UNSUPERVISED CONTROLLING SYSTEM FOR DETECTING AND DEFENCING SYBIL ATTACK

摘要

Disclosed is an unsupervised control system for detecting and defending from a Sybil attack, which can detect and defend from the Sybil attack to an online recommendation system. The unsupervised control system for detecting and defending from the Sybil attack according to an embodiment of the present invention comprises: an initial setup unit calculating an average value from a plurality of grade information sets given to a recommendation target on the online recommendation system and calculating reliability from the average value; a certification control unit comparing the reliability with a threshold interval during a time interval for detecting the Sybil attack to determine whether new grade information given to the recommendation target is certified and reflecting the new grade information according to a preset number of updates to update the reliability; and a system determination unit determining whether the Sybil attack to the recommendation target is performed and dynamically changing the preset threshold interval and the number of updates according to the determination result.