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Avdelning Institution Division Department Datum Date 2005-03-21 Institutionen för datavetenskap 581 83 LINKÖPING Språk Language Svenska/Swedish X Engelska/English Rapporttyp Report category Licentiatavhandling X Examensarbete C-uppsats D-uppsats Övrig rapport ISBN ISRN LITH-IDA-EX--05/029--SE Serietitel och serienummer Title of series numbering ISSN URL för elektronisk version http://www.ep.liu.se/exjobb/ida/2005/dd-d/029/ Titel Title Författare Author E-bedrägerier situationen idag och åtgärder E-fraud E-fraud state of the art and counter measures Bengt Bergman Sammanfattning Abstract This thesis investigates fraud and the situation on Internet with e-commerce today to point on some potential threats and needed countermeasures. The work reviews several state of the art e-fraud schemes techniques used in the schemes and statistics on the extent of e-fraud. This part shows that e-frauds are today both sophisticated and widespread. Since real world frauds are deemed impossible to fully cover in order to predict potential new e-frauds the thesis adopts a different approach. It suggests two abstraction models for fraud cases a protocol model and a functional model. These are used to perform analysis on case studies on both telecom frauds and e-frauds. The analysis presents characteristics for both types of frauds. Using one of the abstraction models the functional model conceptually similar cases among telecom frauds as well as e-fraud cases are identified. The similar cases in each category are then compared using the other abstraction model the protocol model. The study shows that concepts from telecom frauds already exist in e-frauds. Several challenges and some possibilities in e-fraud prevention and detection are also extracted in the comparative study of the different categories. The major consequence of the challenges is e-frauds higher scalability compared to telecom frauds. Finally this thesis covers several existing countermeasures in e-commerce along with specific countermeasures against auction fraud phishing and spam. However it is shown that these countermeasures do not address the challenges in e-fraud prevention and detection to a satisfactory extent. Therefore this thesis proposes several high-level countermeasures in order to address the challenges. Nyckelord Keyword E-fraud e-commerce telecom fraud fraud detection fraud classifications
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