERNANDO, Amila Jeewaka

Assignees

Resmed Inc

Abstract

Methods and apparatus provide communications among respiratory therapy device (“TD”), server and intermediary (e.g., a control device (“CTLD”) for the therapy device) to improve security. More secure communication channel(s) may be established using shared secrets derived with different channels. The communications may include transmitting therapy data from TD to server for authentication. The CTLD may receive the data and a nonce from a server. The CTLD receives from the TD a signing key dependent on the nonce and a secret shared by TD and server. The CTLD generates an authorisation code with received therapy data and the key for authentication of the data by the server upon its receipt of the code and data. The server computes (1) a key from the nonce and the secret known to TD, and (2) another authorisation code from received therapy data and the key. Data authentication may involve comparing received and computed codes.

Core Innovation

A secure networked respiratory therapy system is described in which a respiratory therapy device provides respiratory therapy and generates therapy data that is uploaded to a remote server. The control device receives the therapy data from the respiratory therapy device, receives a signing key based on a secret known to the respiratory therapy device and the remote server, generates an authorisation code using the therapy data and the signing key, and sends the therapy data and the authorisation code to the remote server.

The remote server is described as authenticating the therapy data by receiving the therapy data and a first authorisation code, computing a signing key from a nonce and a secret known to the respiratory therapy device, computing a second authorisation code based on the therapy data and the signing key, and comparing the first authorisation code with the second authorisation code. Authentication of the therapy data is performed when the codes match based on the comparison.

The document further describes cryptographic authentication logic for generating and validating the authorisation code, including hashed message authorisation codes produced using a cryptographic hash function and comparison variants using an exclusive OR. It also describes secure firmware upgrade authorization and therapy data upload authorization that rely on server-derived authorization codes using respiratory-therapy-device secrets, and uses nonce/offset values with expiration checks.

Claims Coverage

The independent claims cover four closely related implementations centered on receiving therapy data, deriving signing keys from a shared secret, generating an authorisation code, and authenticating the therapy data by code comparison. Across these independent claims, the inventive features repeatedly include nonce/offset-based signing-key derivation, cryptographic authorisation-code generation, and server authentication by comparison.

Taken together, the independent claims focus on authenticating uploaded therapy data using an authorisation code generated from therapy data and a signing key derived from a secret shared between the respiratory therapy device and the remote server, with server-side authentication achieved by computing a second authorisation code and comparing it to a first authorisation code.

Stated Advantages

Documented Applications