Location based mobile computing - a tuplespace perspective

This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2006 IOS PressLocation based or "context aware" computing is becoming increasingly recognized as a vital part of a mobile computing environment. As a consequence, the need for location-management middleware is widely recognized and actively researched. Location-management is frequently offered to the application through a "location API" (e.g. JSR 179) where the mobile unit can find out its own location as coordinates or as "building, floor, room" values. It is then up to the application to map the coordinates into a set of localized variables, e.g. direction to the nearest bookshop or the local timezone. It is the opinion of the authors that a localization API should be more transparent and more integrated: The localized values should be handed to the application directly, and the API for doing so should be the same as the general storage mechanisms. Our proposed middleware for location and context management is built on top of Mobispace. Mobispace is a distributed tuplespace made for mobile units (J2me) where replication between local replicas takes place with a central server (over GPRS) or with other mobile units (using Bluetooth). Since a Bluetooth connection indicates physical proximity to another node, a set of stationary nodes may distribute locality information over Bluetooth connections, and this information may be retrieved through the ordinary tuplespace API. Besides the integration with the general framework for communication and coordination the middleware offers straightforward answers to questions like: Where is node X located? Which nodes are near me? What is the trace of node Y

Backscatter from the Data Plane --- Threats to Stability and Security in Information-Centric Networking

Information-centric networking proposals attract much attention in the ongoing search for a future communication paradigm of the Internet. Replacing the host-to-host connectivity by a data-oriented publish/subscribe service eases content distribution and authentication by concept, while eliminating threats from unwanted traffic at an end host as are common in today's Internet. However, current approaches to content routing heavily rely on data-driven protocol events and thereby introduce a strong coupling of the control to the data plane in the underlying routing infrastructure. In this paper, threats to the stability and security of the content distribution system are analyzed in theory and practical experiments. We derive relations between state resources and the performance of routers and demonstrate how this coupling can be misused in practice. We discuss new attack vectors present in its current state of development, as well as possibilities and limitations to mitigate them.Comment: 15 page

Improving security in data-centric storage for wireless sensor networks

This paper proposes a novel mechanism to provide with security to existing Data-Centric Storage (DCS) solutions for Wireless Sensor Networks. The goal is to achieve a high security level without modifying standard DCS premises or increasing the network overhead. This means we just use the messages an operations already defined by DCS solutions. Our goal is to fulfil two security requirements: (i) only legitimate nodes for an application should be able to access the information of that application, and (ii) avoid long-term Denial of Service attacks targeting an application that operates in the network. Toward this end we define two different solutions depending on whether the sensor nodes in the network are resource-limited or powerful. We run extensive simulations and discuss the efficiency of the proposed solution under two different DCS solutions: GHT that proposes to use a single and static storage node per application, and STARR-DCS that uses multiple storage nodes per application that in addition change over the time. Based on the obtained results and discussion we conclude that changing replication nodes over the time is by itself a smart approach to avoid long-term attacks.The research leading to these results has been partially funded by the Spanish MEC under the CRAMNET project (TEC2012-38362-C03-01) and by the General Directorate of Universities and Research of the Regional Government of Madrid under the MEDIANET Project (S2009/TIC-1468), NSERC DIVA Network Program, Canada Research Chairs Program, the Ontario Research Fund (ORF), ORNEC, the Early Ontario Researcher Award, the Ontario Centres of Excellence (OCE)