@INPROCEEDINGS{GiraoESAS2006,
  author = {Joao Girao and Miquel Martin},
  title = {Two's company, Three is a crowd: A group-admission protocol for {WSN}s},
  booktitle = {Security and Privacy in Ad-Hoc and Sensor Networks, 2006 ({ESAS} 2006)},
  year = {2006},
  volume = {4357/2006},
  series = {Lecture Notes in Computer Science},
  pages = {70-82},
  address = {Hamburg, Germany},
  month = {September},
  publisher = {Springer-Verlag},
  abstract = {Once a wireless sensor network (WSN) is stable and has been running
	for a while,sensors start to fail due to hardware problems, battery
	exhaustion or even due to their physical destruction. In any case,
	the administrator of the network may wish to replace the damaged
	nodes with new ones to reinforce the coverage area. In this paper
	we make use of an out of band channel (OOB) to bootstrap an authenticated
	symmetric key. The protocol ensures that the new sensor nodes are
	currently part of the region covered by the network before negotiating
	sensitive key material and making them a part of the system and its
	operations. We describe a novel approach to group admission for wireless
	sensor networks using an OOB secure channel and perform a security
	evaluation over this protocol.},
  doi = {10.1007/11964254_8},
  owner = {Miquel Martin},
  pdf = {http://www.springerlink.com/content/83g6283402t41167/fulltext.pdf}
}