Research master internship: Cooperation enforcement in opportunistic cooperative wireless networks
The last two decades have witnessed an unprecedented success of wireless networks due to the proliferation of inexpensive, widely available wireless devices. The deployment of 802.11- based network infrastructure is happening at a rapid rate with no sign of abatement. As a result, it is quite common nowadays to be within range of dozens of access points in many suburban areas.
Moreover, the recent proliferation of WLAN-enabled devices such as mobile phones and personal digital assistants (PDAs) is facilitating a wide range of emerging applications where the technology is used in the form of ad-hoc and mesh networks (collectively known as wireless multihop networks), from ad-hoc extension of cellular coverage to message exchange between personal mobile nodes to emergency communications in disaster zones.
Compared with the traditional point-to-point communication scenario, one striking feature of modern wireless communication networks is the share of a common medium among multiple users. In such context, the traditional layered network design paradigm is no more adaptable. The primary goal of this internship is thus to investigate the opportunistic cooperation, an important technique for wireless networks with unstable links that provides additional diversity against link outages by allowing nearby nodes that overhear the transmitted signal to make additional transmissions to assist in delivering the data to its destination.
More specifically, based on the interest of the student, the internship can be oriented towards the following two directions, each corresponding to a pressing research issue largely unexplored in existing literature.
• Virtually all related studies assume that relay nodes are willing to help the source and ignore the issue of their incentive to cooperate. This assumption fails in networks with selfish nodes, which may not be willing to relay packets for other nodes, e.g. due to the energy cost involved. The first direction is thus to addresses the problem of cooperation incentives in opportunistic cooperation for wireless networks, i.e., how to encourage network nodes to cooperate. The student is expected to design incentive mechanisms based on game theory and evaluate the performance of the proposed mechanisms via numerical analysis.
• The second direction is security, a pressing issue in opportunistic cooperation as misbehaving relay nodes can severely degrade the system performance. However, there exists no comprehensive analysis on the security risks and countermeasures in this context.
Moreover, the proposed security solutions for wireless networks are no more applicable to the source-opportunistic helper (relay node)-destination communication pattern in cooperative communication context. In this regard, the student is expected to provide a systematic analysis on the security issues in this novel context, based on which adapted security mechanisms and architectures will then be developed to detect the abnormal behaviour, and to trace adversarial relay nodes.
The internship is remunerated can be possibly extended to a Ph.D. thesis, depending on the results.
Contact:
Lin Chen (chen@lri.fr) Assistant professor
Laboratoire de Recherche en Informatique (LRI) Université de Paris-Sud XI
