Analysis of different techniques to define metadata structure in NFC/RFID cards to reduce access latency, optimize capacity, and guarantee integrity

RFID/NFC cards/tags are widely used in a very diverse range of applications; these applications have usually a low data requirements, e.g. they are based on either just an ID for the data information or in a reduced and static set of fields. Therefore, the data structure can be easily defined and stored, without optimization needs, in the cards/tags. The problem with data structure appears when the application requirements define large, dynamic and miscellaneous information to be stored, such as an Electronic Health Record for e-Health application and a Truckload Record for Intelligent Transport Systems (ITS). Therefore, that information needs to be carefully stored to reach the register that we are looking for very quickly and to optimize the card/tag space, which is very constrained. Consequently, this paper proposes a set of design issues and techniques to define the metadata structure in NFC/RFID tags and cards to reduce search time, read time and optimize capacity. For this paper has been defined an example of the metadata structure from a Pharmaceutical Information System, where the patient card based on MiFare stores drugs history, patient allergies and general patient information. The reduction of space reached for this solution following the design issues and techniques in this paper has been about 189%, a reduction of time to find a register reaching a direct access to the records, instead of sequential search, and consequently a reduction for read time.