@conference {582, title = {Micro-Accreditation for Matching Employer E-Hire Needs}, booktitle = {2019 IEEE International Conference on Blockchain (Blockchain)}, year = {2019}, abstract = {

This paper presents a novel way to help match employers{\textquoteright} knowledge requirements with students{\textquoteright} knowledge earned using blockchain{\textquoteright}s smart contracts to assure credentials and track student records. This decentralized approach proposes using the micro-accreditation of topics from the CAE framework to courses and associated tasks, while introducing a revolutionary idea of a blockchain-based peer-reviewed rigor score assignment. Our work and result metrics were completed in Ethereum and connected test networks. We concluded this new approach is mostly efficient and scalable depending on the network load, with faster transaction times when the miners are properly incentivized. Future work will include further fine-tuning of the transaction algorithms to improve time, as well as an investigation into a better consensus model for peer review and rigor determination.

}, doi = {10.1109/Blockchain.2019.00054}, author = {Zaccagni, Zachary and Paul, Aditya and Dantu, Ram} } @conference {322, title = {A Decentralized Marketplace Application on the Ethereum Blockchain}, booktitle = {IEEE 4th International Conference on Collaboration and Internet Computing (CIC)}, year = {2018}, month = {10/2018}, publisher = {IEEE}, organization = {IEEE}, address = {Philadelphia, PA, USA}, abstract = {

Modern centralized online marketplaces such as eBay offer an alternative option for consumers to both sell and purchase goods with relative ease. However, drawbacks to these marketplaces include the platform{\textquoteright}s ability to block merchants at their own whim, the fees paid to the platform when listing a product and when selling a product, and the lack of privacy of users{\textquoteright} data. In this paper, we propose an application that remedies all three of these drawbacks through use of the Ethereum blockchain platform. The application was developed using the Truffle development framework. The application{\textquoteright}s functions were contained within an Ethereum smart contract, which was then migrated to the Ethereum network. The user{\textquoteright}s input was read through a web interface and sent to the Ethereum network via the web3.js API. Statistics about the application were gathered on the Rinkeby test network. The application was shown to have an average transaction runtime of 3.8 seconds, and an average gas consumption of 4.6 wei. Contract creation times for the application were shown to be less than a second. A cost analysis of the application was then conducted. The gas consumption of the transactions needed to both buy and sell a product was converted into US dollars, and the gas cost of the application was then compared to the cost to use an online auction marketplace such as eBay as well as an in-person auction house such as Sotheby{\textquoteright}s. The results showed that selling on the application is cheaper than existing online options as well as existing in-person options. These tests showed that our application was successful in addressing the drawbacks of current auction marketplaces.

}, keywords = {API, application program interfaces, auction marketplaces, average gas consumption, blockchain, centralized online marketplaces, Computer science, contract creation times, cost analysis, Cryptocurrency, decentralized, decentralized marketplace application, e-commerce, eBay, electronic commerce, Ethereum, Ethereum blockchain platform, Ethereum network, Ethereum smart contract, gas cost, human factors, in-person options, Internet, marketplace, Measurement, online auction marketplace, online options, peer-to-peer computing, Rinkeby test network, security of data, smart contract, Truffle development framework, user data, user interfaces, Web interface}, doi = {10.1109/CIC.2018.00023}, author = {Ranganthan, Vishnu Prasad and Ram Dantu and Paul, Aditya and Mears, Paula and Morozov, Kirill} } @article {376, title = {True Matching of Employers{\textquoteright} Needs}, year = {2018}, address = {Miami, Florida}, author = {Ram Dantu and Paul, Aditya} } @article {28, title = {Behavior-based Adaptive Call Predictor}, journal = {ACM Trans. Auton. Adapt. Syst.}, volume = {6}, year = {2011}, pages = {21:1{\textendash}21:28}, abstract = {

Predicting future calls can be the next advanced feature of the next-generation telecommunication networks as the service providers are looking to offer new services to their customers. Call prediction can be useful to many applications such as planning daily schedules, avoiding unwanted communications (e.g. voice spam), and resource planning in call centers. Predicting calls is a very challenging task. We believe that this is an emerging area of research in ambient intelligence where the electronic devices are sensitive and responsive to people{\textquoteright}s needs and behavior. In particular, we believe that the results of this research will lead to higher productivity and quality of life. In this article, we present a Call Predictor (CP) that offers two new advanced features for the next-generation phones namely {\textquotedblleft}Incoming Call Forecast{\textquotedblright} and {\textquotedblleft}Intelligent Address Book.{\textquotedblright} For the Incoming Call Forecast, the CP makes the next-24-hour incoming call prediction based on recent caller{\textquoteright}s behavior and reciprocity. For the Intelligent Address Book, the CP generates a list of most likely contacts/numbers to be dialed at any given time based on the user{\textquoteright}s behavior and reciprocity. The CP consists of two major components: Probability Estimator (PE) and Trend Detector (TD). The PE computes the probability of receiving/initiating a call based on the caller/user{\textquoteright}s calling behavior and reciprocity. We show that the recent trend of the caller/user{\textquoteright}s calling pattern has higher correlation to the future pattern than the pattern derived from the entire historical data. The TD detects the recent trend of the caller/user{\textquoteright}s calling pattern and computes the adequacy of historical data in terms of reversed time (time that runs towards the past) based on a trace distance. The recent behavior detection mechanism allows CP to adapt its computation in response to the new calling behaviors. Therefore, CP is adaptive to the recent behavior. For our analysis, we use the real-life call logs of 94 mobile phone users over nine months, which were collected by the Reality Mining Project group at MIT. The performance of the CP is validated for two months based on seven months of training data. The experimental results show that the CP performs reasonably well as an incoming call predictor (Incoming Call Forecast) with false positive rate of 8\%, false negative rate of 1\%, and error rate of 9\%, and as an outgoing call predictor (Intelligent Address Book) with the accuracy of 70\% when the list has five entries. The functionality of the CP can be useful in assisting its user in carrying out everyday life activities such as scheduling daily plans by using the Incoming Call Forecast, and saving time from searching for the phone number in a typically lengthy contact book by using the Intelligent Address Book. Furthermore, we describe other useful applications of CP besides its own aforementioned features including Call Firewall and Call Reminder.

}, keywords = {behavior, call logs, call matrix, convergence time, Prediction, trace distance}, issn = {1556-4665}, doi = {10.1145/2019583.2019588}, url = {http://doi.acm.org/10.1145/2019583.2019588}, author = {Phithakkitnukoon, Santi and Ram Dantu and Claxton, Rob and Eagle, Nathan} } @article {42, title = {Mobile Social Group Sizes and Scaling Ratio}, journal = {AI Soc.}, volume = {26}, year = {2011}, pages = {71{\textendash}85}, abstract = {

Social data mining has become an emerging area of research in information and communication technology fields. The scope of social data mining has expanded significantly in the recent years with the advance of telecommunication technologies and the rapidly increasing accessibility of computing resources and mobile devices. People increasingly engage in and rely on phone communications for both personal and business purposes. Hence, mobile phones become an indispensable part of life for many people. In this article, we perform social data mining on mobile social networking by presenting a simple but efficient method to define social closeness and social grouping, which are then used to identify social sizes and scaling ratio of close to {\textquotedblleft}8{\textquotedblright}. We conclude that social mobile network is a subset of the face-to-face social network, and both groupings are not necessary the same, hence the scaling ratios are distinct. Mobile social data mining.

}, issn = {0951-5666}, doi = {10.1007/s00146-009-0230-5}, url = {http://dx.doi.org/10.1007/s00146-009-0230-5}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @article {52, title = {Towards Ubiquitous Computing with Call Prediction}, journal = {SIGMOBILE Mob. Comput. Commun. Rev.}, volume = {15}, year = {2011}, pages = {52{\textendash}64}, abstract = {

With the long-awaited era of the pervasive computing approaches, the handheld devices such as personal mobile phones begin to evolve into ubiquitous computing devices. At this early stage of the evolution, we propose a model of a call predictor based on the naive Bayesian classifier. As an incoming call predictor, our model makes use of the user{\^a}€™s call history to generate a list of numbers/contacts that are the most likely to be the callers within the next hour. On the other hand, when the user wants to make an outgoing call (e.g., user flips open the phone or unlocks the phone, etc.), the outgoing call predictor generates a list of number/contacts to be called. Our model has been evaluated with the real-life call logs and it shows a promising result in accuracy.

}, issn = {1559-1662}, doi = {10.1145/1978622.1978628}, url = {http://doi.acm.org/10.1145/1978622.1978628}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @article {44, title = {ContextAlert: Context-aware alert mode for a mobile phone}, journal = {International Journal of Pervasive Computing and Communications}, volume = {6}, year = {2010}, month = {Sep}, pages = {1{\textendash}23}, abstract = {

Purpose {\textendash} Mobile computing research has been focused on developing technologies for handheld devices such as mobile phones, notebook computers, and mobile IP. Today, emphasis is increasing on context-aware computing, which aims to build the intelligence into mobile devices to sense and respond to the user{\textquoteright}s context. The purpose of this paper is to present a context-aware mobile computing model (ContextAlert) that senses the user{\textquoteright}s context and intelligently configures the mobile phone alert mode accordingly. Design/methodology/approach {\textendash} The paper proposes a three-step approach in designing the model based on the embedded sensor data (accelerometer, GPS antenna, and microphone) of a G1 Adriod phone. As adaptivity is essential for context-aware computing, within this model a new learning mechanism is presented to maintain a constant adaptivity rate for new learning while keeping the catastrophic forgetting problem minimal. Findings {\textendash} The model has been evaluated in many aspects using data collected from human subjects. The experiment results show that the proposed model performs well and yields a promising result. Originality/value {\textendash} This paper is distinguished from other previous papers by: first, using multiple sensors embeded in the mobile phone, which is more realistic for detecting the user{\textquoteright}s context than having various sensors attached to different parts of user{\textquoteright}s body; second, by being a novel model that uses sensed contextual information to provide a service that better synchronizes the user{\textquoteright}s daily life with a context-aware alert mode. With this service, the user can avoid the problems such as forgetting to switch to vibrate mode while in a meeting or a movie theater, and taking the risk of picking up a phone call while driving, and third, being an adaptive learning algorithm that maintains a constant adaptivity rate for new learning while keeping the catastrophic forgetting problem minimal.

}, issn = {1742-7371}, doi = {10.1108/17427371011084266}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @inbook {54, title = {Email Shape Analysis}, booktitle = {Distributed Computing and Networking: 11th International Conference, ICDCN 2010, Kolkata, India, January 3-6, 2010. Proceedings}, year = {2010}, pages = {18{\textendash}29}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Berlin, Heidelberg}, abstract = {

Email has become an integral part of everyday life. Without a second thought we receive bills, bank statements, and sales promotions all to our inbox. Each email has hidden features that can be extracted. In this paper, we present a new mechanism to characterize an email without using content or context called Email Shape Analysis. We explore the applications of the email shape by carrying out a case study; botnet detection and two possible applications: spam filtering, and social-context based finger printing. Our in-depth analysis of botnet detection leads to very high accuracy of tracing templates and spam campaigns. However, when it comes to spam filtering we do not propose new method but rather a complementing method to the already high accuracy Bayesian spam filter. We also look at its ability to classify individual senders in personal email inbox{\textquoteright}s.

}, isbn = {978-3-642-11322-2}, doi = {10.1007/978-3-642-11322-2_7}, url = {http://dx.doi.org/10.1007/978-3-642-11322-2_7}, author = {Sroufe, Paul and Phithakkitnukoon, Santi and Ram Dantu and Cangussu, Jo{\~a}o}, editor = {Kant, Krishna and Pemmaraju, Sriram V. and Sivalingam, Krishna M. and Wu, Jie} } @conference {40, title = {Mobile Social Closeness and Communication Patterns}, booktitle = {Proceedings of the 7th IEEE Conference on Consumer Communications and Networking Conference}, year = {2010}, publisher = {IEEE Press}, organization = {IEEE Press}, address = {Piscataway, NJ, USA}, abstract = {

As mobile networks expand rapidly to facilitate the rising number of mobile phone population, more mobile social services are being developed and offered. To create an efficient social functionality, characteristics of mobile social network must be studied. Social closeness is one of the basic fundamentals of any kind of social networking. In this paper, closeness in mobile social network is the subject of the study, from which social grouping scheme is proposed and validated against the feedbacks of human subjects. Based on the proposed grouping scheme, a study of the impact of the mobile social closeness to the similarity in calling patterns and reciprocity is presented.

}, isbn = {978-1-4244-5175-3}, url = {http://dl.acm.org/citation.cfm?id=1834217.1834285}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @conference {237, title = {Socio-technical aspects of video phones}, booktitle = {2010 Second International Conference on COMmunication Systems and NETworks (COMSNETS 2010)}, year = {2010}, month = {Jan}, abstract = {

The widespread use of voice over Internet protocol has paved the way for video over Internet protocol. In the past, certain technical shortcomings have prevented the popularity of videophones in the market. With present-day technology, videophones have just about everything required for day-to-day functions. Under such circumstances, certain socio-technical aspects require attention so that videophones can become as widespread and as technically streamlined as a plain old telephone system (POTS) with its additional benefits. A frequently brushed-upon topic is optimum features in the video phone for day-to-day social interactions. We carried out several experiments on different kinds of codecs and video formats to address two issues: i) the size of a video screen and ii) perception of motion and distance. From the measurements, we observed that a small frame rate with low bandwidth is adequate and can result in satisfactory video quality. We also observed that H263 performs well for all the day-to-day social networking activities. Standing 4 feet from the camera can still give reasonably good video quality in the currently available codecs. We believe that socio-technical issues will emerge more clearly over the next several years and they are germane to deployment of PC-based soft phones as well as hard phones.

}, keywords = {Bandwidth, Cameras, Codecs, Computer science, Internet telephony, plain old telephone system, Protocols, social aspects of automation, Social factors, social interactions, social issues, Social network services, social networking activities, sociotechnical aspects, Streaming media, technical issues, video codecs, video coding, video phones, video quality, Videoconference, videophone quality, videophones, videotelephony, voice over Internet protocol}, doi = {10.1109/COMSNETS.2010.5431971}, author = {Chandrasekaran, Vikram and Dantu, Siva and Kadiyala, Priyanka and Ram Dantu and Phithakkitnukoon, Santi} } @article {228, title = {Spam Classification Based on E-Mail Path Analysis}, journal = {Pervasive Information Security and Privacy Developments: Trends and Advancements: Trends and Advancements}, year = {2010}, pages = {332}, author = {Palla, Srikanth and Ram Dantu and Cangussu, Jo{\~a}o} } @conference {61, title = {Defense Against SPIT Using Community Signals}, booktitle = {Proceedings of the 2009 IEEE International Conference on Intelligence and Security Informatics}, year = {2009}, publisher = {IEEE Press}, organization = {IEEE Press}, address = {Piscataway, NJ, USA}, abstract = {

Internet telephony has recently gained popularity. Voice over IP (VoIP) has emerged as an alternative to the current public switched telephone network (PSTN) system due to its cost efficiency. Spam inherently becomes a problem in VoIP networks. In this paper, we present our ongoing research in defending VoIP networks against spam by presenting a new defense mechanism using community signals.

}, isbn = {978-1-4244-4171-6}, url = {http://dl.acm.org/citation.cfm?id=1706428.1706481}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @conference {29, title = {Email Shape Analysis for Spam Botnet Detection}, booktitle = {Proceedings of the 6th IEEE Conference on Consumer Communications and Networking Conference}, year = {2009}, publisher = {IEEE Press}, organization = {IEEE Press}, address = {Piscataway, NJ, USA}, abstract = {

Botnets have become the major sources of spamming, which generates massive unwanted traffic on networks. An effective detection mechanism can greatly mitigate the problem. In this paper, we present a novel botnet detection mechanism based on the email "shape" analysis that relies on neither content nor reputation analysis. Shape is our new way of characterizing an email by mimicking human visual inspection. A set of email shapes are derived and then used to generate a botnet signature. Our preliminary results show greater than 80\% classification accuracy (without considering email content or reputation analysis). This work investigates the discriminatory power of email shape, for which we believe will be a significant complement to other existing techniques such as a network behavior analysis.

}, isbn = {978-1-4244-2308-8}, url = {http://dl.acm.org/citation.cfm?id=1700527.1700792}, author = {Sroufe, Paul and Phithakkitnukoon, Santi and Ram Dantu and Cangussu, Jo{\~a}o} } @conference {238, title = {Adequacy of data for characterizing caller behavior}, booktitle = {Proceedings of KDD Inter. Workshop on Social Network Mining and Analysis (SNAKDD}, year = {2008}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @conference {17, title = {Behavior analysis of spam botnets}, booktitle = {2008 3rd International Conference on Communication Systems Software and Middleware and Workshops (COMSWARE {\textquoteright}08)}, year = {2008}, abstract = {

Compromised computers, known as bots, are the major source of spamming and their detection helps greatly improve control of unwanted traffic. In this work we investigate the behavior patterns of spammers based on their underlying similarities in spamming. To our knowledge, no work has been reported on identifying spam botnets based on spammerspsila temporal characteristics. Our study shows that the relationship among spammers demonstrates highly clustering structures based on features such as content length, time of arrival, frequency of email, active time, inter-arrival time, and content type. Although the dimensions of the collected feature set is low, we perform principal component analysis (PCA) on feature set to identify the features which account for the maximum variance in the spamming patterns. Further, we calculate the proximity between different spammers and classify them into various groups. Each group represents similar proximity. Spammers in the same group inherit similar patterns of spamming a domain. For classification into Botnet groups, we use clustering algorithms such as Hierarchical and K-means.We identify Botnet spammers into a particular group with a precision of 90\%.

}, keywords = {behavior pattern analysis, Botnets, Classification algorithms, clustering algorithm, Clustering algorithms, Correlation, Electronic mail, feature set, Filtering, information filtering, invasive software, maximum variance, pattern classification, pattern clustering, PCA, principal component analysis, spam filtering, Time frequency analysis, unsolicited e-mail, unwanted traffic control}, doi = {10.1109/COMSWA.2008.4554418}, author = {Husna, Husain and Phithakkitnukoon, Santi and Palla, Srikanth and Ram Dantu} } @inbook {46, title = {Behavioral Entropy of a Cellular Phone User}, booktitle = {Social Computing, Behavioral Modeling, and Prediction}, year = {2008}, pages = {160{\textendash}167}, publisher = {Springer US}, organization = {Springer US}, address = {Boston, MA}, abstract = {

The increase of advanced service offered by cellular networks draws lots of interest from researchers to study the networks and phone user behavior. With the evolution of Voice over IP, cellular phone usage is expected to increase exponentially. In this paper, we analyze the behavior of cellular phone users and identify behavior signatures based on their calling patterns. We quantify and infer the relationship of a person{\textquoteright}s randomness levels using information entropy based on the location of the user, time of the call, inter-connected time, and duration of the call. We use real-life call logs of 94 mobile phone users collected at MIT by the Reality Mining Project group for a period of nine months. We are able to capture the user{\textquoteright}s calling behavior on various parameters and interesting relationship between randomness levels in individual{\textquoteright}s life and calling pattern using correlation coeffi- cients and factor analysis. This study extends our understanding of cellular phone user behavior and characterizes cellular phone users in forms of randomness level.

}, isbn = {978-0-387-77672-9}, doi = {10.1007/978-0-387-77672-9_18}, url = {http://dx.doi.org/10.1007/978-0-387-77672-9_18}, author = {Phithakkitnukoon, Santi and Husna, Husain and Ram Dantu}, editor = {Liu, Huan and Salerno, John J. and Young, Michael J.} } @article {71, title = {Classification of phishers}, journal = {Journal of Homeland Security and Emergency Management}, volume = {5}, year = {2008}, abstract = {

Phishing attackers masquerade as genuine senders and try to steal consumers{\textquoteright} personal identity data and financial account credentials. In spite of aggressive efforts, technology companies have had limited success in restricting phishing attacks. Unfortunately the nature of phishing attacks changed over time from passive, such as password guessing and eavesdropping to active attacks, such as employing Trojans to intercept traffic and adopting social engineering techniques. No matter how many authentication techniques we develop, phishers always adapt. However, phishers cannot become part of the recipient{\textquoteright}s social network without consent. Though they can forge certain fields in an email header, phishers do not have access to the complete header. In this paper, we describe techniques for detecting phishers based on their traffic paths, traffic patterns, and on the receivers{\textquoteright} social network. Considering such issues, we based our solution on the trustworthiness of the relays participating in routing the emails. We examine the email{\textquoteright}s header rather than the content. We designed our classifier to perform the following analyses in four steps: i) DNS-header analysis, ii) Social network analysis, iii) Wantedness analysis, and iv) Proactive classification. We classify phishers into: i) Serial phishers, ii) Recent phishers, iii) Prospective phishers, and iv) Suspects. Finally, our classifier appends an alert level or label to the email{\textquoteright}s "subject" before adding the email to the inbox.

}, keywords = {application security, network security, phishing, spam}, author = {Ram Dantu and Palla, Srikanth and Cangussu, Jo{\~a}o} } @conference {50, title = {CPL: Enhancing Mobile Phone Functionality by Call Predicted List}, booktitle = {Proceedings of the OTM Confederated International Workshops and Posters on On the Move to Meaningful Internet Systems: 2008 Workshops: ADI, AWeSoMe, COMBEK, EI2N, IWSSA, MONET, OnToContent + QSI, ORM, PerSys, RDDS, SEMELS, and SWWS}, year = {2008}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {Berlin, Heidelberg}, abstract = {

In this paper, we present a concept of a new advanced feature for a mobile phone that provides its user functionality for predicting future calls. The feature is envisaged as a Call Predicted List (CPL) which makes use of the user{\textquoteright}s call history to build a probabilistic model of calling behavior based on the caller{\textquoteright}s calling patterns and reciprocity. The calling behavior model is then used to generate a list of numbers/contacts that are the most likely to be callers in the next hour. The performance of the CPL is evaluated with the real-life call logs and it shows promising results in accuracy.

}, keywords = {Call prediction, Context-aware computing, mobile phone}, isbn = {978-3-540-88874-1}, doi = {10.1007/978-3-540-88875-8_80}, url = {http://dx.doi.org/10.1007/978-3-540-88875-8_80}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @inbook {12, title = {Group Recommendation System for Facebook}, booktitle = {On the Move to Meaningful Internet Systems: OTM 2008 Workshops, Monterrey, Mexico, November 9-14, 2008. Proceedings}, year = {2008}, pages = {211{\textendash}219}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Berlin, Heidelberg}, abstract = {

Online social networking has become a part of our everyday lives, and one of the popular online social network (SN) sites on the Internet is Facebook, where users communicate with their friends, join to groups, create groups, play games, and make friends around the world. Also, the vast number of groups are created for different causes and beliefs. However, overwhelming number of groups in one category causes difficulties for users to select a right group to join. To solve this problem, we introduce group recommendation system (GRS) using combination of hierarchical clustering technique and decision tree. We believe that Facebook SN groups can be identified based on their members{\textquoteright} profiles. Number of experiment results showed that GRS can make 73\% accurate recommendation.

}, keywords = {decision tree, recommendation system, Social network}, isbn = {978-3-540-88875-8}, doi = {10.1007/978-3-540-88875-8_41}, url = {http://dx.doi.org/10.1007/978-3-540-88875-8_41}, author = {Baatarjav, Enkh-Amgalan and Phithakkitnukoon, Santi and Ram Dantu}, editor = {Meersman, Robert and Tari, Zahir and Herrero, Pilar} } @conference {49, title = {Inferring Social Groups Using Call Logs}, booktitle = {On the Move to Meaningful Internet Systems: OTM 2008 Workshops}, year = {2008}, month = {11/2008}, pages = {200{\textendash}210}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Monterrey, Mexico}, abstract = {

Recent increase in population of mobile phone users makes it a valuable source of information for social network analysis. For a given call log, how much can we tell about the person{\textquoteright}s social group? Unnoticeably, phone user{\textquoteright}s calling personality and habit has been concealed in the call logs from which we believe that it can be extracted to infer its user{\textquoteright}s social group information. In this paper, we present an end-to-end system for inferring social networks based on {\textquotedblleft}only{\textquotedblright} call logs using kernel-based na{\"\i}ve Bayesian learning. We also introduce normalized mutual information for feature selection process. Our model is evaluated with real-life call logs where it performs at high accuracy rate of 81.82\%.

}, isbn = {978-3-540-88875-8}, doi = {10.1007/978-3-540-88875-8_40}, url = {http://dx.doi.org/10.1007/978-3-540-88875-8_40}, author = {Phithakkitnukoon, Santi and Ram Dantu}, editor = {Meersman, Robert and Tari, Zahir and Herrero, Pilar} } @conference {30, title = {Privacy Management for Facebook}, booktitle = {4th International Conference on Information Systems Security (ICISS 2008)}, year = {2008}, month = {12/2008}, publisher = {Springer Berlin Heidelberg}, organization = {Springer Berlin Heidelberg}, address = {Hyderabad, India}, abstract = {

As more people adopt the Internet as a medium of communication, the Internet has developed into a virtual world and this has resulted in many online social networks (SN). MySpace and Facebook, two leading online SN sites, have a combined user base of 170 million as of 2008. SN sites started to offer developers open platforms that provide users{\textquoteright} profile information to the developers. Unfortunately, the applications can also be used to invade privacy and to harvest the users{\textquoteright} profile information without their acknowledgement. To address this vulnerability, we propose a privacy-management system that protects the accessibility of users{\textquoteright} profile. The system uses probabilistic approach based on information revelation of users. Our experimental result shows that the system can achieve high accuracy rate of 75\%.

}, keywords = {Facebook, Privacy, Privacy management, Social network}, doi = {10.1007/978-3-540-89862-7\_23}, author = {Baatarjav, Enkh-Amgalan and Ram Dantu and Phithakkitnukoon, Santi} } @conference {60, title = {Quantifying presence using calling patterns}, booktitle = {Communication Systems Software and Middleware and Workshops, 2008. COMSWARE 2008. 3rd International Conference on}, year = {2008}, month = {Jan}, abstract = {

Presence technology is going to be an integral part of the next generation of communication technology. It can eliminate telephone tag between two parties (caller and callee), which will increase productivity of the parties and reduce unnecessary bandwidth usage of unwanted calls. In this paper, we propose a Willingness Estimator that computes willingness level of a callee for receiving calls from a specified caller. By knowing the willingness value of the callee the caller can decide on proceeding with the call or not. The proposed Willingness Estimator is tested with real mobile user data, and these results are highly accurate. We measure willingness based on calling patterns (arrival time, location, day) of a caller to a callee and this could serve as one of the future presence based services. The results can be used in telecommunication networks such as PSTN, Cellular networks, and Voice over IP networks.

}, keywords = {cellular networks, Communications technology, Computer science, Computer security, Intrusion detection, Laboratories, Mobile handsets, mobile user data, Network servers, next generation communication, Next generation networking, presence technology, Productivity, PSTN, telecommunication networks, telephony, user calling pattern, voice over IP networks, willingness estimator}, doi = {10.1109/COMSWA.2008.4554403}, author = {Husna, Husain and Phithakkitnukoon, Santi and Baatarjav, Enkh-Amgalan and Ram Dantu} } @article {274, title = {Spam Classification Based on E-Mail Path Analysis}, journal = {International Journal of Information Security and Privacy (IJISP)}, volume = {2}, year = {2008}, month = {April}, pages = {46-69}, abstract = {

Email spam is the most effective form of online advertising. Unlike telephone marketing, email spamming does not require huge human or financial resources investment. Most existing spam filtering techniques concentrate on the emails{\^a}{\texteuro}{\texttrademark} content. However, most spammers obfuscate their emails{\^a}{\texteuro}{\texttrademark} content to circumvent content-based spam filters. An integrated solution for restricting spam emails is needed as content analyses alone might not provide a solution for filtering unsolicited emails. Here we present a new method for isolating unsolicited emails. Though spammers obfuscate their emails{\^a}{\texteuro}{\texttrademark} content, they do not have access to all the fields in the email header. Our classification method is based on the path an email traverses instead of content. Overall, our classifier produced fewer false positives when compared to current filters such as SpamAssassin. We achieved a precision of 98.65\% which compares well with the precisions achieved by SPF, DNSRBL blacklists.

}, doi = {doi:10.4018/jisp.2008040104}, url = {https://ideas.repec.org/a/igg/jisp00/v2y2008i2p46-69.html}, author = {Palla, Srikanth and Ram Dantu and Cangussu, Jo{\~a}o} } @conference {32, title = {Traffic Shaping of Spam Botnets}, booktitle = {2008 5th IEEE Consumer Communications and Networking Conference}, year = {2008}, month = {01/2008}, address = {Las Vegas, NV}, abstract = {

Compromised computers, known as bots, are the major source of spamming. Detecting them can help greatly improve control of unwanted traffic. In this paper, we develop a traffic control mechanism to detect and delay the traffic of suspicious senders and bots. By delaying spammer{\textquoteright}s traffic, it has been reported that 90\% of spam emails can be eliminated. In our proposed mechanism, we group spammers based on their behavior and transmission patterns. These patterns of spammers show high correlation between group members irrespective of geographic location, network ID, content, and kind of receivers. After identification of these botnet groups we applied traffic shaping techniques a pre-filtering analysis to avoid use of automated machines(bots) to spam a particular domain. Thus the source for majority of spam is blocked before reaching email servers. We also identify how randomly the botnets behave and how easy it is to capture a botnet behavior, based on Information theory. To our knowledge, there is no work reported on detecting and mitigating botnets based on their behavior and in particular transmission patterns.

}, keywords = {automated machine, compromised computer, E-mail server, Internet, prefiltering analysis, spam botnets, spammer traffic, spamming, suspicious senders, telecommunication network management, telecommunication traffic, traffic control mechanism, traffic shaping, unsolicited e-mail}, doi = {10.1109/ccnc08.2007.181}, author = {Husna, Husain and Phithakkitnukoon, Santi and Ram Dantu} } @article {43, title = {VoIP Security: Attacks and Solutions}, journal = {Information Security Journal: A Global Perspective}, volume = {17}, year = {2008}, pages = {114{\textendash}123}, abstract = {

Voice over IP (VoIP) technology is being extensively and rapidly deployed. Flexibility and cost efficiency are the key factors luring enterprises to transition to VoIP. Some security problems may surface with the widespread deployment of VoIP. This article presents an overview of VoIP systems and its security issues. First, we briefly describe basic VoIP architecture and its fundamental differences compared to PSTN. Next, basic VoIP protocols used for signaling and media transport, as well as defense mechanisms are described. Finally, current and potential VoIP attacks along with the approaches that have been adopted to counter the attacks are discussed.

}, keywords = {attack, defense mechanism, PSTN, Security, VoIP}, issn = {1939-3555}, doi = {10.1080/19393550802308618}, url = {http://dx.doi.org/10.1080/19393550802308618}, author = {Phithakkitnukoon, Santi and Ram Dantu and Baatarjav, Enkh-Amgalan} } @article {18, title = {Fast Worm Containment Using Feedback Control}, journal = {IEEE Transactions on Dependable and Secure Computing}, volume = {4}, year = {2007}, pages = {119 - 136}, abstract = {

In a computer network, network security is accomplished using elements such as firewalls, hosts, servers, routers, intrusion detection systems, and honey pots. These network elements need to know the nature or anomaly of the worm a priori to detect the attack. Modern viruses such as Code Red, Sapphire, and Nimda spread quickly. Therefore, it is impractical if not impossible for human mediated responses to these fast-spreading viruses. Several epidemic studies show that automatic tracking of resource usage and control provides an effective method to contain the damage. In this paper, we propose a novel security architecture based on the control system theory. In particular, we describe a state-space feedback control model that detects and control the spread of these viruses or worms by measuring the velocity of the number of new connections an infected host makes. The mechanism{\textquoteright}s objective is to slow down a worm{\textquoteright}s spreading velocity by controlling (delaying) the number of new connections made by an infected host. A proportional and integral (PI) controller is used for a continuous control of the feedback loop. The approach proposed here has been verified in a laboratory setup, and we were able to contain the infection so that it affected less than 5 percent of the hosts. We have also implemented a protocol for exchanging control-specific information between the network elements. The results from the simulation and experimental setup combined with the sensitivity analysis demonstrate the applicability and accuracy of the approach.

}, keywords = {communication/networking and information technology, computer networks, Computer systems organization, control engineering computing, general, invasive software, network security, network-level security and protection, PI control, process control systems., proportional-integral controller, special-purpose and application-based systems, state feedback, state-space feedback control, state-space methods, telecommunication security, worm containment}, doi = {10.1109/TDSC.2007.1002}, author = {Ram Dantu and Cangussu, Jo{\~a}o and Patwardhan, Sudeep} } @article {292, title = {Method and system for providing services for wireless data calls}, year = {2007}, month = {05/2007}, publisher = {Cisco Technology Inc}, address = {US}, abstract = {

A method and system for providing services for wireless data calls includes monitoring a wireless data call for a predefined event associated with a service for the wireless data call. The service is initiated for the wireless data call in response to detecting the predefined event for the data call. The predefined event may comprise a uniform resource locator (URL) match or change, excess use of transmission or time resources, a location change of a mobile device for the wireless data call, a network event, or a combination of any or all suitable events.

}, keywords = {call, data, network, service, wireless}, issn = {US7225238B1}, url = {https://patents.google.com/patent/US7225238/en}, author = {Ram Dantu and Patel, Pulin and Patel, Pravir and Garbuz, Alexander and Miernik, Jerzy and Patel, Achal and Holur, Balaji} } @conference {45, title = {Predicting Calls: New Service for an Intelligent Phone}, booktitle = {10th IFIP/IEEE International Conference on Management of Multimedia and Mobile Networks and Services, MMNS 2007}, year = {2007}, month = {11/2007}, address = { San Jos{\'e}, USA}, abstract = {

Predicting future calls can be the next advanced feature of the intelligent phone as the phone service providers are looking to offer new services to their customers. Call prediction can be useful to many applications such as planning daily schedule and attending unwanted communications (e.g. voice spam). Predicting calls is a very challenging task. We believe that this is a new area of research. In this paper, we propose a Call Predictor (CP) that computes the probability of receiving calls and makes call prediction based on caller{\textquoteright}s behavior and reciprocity. The proposed call predictor is tested with the actual call logs. The experimental results show that the call predictor performs reasonably well with false positive rate of 2.4416\%, false negative rate of 2.9191\%, and error rate of 5.3606\%.

}, keywords = {Arrival time, behavior, call matrix, Callee, Caller, Communications, Incoming calls, Inter-arrival time, Inter-arrival/departure time, Kernel density estimation, Outgoing calls, Probability density function (pdf), Receiving call probability, Reciprocity}, doi = {10.1007/978-3-540-75869-3\_3}, author = {Phithakkitnukoon, Santi and Ram Dantu} } @conference {86, title = {Unwanted SMTP Paths and Relays}, booktitle = {2007 2nd International Conference on Communication Systems Software and Middleware}, year = {2007}, month = {Jan}, abstract = {

Based on the social interactions of an email user, incoming email traffic can be divided into different categories such as, telemarketing, Opt-in family members and friends. Due to a lack of knowledge in the different categories, most of the existing spam filters are prone to high false positives and false negatives. Moreover, a majority of the spammers obfuscate their email content inorder to circumvent the content-based spam filters. However, they do not have access to all the fields in the email header. Our classification method is based on the path traversed by email (instead of content analysis) since we believe that spammers cannot forge all the fields in the email header. We based our classification on three kinds of analyses on the header: i) EndToEnd path analysis, which tries to establish the legitimacy of the path taken by an email and classifies them as either spam or non-spam; ii) Relay analysis, which verifies the trustworthiness of the relays participating in the relaying of emails; iii) Emails wantedness analysis, which measure the recipients wantedness of the senders emails. We use the IMAP message status flags such as, message has been read, deleted, answered, flagged, and draft as an implicit feed back from the user in Emails wantedness analysis. Finally we classify the incoming emails as i) socially close (such as, legitimate emails from family, and friends), ii) socially distinct emails from strangers, iii) spam emails (for example, emails from telemarketers, and spammers) and iv) opt-in emails. Based on the relation between spamminess of the path taken by spam emails and the unwantedness values of the spammers, we classify spammers as i) prospective spammers, ii) suspects, iii) recent spammers and iv) serial spammers. Overall, our method resulted in far less false positives compared to current filters like SpamAssassin. We achieved a precision of 98.65\% which is better than the precisions achieved by SPF and DNSBL blacklists.

}, keywords = {Computer science, content-based spam filters, Counterfeiting, Credit cards, email spam filters, emails wantedness analysis, end-to-end path analysis, Filters, IMAP message status flags, information filtering, information filters, Information security, Legislation, Multimedia communication, relay analysis, Relays, SMTP paths analysis, unsolicited e-mail, Unsolicited electronic mail, Web page design}, doi = {10.1109/COMSWA.2007.382440}, author = {Palla, Srikanth and Ram Dantu} } @conference {239, title = {Detecting phishing in emails}, booktitle = {Proceedings of MIT Spam Conference}, year = {2006}, author = {Palla, Srikanth and Ram Dantu} } @article {79, title = {Dynamic resource management in QoS controlled networks}, journal = {Telecommunication Systems}, volume = {32}, year = {2006}, pages = {11{\textendash}30}, abstract = {

This paper addresses the problem of resource fragmentation (RF) in QoS controllednetworks. Resources are said to be fragmented when they are available in non-contiguousblocks and hence cannot be utilized by incoming calls with high resource demands. This paper shows the effect of resource fragmentation on QoS controlled networks and presents the Dynamic Resource Redistribution (DRR) algorithm to counteract RF. The DRR algorithm reduces the effects of RF by attempting to redistribute resources in different paths to make resources to incoming calls. A variety of simulation experiments were conducted to study the performance of the DRR algorithm on different network topologies with varying traffic characteristics. The DRR algorithm, when used, increased the number of calls accommodated in the network as well as the overall resource allocation in the network.

}, issn = {1572-9451}, doi = {10.1007/s11235-006-8200-4}, url = {http://dx.doi.org/10.1007/s11235-006-8200-4}, author = {Prasanna, Venkatesan and Mikler, Armin and Ram Dantu and Abbas, Kaja} } @article {287, title = {Method and system for configuring wireless routers and networks}, year = {2006}, month = {04/2006}, publisher = {Cisco Technology Inc}, address = {US}, abstract = {

A method and system for configuring a wireless router and a wireless communications network includes establishing connectivity between a wireless router and at least one wireline router. Connectivity between the wireless router and a plurality of neighboring wireless routers is established through the wireline router. The wireless router is configured based on information exchanged with the neighboring wireless routers through the wireline router.

}, keywords = {parameters, router, state, step, wireless}, issn = {US7031266B1}, url = {https://patents.google.com/patent/US7031266/en}, author = {Patel, Pulin and Choksi, Ojas and Davidson, Kenneth and Ram Dantu} } @article {296, title = {Wireless router and method for processing traffic in a wireless communications network}, year = {2006}, month = {06/2006}, publisher = {Cisco Technology Inc}, address = {US}, abstract = {

A wireless communications network includes a wireless-specific router topology layer that connects cellular sites to a wireline topology. The wireless-specific router topology provides a distributed architecture in which call processing including call setup, resource preservation, air bandwidth allocation, switching, soft handoff, and micromobility is performed at the cell level. The wireless routers are technology independent to support various cellular technologies. The wireless router may include a first interface operable to communicate wireless packets for a call with a remote device and a second interface operable to communicate wireline packets for the call with the wireline network. A traffic controller is coupled to the first and second interfaces and operable to convert traffic between the wireless and wireline packets and to route packets to a destination mobile or wireline device. A selection and distribution unit is operable to select and distribute traffic to support soft handoff for calls in the wireless communications network.

}, keywords = {network, router, routers, traffic, wireless}, issn = {US7068624B1}, url = {https://patents.google.com/patent/US7068624B1/en}, author = {Ram Dantu and Patel, Pulin and Choksi, Ojas and Patel, Achal and Ali, Mohammad and Miernik, Jerzy and Holur, Balajl} } @article {275, title = {Parallel algorithms for low-level vision on the homogeneous multiprocessor}, journal = {Computers \& Electrical Engineering}, volume = {20}, year = {1994}, pages = {51 - 60}, abstract = {

In this work, we present the parallel implementation of three low-level vision algorithms, namely smoothing, histogram generation and edge detection by using the Sobel operator on the Homogeneous Multiprocessor. These algorithms were run on the simulator specifically developed for the Homogeneous Multiprocessor and the simulation experiments were used to establish the performance of these algorithms on the proposed architecture.

}, keywords = {Computer architecture, image processing, MIMO architecture, Multiprocessing, pattern recognition, vision}, issn = {0045-7906}, doi = {https://doi.org/10.1016/0045-7906(94)90006-X}, url = {http://www.sciencedirect.com/science/article/pii/004579069490006X}, author = {Ram Dantu and Dimopoulos, Nikitas and Li, Kinfu and Patel, Rajni and Al-Khalili, Asim} } @article {276, title = {Depth perception using blurring and its application in VLSI wafer probing}, journal = {Machine Vision and Applications}, volume = {5}, year = {1992}, month = {12/1992}, pages = {35{\textendash}45}, abstract = {

In this paper, we present a technique for measuring the amount of blur of an edge and using this information to determine the distance of a micromanipulator probe from a wafer surface in very large scale integration (VLSI) wafer probing. In this application, a soft and reliable touch of the probe with a metal pad in the wafer is a sensitive operation. The wafer is focused and several images of the probe while approaching the wafer are analyzed. In our theory, the amount of blur is calculated from the height of the step edge and the slope of the intensity profile at the zero crossing. Hence, our formula is simple and easy to use. We estimate the distance of the probe from the surface of the wafer and obtain a robust measure, i.e., one which is valid even in the presence of significant noise in the images. In order to validate our methods, we have experimented with various VLSI patterns as backgrounds.

}, issn = {1432-1769}, doi = {10.1007/BF01213528}, url = {https://doi.org/10.1007/BF01213528}, author = {Ram Dantu and Dimopoulos, Nikitas and Patel, Rajni and Al-Khalili, Asim} } @booklet {283, title = {Vision Algorithms For VLSI Wafer Probing}, year = {1990}, abstract = {

This paper deals with an important problem encountered in automating VLSI wafer probing. In this automation, vision is used for accurately guiding and lowering a probe to make contact with the wafer. In this paper, we discuss various algorithms used in measurement of the distance of the micro-manipulator from the wafer surface. In particular, we describe algorithms for alignment of consecutive frames of the wafer, separation of probe and wafer regions, and getting a clean image of the probe by eliminating traces of the background patterns. We also describe a three-level procedure for obtaining the proximity of the probe from the wafer. These algorithms are verified with the experimental data.

}, doi = {10.1117/12.969934}, url = {https://doi.org/10.1117/12.969934}, author = {Ram Dantu and Patel, Rajni and Dimopoulos, Nikitas and Al-Khalili, Asim} } @article {277, title = {Micromanipulator vision for wafer probing}, journal = {IEEE Transactions on Semiconductor Manufacturing}, volume = {2}, year = {1989}, month = {08/1989}, pages = {114-117}, abstract = {

An overview is presented of a micromanipulator vision system for use in automating various functions during the testing of a wafer for semiconductor parameters and inspection of VLSI circuits. It is assumed that the wafer under test is not necessarily in its proper orientation. It is required that certain probes be lowered automatically onto certain pads to inject test vectors and to read the results for analysis. A methodology was developed for determining the position (especially the vertical distance from the target) of the tip of a probe, so that it can be guided accurately to its target pad. Standard image processing steps used for efficient feature extraction and registration of the target integrated circuit are outlined, and a method of obtaining the vertical distance of the tip of a probe from its target pad is presented. Two different criteria through which it can be established whether a probe is in contact with its target are given. The algorithm developed was tested for touch using different types of tips such as tungsten and tungsten carbide, and with NMOS and CMOS processes. Clean and accurate representations of the probes were extracted from integrated images in all the tests, and in all cases, touch was achieved without the surface being scratched

}, keywords = {Automatic testing, automating various functions, Circuit testing, CMOS processes, computer vision, computerised picture processing, efficient feature extraction, image processing steps, Inspection, inspection of VLSI circuits, Machine vision, micromanipulator vision system, Micromanipulators, NMOS ICs, overview, Probes, registration, Semiconductor device testing, System testing, Tungsten, vertical distance, Very large scale integration, VLSI, W tip, wafer probing, WC tip}, issn = {0894-6507}, doi = {10.1109/66.29680}, author = {Ram Dantu and Dimopoulos, Nikitas and Patel, Rajni and Al-Khalili, Asim} } @conference {284, title = {A micro-manipulator vision in IC Manufacturing}, booktitle = {Proceedings. 1988 IEEE International Conference on Robotics and Automation}, year = {1988}, month = {Apr}, abstract = {

An overview is presented of a micromanipulator vision system for use in automating various functions during the testing of a wafer for semiconducting parameters and inspection of VLSI circuits. Positioning the probe and touching a test pad are the chief concern of the work desired. A brief description of the experimental setup is given. The image processing techniques used in identifying and controlling the location of various components such as the probes and the test pads are discussed. The vision modules and an expert system using hierarchical plan generation to control the sequence of plans are included

}, keywords = {Automatic testing, Circuit testing, computer vision, computer vision module, computerised pattern recognition, expert system, expert systems, IC Manufacturing, image processing, industrial robots, Inspection, integrated circuit manufacture, integrated circuit testing, Machine vision, Manufacturing, micromanipulator vision, Micromanipulators, Probes, robots, Semiconductivity, Semiconductor device manufacture, Semiconductor device testing, System testing, test pads, VLSI, wafer testing}, doi = {10.1109/ROBOT.1988.12271}, author = {Ram Dantu and Dimopoulos, Nikitas and Patel, Rajni and Al-Khalili, Asim} }