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We present here a report produced by a workshop on 'Addressing failures in exascale computing' held in Park City, Utah, 4–11 August 2012. The charter of this workshop was to establish a common taxonomy about resilience across all the levels in a computing system, discuss existing knowledge on resilience across the various hardware and software layers of an(More)
In multihop wireless systems, such as ad-hoc and sensor networks, the need for cooperation among nodes to relay each other's packets exposes them to a wide range of security attacks. A particularly devastating attack is known as the wormhole attack, where a malicious node records control and data traffic at one location and tunnels it to a colluding node,(More)
Distributed systems with multiple interacting services, especially e-commerce systems, are suitable targets for malicious attacks because of the potential financial impact. Compared to intrusion detection, automated response has received relatively less attention. In this paper, we present the design of automated response mechanisms in an intrusion tolerant(More)
—There has been significant recent interest in covert communication using timing channels. In network timing channels , information is leaked by controlling the time between transmissions of consecutive packets. Our work focuses on network timing channels and provides two main contributions. The first is to quantify the threat posed by covert network timing(More)
— Wireless reprogramming of a sensor network is useful for uploading new code or for changing the functionality of existing code. Through the process, a node should remain receptive to future code updates because reprogramming may be done multiple times during the node's lifetime. Existing reprogramming protocols, such as Deluge, achieve this by bundling(More)
—Wireless reprogramming of sensor nodes is a requirement for long-lived networks due to changes in the func-tionality of the software running on the nodes. The amount of information that needs to be wirelessly transmitted during reprogramming should be minimized to reduce reprogramming time and energy. In this paper, we present a multi-hop incremental(More)
Wireless reprogramming of a sensor network is useful for uploading new code or for changing the functionality of existing code. Reprogramming may be done multiple times during a node's lifetime and therefore a node has to remain receptive to future code updates. Existing reprogramming protocols, including Deluge, achieve this by bundling the reprogramming(More)
This paper presents Chameleon, an adaptive infrastructure, which allows different levels of availability requirements to be simultaneously supported in a networked environment. Chameleon provides dependability through the use of special ARMORs—Adaptive, Reconfigurable, and Mobile Objects for Reliability—that control all operations in the Chameleon(More)
This paper presents a general knowledge model for propagating information in a content-based publish-subscribe system. The model is used to derive an efficient and scalable protocol for exactly-once delivery to large numbers (tens of thousands per broker) of content-based subscribers in either publisher order or uniform total order. Our protocol allows(More)