Control systems and methods for blood or fluid handling medical devices

A method for protecting a medical device having a processor from malicious software, the method comprising:

• providing at the medical device at least one control software module that controls the operation of the medical device and is executable on the processor, and a remote access application that manages data flow between the at least one control software module and exterior sources, and is arranged to check for update files from a remote server, and has access to only predetermined memory locations in the medical device for update files received from the exterior sources;
• creating an update request file for uploading to the remote server by the remote access application to check for updates from the remote server;
• continuing to create and send the update request file at a predefined rate until a stop polling is called;
• enabling a communications link from the medical device to the remote server;
• activating the remote access application to transmit the update request file to the remote server via the enabled communications link, receive files from the remote server, and store the received files from the remote server in the predetermined memory locations;
• validating the received files, with the remote access application, prior to transferring the received files stored within the predetermined memory locations into an internal memory location accessible by the at least one control software module;
• reading the received files into the internal memory location if the received files are validated by the remote access application for storage within the internal memory location;
• deleting all received files in the predetermined memory locations if any part of validation fails;
• and
• disabling the communications link when a therapy using the medical device is started, and enabling the communications link after the therapy has ended.