@conference {13391,
	title = {On Computing Compression Trees for Data Collection in Wireless Sensor Networks},
	booktitle = {2010 Proceedings IEEE INFOCOM},
	year = {2010},
	month = {2010/03/14/19},
	pages = {1 - 9},
	publisher = {IEEE},
	organization = {IEEE},
	abstract = {We address the problem of efficiently gathering correlated data from a wireless sensor network, with the aim of designing algorithms with provable optimality guarantees, and understanding how close we can get to the known theoretical lower bounds. Our proposed approach is based on finding an optimal or a near-optimal compression tree for a given sensor network: a compression tree is a directed tree over the sensor network nodes such that the value of a node is compressed using the value of its parent. We focus on broadcast communication model in this paper, but our results are more generally applicable to a unicast communication model as well. We draw connections between the data collection problem and a previously studied graph concept called weakly connected dominating sets, and we use this to develop novel approximation algorithms for the problem. We present comparative results on several synthetic and real-world datasets showing that our algorithms construct near-optimal compression trees that yield a significant reduction in the data collection cost.},
	keywords = {Approximation algorithms, Base stations, Communications Society, Computer networks, Computer science, computing compression trees, Costs, data collection, Data communication, data compression, designing algorithms, Educational institutions, Entropy, graph concept, Monitoring, Protocols, trees (mathematics), weakly connected dominating sets, Wireless sensor networks},
	isbn = {978-1-4244-5836-3},
	doi = {10.1109/INFCOM.2010.5462035},
	author = {Li,Jian and Deshpande, Amol and Khuller, Samir}
}
@conference {17531,
	title = {Fighting Spam with the NeighborhoodWatch DHT},
	booktitle = {IEEE INFOCOM 2009},
	year = {2009},
	month = {2009/04/19/25},
	pages = {1755 - 1763},
	publisher = {IEEE},
	organization = {IEEE},
	abstract = {In this paper, we present DHTBL, an anti-spam blacklist built upon a novel secure distributed hash table (DHT). We show how DHTBL can be used to replace existing DNS-based blacklists (DNSBLs) of IP addresses of mail relays that forward spam. Implementing a blacklist on a DHT improves resilience to DoS attacks and secures message delivery, when compared to DNSBLs. However, due to the sensitive nature of the blacklist, storing the data in a peer-to-peer DHT would invite attackers to infiltrate the system. Typical DHTs can withstand fail-stop failures, but malicious nodes may provide incorrect routing information, refuse to return published items, or simply ignore certain queries. The neighborhoodwatch DHT is resilient to malicious nodes and maintains the O(logiV) bounds on routing table size and expected lookup time. NeighborhoodWatch depends on two assumptions in order to make these guarantees: (1) the existence of an on-line trusted authority that periodically contacts and issues signed certificates to each node, and (2) for every sequence of k + 1 consecutive nodes in the ID space, at least one is alive and non-malicious. We show how NeighborhoodWatch maintains many of its security properties even when the second assumption is violated. Honest nodes in NeighborhoodWatch can detect malicious behavior and expel the responsible nodes from the DHT.},
	keywords = {Communications Society, computer crime, cryptography, Databases, IP addresses, IP networks, on-line trusted authority, Peer to peer computing, peer-to-peer computing, peer-to-peer distributed hash table, Postal services, Relays, Resilience, Routing, Security, table size routing, Unsolicited electronic mail},
	isbn = {978-1-4244-3512-8},
	doi = {10.1109/INFCOM.2009.5062095},
	author = {Bender,A. and Sherwood,R. and Monner,D. and Goergen,N. and Spring, Neil and Bhattacharjee, Bobby}
}
