Models to Combat Email Spam Botnets and Unwanted Phone Calls

With the amount of email spam received these days it is hard to imagine that spammers act individually. Nowadays, most of the spam emails have been sent from a collection of compromised machines controlled by some spammers. These compromised computers are often called bots, using which the spammers can send massive volume of spam within a short period of time. The motivation of this work is to understand and analyze the behavior of spammers through a large collection of spam mails. My research examined a the data set collected over a 2.5-year period and developed an algorithm which would give the botnet features and then classify them into various groups. Principal component analysis was used to study the association patterns of group of spammers and the individual behavior of a spammer in a given domain. This is based on the features which capture maximum variance of information we have clustered. Presence information is a growing tool towards more efficient communication and providing new services and features within a business setting and much more. The main contribution in my thesis is to propose the willingness estimator that can estimate the callee's willingness without his/her involvement, the model estimates willingness level based on call history. Finally, the accuracy of the proposed willingness estimator is validated with the actual call logs

Sharing our digital aura through social and physical proximity

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2008.Includes bibliographical references (p. 153-160).People are quite good at establishing a social style and using it in different communications contexts, but they do less well when the communication is mediated by computer networks. It is hard to control what information is revealed and how one's digital persona will be presented or interpreted. In this thesis, we ameliorate this problem by creating a "Virtual Private Milieu", a "VPM", that allows networked devices to act on our behalf and project a "digital aura" to other people and devices around us in a manner analogous to the way humans naturally interact with one another. The dynamic aggregation of the different auras and facets that the devices expose to one another creates social spheres of interaction between sets of active devices, and consequently between people. We focus on the subset of networking that deals with proximate communication, which we dub Face-to-Face Networking (FtFN). Network interaction in this space is often analogous to human face-to-face interaction, and increasingly, our devices are being used in local situations. We describe a VPM framework, key features of which include the incorporation of trust and context parameters into the discovery and communication process, incorporation of multiple contextunique identities, and also the support for multiple degrees of security and privacy. We also present the "Social Dashboard", a readily usable control for one's aura. Finally, we review "Comm.unity", a software package that allows developers and researchers easy implementation and deployment of local and distant social applications, and present two applications developed over this platform.Nadav Aharony.S.M