FLAVIA aims at understanding i) how to execute these MAC and higher-PHY programs without being forced to inject code in the hardware/firmware platform (called link processor) of the wireless device, ii) how to build, on top of this new concept, a MAC/higher-PHY design based on highly reusable modules and functionalities, and iii) how to “virtualize” radio primitives and resources so that different wireless access protocol stacks may coexist over a same wireless link processor. The FLAVIA vision will be evaluated by considering, as use cases, the architecture redesign of two current widespread technologies, namely 802.11 and 802.16/LTE, adopted respectively as reference for ad-hoc and infrastructure network scenarios. The work will be focused on the design of modules and interfaces enabling an easy implementation of the technology extensions proposed by the standardization bodies and by the research community, and new tailored functionalities needed in specific service contexts. Two parallel activities will make possible the architecture design and its refinements: i) the research work on optimization algorithms to be implemented in existing and future wireless technologies; ii) the actual prototyping of interfaces and replaceable modules for the 802.11 and 802.16 technologies. As a final step we will stress the FLAVIA architecture “on the field”, by implementing and testing our flexible architecture under different network “programs” and scientific solutions.
The FLAVIA architecture
To reach the project goals, we envision a system architecture, composed of:
- a “wireless link processor”, namely a hardware/firmware core exposing a (partially open) library of basic elementary operations on the wireless resources (low-level interface), operations today embedded in existing commercial wireless devices and cards, and hence not directly accessible and composable;
- a set of highly organized, clearly specified, and replaceable software “plug-in” modules, defined on the basis of the core operations, and designed to separately implement dedicated tasks, to be exploited for channel access operations and radio resource control. Examples of these tasks are frame timing, frame scheduling and prioritization, handshake and low level per-frame signalling, power tuning, spectrum resource allocation, etc. The modules expose a configuration and programming interface (high-level interface) to either complementary modules as well as higher layers;
- an associated set of control primitives for capability discovery and negotiation, to achieve interoperable communication and networking across possibly differently equipped devices as well as dynamic module configuration and launching for run-time adapting, upgrading or customizing the wireless nodes belonging to a network.
FLAVIA main expected impact is to concretely enable a change of the one-for-all design principle which has somehow inspired past generation networks, by permitting widely different wireless access operation as well as functional/performance improvements to be rapidly deployed and rolled out without requiring costly changes of underlying hardware devices.
Goal of these adaptations is addressing the complexity of unpredictable and fast-evolving application requirements, as well as the integration of heterogeneous and dynamically composed environments. We believe that the ability to provide wireless networking support, tightly adapted and optimized to the specific context envisioned, might boost the emergence of what we call “service-specific wireless networking support”. This would be highly beneficial for several already existing services and contexts (such as VoIP, gaming, cooperative computing, industrial automation, etc), which mandate for a much tighter flexibility than what is natively offered by existing wireless technologies. The paradigm shift envisioned by FLAVIA will be also pursued in the relevant standardization bodies (e.g., IEEE 802.11, 802.16 and 3GPP) as well as in their associated interoperability certification forums (e.g., WiFi Alliance, WiMAX Forum and LSTI).