VSPIN: A framework for developing incremental sensor network reprogramming strategies

We present VSPIN, a framework for developing incremental code update mechanisms to support efficient reprogramming of wireless sensor networks. The presentation emphasizes the supporting framework rather than the reprogramming mechanisms themselves. Concretely, VSPIN provides a modular testing platform on a host desktop system to plug-in and evaluate various incremental code update algorithms. The framework supports Avrdude, among the most popular programming tools for AVR microcontrollers. VSPIN consists of a virtual serial port device driver which executes in Linux kernel space, a user space component, and a corresponding boot loader which executes on the sensing (microcontroller) core. The framework is tailored for AVR microcontrollers, which support in-system reprogramming of on-chip flash memory through a serial interface (SPI or UART). On the host side, VSPIN can function with wireless communication devices (802.11b/g/n or 802.15.4), or wired communication devices which expose a serial device interface on the Linux platform (RS-232 or USB). We describe the overall architecture and detail the individual components of VSPIN. The development of VSPIN is the first such attempt to facilitate ease of development, testing, and use of incremental code update algorithms for efficient network reprogramming.