MyCare Card design and media
See photographs of the MyCare Card prototypes.
Media type selection
According to the survey, conducted at Coventry University, smart card type of media was preferred over other proposed devices such as USB sticks, key fobs, jewellery and devices linked to a mobile phone.
Smart cards advantages
- common and widely accepted.
Smart cards disadvantages
- small memory size (mainly designed to store ID and security keys) which will only allow a limited number of medical records;
- slow data read/write rate;
- requires an external card reader for every computer type, and a card reader device driver installation;
- requires separate card browser installation (perhaps with Administrator/root access);
- only Microsoft Windows family of operating systems can be supported with the available resources and timing (due to the different driver requirements in different operating systems).
USB sticks advantages
- large memory (4GB and above). Thus, future-proof: enough to store medical images for example;
- high read/write speed;
- does not require external card reader for most computer types (including PDAs);
- does not require card browser installation: the card browser can be a portable application which runs from the card itself. (thus, no Administrator access required);
- most of modern operating systems can be supported (all Windows versions, Mac OS and Linux, i.e. those supported by Python/ wxPython).
USB sticks disadvantages
- less common;
- not widely accepted and trusted by the general population.
Additionally if the smart cards approach was taken, it would require the MyCare Card reader device, the firmware for the reader, the firmware for the card, the card reader Windows driver and the middleware which connects the driver and the MyCare Card Browser software. All of these will limit the usability and ultimately portability of the final system. With an USB stick, none of the above is required apart from the Card Browser software. The media interfacing infrastructure is already supported on every computer/mobile device with the USB bus and modern operating system.
Considering the advantages and disadvantages of traditional smart cards and modern USB sticks, the use of USB sticks is preferable. However, given the public’s preference for a smart card, a compromise had to be found between the two types of data storage. Going back to the end user survey it seemed that the major perceived difference between the devices was the shape and style, i.e. it was not related to the storage capacity, cost, connection type, or communication protocol. Thus, as a compromise a USB card design was chosen, which combines the advantages of both.
Card device interface
In this prototyping work, conventional USB mass storage protocol was utilized to store user's medical data, security and authentication data, and the browser software itself on the MyCare Card. All data is stored on the card in files, which are available to the operating system services via standard portable disk drivers. USB mass storage devices are natively supported by nearly any desktop operating system available today.
In further development, for security reasons, additional USB device protocols will need to be implemented. Those protocols will protect MyCare Card user medical data and software files from unauthorized access and from accidental corruption. Therefore, files access algorithms implemented in MyCare Card Browser software are isolated into interface classes to allow future embedding of such security protocols, without affecting other software parts or the overall source code structure.