- Key Parts:

UbiSec&Sens will address these areas by specification, validation (using formal logics) and network simulation. UbiSec&Sens will also prototype implementations on emulators and on actual sensor networks. The key research issues of UbiSec&Sens for developing secure sensor networks are:

  • Flexible routing and in-network processing

    • Routing schemes must be flexible enough to cope with gradually or abruptly disappearing nodes. System robustness is a pre-requisite for any form of self-healing. Within the framework of UbiSec&Sens we understand the gluing of routing and in-network processing as a mandatory pre-requisite for all types of WSNs. Another issue is the shorter life time of aggregator nodes due to their higher energy consumption. Re-election of these nodes after they stopped working must be guaranteed. This mechanism helps to flatly balance the energy-consumption in the WSN. UbiSec&Sens will provide an integrated solution for routing, in-network processing and aggregator node election.

  • Concealed data aggregation

    • It is one major objective to provide, for WSN applications with different security and reliability requirements, enhanced mechanisms for a concealed end-to-end encryption of reverse multicast traffic. Such mechanisms should provide a good balance between energy-efficiency and an appropriate level of security by still allowing in-network processing when forwarding data.

  • Data aggregation based on discrepancy query and multiple monitoring sensors

    • For a condensed representation and transmission of the monitored data, it is useful to transmit more than one type of values, e.g. temperature and humidity within one message. It may even be beneficial to transmit only discrepancy values from a pre-defined basis, since this helps to reduce the amount of data to be transmitted. Both design decisions have impact on the in-network processing of encrypted data. In UbiSec&Sens, we will provide solutions for data aggregation based on discrepancy query and multiple monitoring sensors.

  • Secure distributed data storage

    • There is a need to securely store monitored data in a distributed way whenever it is either not desired or simply not possible to transmit regional volatile information to an authorised consuming party in real-time. In particular, for WSN applications with asynchronous character, the WSN itself needs to store the monitored data. Considering the fact that nodes may disappear over the time, a secured and replicated but yet space- and energy-efficient storage of this information is an issue here. In UbiSec&Sens we will provide encrypted and distributed data storage mechanisms taking into account the volatile character of the WSN.

  • Enhanced key pre-distribution

    • It is not possible for the manufacturer to configure all the sensitive information e.g. keys before the WSN is rolled-out. Some sensitive information can only be distributed and stored with respect to the final position of the nodes within the network topology. Also the traffic flow pattern of the network is a parameter that needs to be considered when distributing keys for different security issues. In UbiSec&Sens we will implement and simulate key pre-distribution protocols considering the traffic pattern within WSNs.

  • Data plausibility

    • For some applications it is required to check the plausibility of the received and aggregated data at the sink node. Since a plausibility check as a necessary pre-requisite always requires the transmission of at least some redundant information we have to face an accuracy versus efficiency trade-off here. In addition, a plausibility check always needs to consider the semantic of the WSN application. UbiSec&Sens will investigate dependencies and trade-offs for a reasonable accurate and efficient plausibility check at some well-defined points of the WSN, and provide respective solutions. Research is done by analytical work and simulation.

  • Provably secure routing

    • Routing is one of the most basic networking functions in multi-hop sensor networks. The presence of malicious nodes must be considered and precautions be taken. Routing has two main functions: finding routes to the base stations (sink nodes), and forwarding data packets on these routes. UbiSec&Sens focuses on realising security of the first function: How to find routes to the base station in the presence of a malicious node(s).

  • Resilient data aggregation

    • The problem of resilient data aggregation is to perform data aggregation in the presence of an adversary that can modify the input data to the aggregation function. Aggregation is usually performed at base stations, but it is also envisioned that it can partially be performed by the sensors in the network (in-network processing). UbiSec&Sens provides solutions for resilient data aggregation with a minor rate of false negatives.

  • Pairwise/groupwise authentication or re-recognition

    • In the most general case, nodes need to build up a well-defined security association without any pre-established secret or common security infrastructure. In this case, pairs of entities will establish pair wise relationships. It is also conceivable that, once enough pair-wise relationships are established, groups of entities are able to establish new relationships. UbiSec&Sens will provide authentication protocols with an appropriate security level, yet being efficient in terms of energy-consumption and storage requirements.

  • Energy-efficient components

    • Hardware accelerators and software modules are both in the scope of UbiSec&Sens. Hardware accelerators can help reducing the energy consumption caused by a sensor node’s CPU. Software modules may help increasing the entropy of transmitted data, e.g. by avoiding an unreasonable ratio of padding information with respect to monitoring data due to an improper usage of an encryption mechanism. We have chosen three different WSN applications that serve as a requirement guide to address multilevel security and multilateral security in distributed systems.


    The ultimate aim of UbiSec&Sens is to provide a WSN security and reliability tool-box with modules addressing the above listed research topics. We will provide an “extended Lab trial” for two of these applications serving as a proof-of-concept to ensure an impressive demonstration of the social/economic potential of the WSN technology.

    <<  back  
    Final audit with a live outdoor demo for roadside WSN to vehicular communication: 17/18 December at NEC, Heidelberg, Germany.
    Selected software modules of the UbiSec&Sens security and reliability toolbox are available for download.
    UbiSec&Sens security and reliability toolbox has been presented at the ZigBee Alliance member meeting in Vancouver, BC, Canada, October 6-9, 2008 (Slides).
    The Agriculture WSN prototype has been reported in the German Viniculture Magazine "Der Deutsche Weinbau".
       © 2006 UbiSec&Sens Impressum