Project Abstract

The Wireless Mesh Network (WMN) paradigm has recently emerged as a viable and cost-effective means to deploy all-wireless network infrastructures. Key distinguishing feature of WMNs with respect to Ad hoc Networks is the usage of dedicated Mesh nodes, with specific functionalities and hardware capabilities, and possibly employing different wireless technologies for backbone communication and for relaying traffic generated by ordinary wireless clients.

This project is motivated by the recognition that WMNs can be deployed in widely different service scenarios, possibly characterized by contrasting, if not even opposite, requirements. Operators and Enterprises envision WMNs as a cost-effective extension of their access infrastructure. Conversely, communities and groups of people reuse the same Wireless Mesh technology to form a dynamic, self-organizing, and citizens-owned pervasive communication infrastructure. This latter scenario can radically change the future of the network, by assigning active roles to end-users even in activities such as network development, roll-out, and management, which have been traditionally taken care of by operators or providers through a centralized, server-rich, approach. The shared and distributed nature of the network ownership calls for a rethinking of basic network operation and control, to be provided in a fully-distributed, spontaneous, autonomic, server-less fashion. With all this in mind, our proposed research approach is highly innovative and sprawls in three strategic directions: i) research methodology, ii) characteristics of the addressed algorithms and protocols, and iii) strong attention towards exploitation.

In terms of methodology, the project will largely rely on an experimental approach based on i) the implementation of a custom prototype Mesh node developed over miniaturized embedded Linux boxes, and ii) on-field validation in both dedicated outdoor mesh network trials as well as in real-world wireless community networks. Indeed, simulation assessment of Mesh protocols and algorithms, although essential in understanding the effectiveness of the proposed solutions, must be complemented with thorough on-field experimentation, to capture the impact of unexpected, and hard to predict/simulate, link-level operation (possibly vendor-dependent, as emerged in recent experimental studies) on the proposed solutions.

Concerning algorithms and protocols, we will devise autonomic and distributed solutions amenable to fitting the needs emerging in situations where the network deployment occurs in a spontaneous and self-configuring manner through cooperation of independently owned/managed Mesh nodes (wireless communities being one among many use cases). When a network lacking centralized operation and control is being added requirements such as robustness to failures and link quality changes, the biggest challenge is achieving the following: performance effectiveness comparable to that of traditional operator-managed wireless access networks, scalability, and strong security/confidentiality features. To this end, we will adopt distributed, cross-layer approaches to tackle important problems related to spontaneous addressing, unicast/multicast routing, network self-configuration and load balancing, security, cooperation and trust, channel assignment, management of the user mobility, Medium Access Control and radio resource management through advanced antenna technologies, multi-rate support, and efficient delivery of real-time streaming services.

Finally, a distinguishing feature of our project is the special attention towards exploitation. To maximize the possibility of exporting our technology and solutions in the real world, we have set forth three strategies. First, we will provide open software/firmware running over off-the-shelf low-cost hardware. The ability for any end user to set-up a wireless Mesh node and participate to a wider networking infrastructure may foster a third tidal change after the first two observed in recent Internet history (i.e., user-managed peer-to-peer applications such as Skype and file sharing, and user-generated content such as YouTube, MySpace, etc.). The time for user-managed networks may just be ripe. Second, a modular implementation of protocols and algorithms as loadable libraries will allow flexible configuration and tailoring of the Mesh nodes depending on their deployment scenarios. Conflicting needs (e.g., a wireless community network scenario versus an enterprise wireless access network extension) may thus be addressed. Third, our nodes and solutions will be demonstrated in a real-world network deployment currently run by a leading Italian wireless community, with the further goal to involve highly-skilled community members in the maintenance and evolution of the project achievements even after the project's end.