    @article {Zhou2007,
	title = {An Effective Multi-layered Defense Framework Against Spam},
	journal = {Information Security Technical Report},
	volume = {12},
	number = {3},
	year = {2007},
	pages = {179-185},
	publisher = {Elsevier},
	abstract = {<p>Spam is a big problem for email users. The battle between spamming and anti-spamming technologies has been going on for many years. Though many advanced anti-spamming technologies are progressing significantly, spam is still able to bombard many email users. The problem worsens when some anti-spamming methods unintentionally filtered legitimate emails instead! In this paper, we first review existing anti-spam technologies, then propose a layered defense framework using a combination of anti-spamming methods. Under this framework, the server-level defense is targeted for common spam while the client-level defense further filters specific spam for individual users. This layered structure improves on filtering accuracy and yet reduces the number of false positives. A sub-system using our pre-challenge method is implemented as an add-on in Microsoft Outlook 2002. In addition, we extend our client-based pre-challenge method to a domain-based solution thus further reducing the individual email users{\textquoteright} overheads.</p>
},
	keywords = {Network Security, Security service, Spam},
	issn = {1363-4127},
	doi = {10.1016/j.istr.2007.05.007},
	url = {http://www.sciencedirect.com/science/article/B6VJC-4NS2GR9-1/2/d542b6d1b936f796cad17284a6edbc69},
	author = {Jianying Zhou and Wee-Yung Chin and Rodrigo Roman and Javier Lopez}
}
@article {Roman2007a,
	title = {The Role of Wireless Sensor Networks in the Area of Critical Information Infrastructure},
	journal = {Information Security Technical Report},
	volume = {12},
	number = {1},
	year = {2007},
	pages = {24-31},
	publisher = {Elsevier},
	abstract = {<p>Critical Infrastructures, such as energy, banking, and transport, are an essential pillar to the well-being of the national and international economy, security and quality of life. These infrastructures are dependent on a spectrum of highly interconnected information infrastructures for their smooth, reliable and continuous operation. The field of protecting such Critical Information Infrastructures, or CIIP, faces numerous challenges, such as managing the secure interaction between peers, assuring the resilience and robustness of the overall system, and deploying warning and alert systems, amongst others. In this tapestry of CIIP, Wireless Sensor Networks can be used as an invaluable tool due to their intelligent distributed control capabilities, alongside with their capability to work under severe conditions. In this paper, we justify why Wireless Sensor Networks technology is suitable for providing security for these scenarios, describing both their advantages and research issues and their role in the overall scheme of protecting the Critical Information Infrastructures.</p>
},
	keywords = {Critical Information Infrastructure Protection, Network Security, wireless sensor networks},
	issn = {1363-4127},
	doi = {10.1016/j.istr.2007.02.003},
	url = {http://www.sciencedirect.com/science/article/B6VJC-4N6NK24-1/2/b1462973afe70af30a10b955d96ccbb6},
	author = {Rodrigo Roman and Cristina Alcaraz and Javier Lopez}
}
