Contiki Ring File System for Real-Time Applications

Wireless Sensor Nodes often need to store or cache measurement or operational data into some non-volatile memory. Many applications using low power sensor nodes are based on Contiki, which provides the COFFEE file system for data storage. As COFFEE introduces occasional long and hard to predict write delays, it can not be used in applications which have real time demands, such as sensor networks operating in industrial environments. In this paper we present an efficient implementation of a flexible Ring File System for Contiki, that can be used in real-time applications. Read and write times are predictable and adherence to Contiki´s file system API allows it to be used as a drop-in replacement for COFFEE in many applications.