The MACHINE Project


The purpose of the MACHINE Project is to provide a real-world support to collaborative networking, based on the dynamic and autonomous management of networking capabilities; in particular we aim to support
  • infrastructure/adhoc hybrid connectivity,
  • multi-hop paths,
  • heterogeneous interfaces.

Let us stress our purpose is twofold:
  1. providing an effective middleware implementation supporting collaborative scenarios
  2. providing an unifying model able to consider infrastructure/adhoc connectivity via single/multi hop paths and based on heterogeneous wireless interfaces.
While these pages briefly sketches our proposed model and its implementation, we provide even a deep investigation of the current literature based on the proposed model. If you are interested in our model and survey, please refer to the paper below. Paolo Bellavista, Antonio Corradi, Carlo Giannelli: A Unifying Perspective on Context-aware Evaluation and Management of Heterogeneous Wireless Connectivity, IEEE Communications Surveys and Tutorials, Vol. 13, No. 3, pp. 337-357, Third issue 2011.
[pdf paper @ IEEE]

To better understand the motivations pushing our MACHINE Project consider that, nowadays, mobile users willing to access Internet-based services via their portable wireless devices have to explicitly and directly take connectivity management decisions. For instance, one user has to switch on one of the wireless interfaces available on her laptop, e.g., the Wi-Fi card; then, she has to command the discovery of the set of currently available Wi-Fi Access Points (APs) and to decide which one to connect to. We claim that this situation is unacceptably limited for the application scenarios envisioned for the near future. On the one hand, the appropriateness of leaving the burden of explicit connectivity management decisions to final users is questionable. On the other hand, current scenarios only consider opportunities of direct Internet connectivity (APs are at the edges of the wired network infrastructure) with clients that can exploit only one interface at a time (Homogeneous Single-hop Wireless Internet - HSWI).

We claim that the progress in wireless technologies is pushing towards more complex, flexible, and collaborative deployment scenarios than HSWI, where
  1. clients are equipped with and able to simultaneously exploit several heterogeneous interfaces, and
  2. connectivity opportunities include both infrastructure-based equipment, e.g., IEEE 802.11 APs or UMTS base stations, and wireless peers offering connectivity in ad-hoc mode.
These connectivity opportunities, which we call connectors, could be profitably combined together at runtime, to establish dynamic chains of multi-hop peers forwarding traffic to/from the wired Internet. In the following, we indicate this envisioned scenario as Heterogeneous Multi-hop Wireless Internet (HMWI), because it simultaneously involves different wireless technologies, e.g., a client connected in Wi-Fi ad-hoc mode to a peer that dynamically decides to offer itself as Internet gateway via its UMTS modem. In other words, given the multiplicity of wireless interfaces and the increasing client-side computing resources, there is the need of middleware supports that exploit at best the potential of any available HMWI connector in a mixed infrastructure/ad hoc manner, even without affecting final users and service developers. Let us call channels the logical abstractions providing applications with the needed connectivity by physically involving a heterogeneous set of interfaces/connectors; we will use the term channel management middleware to indicate the support infrastructure needed for seamless channel determination, selection, and dynamic re-qualification, with no impact on application logic.