Unified defense against DDoS attacks

With DoS/DDoS attacks emerging as one of the primary security threats in today's Internet, the search is on for an efficient DDoS defense mechanism that would provide attack prevention, mitigation and traceback features, in as few packets as possible and with no collateral damage. Although several techniques have been proposed to tackle this growing menace, there exists no effective solution to date, due to the growing sophistication of the attacks and also the increasingly complex Internet architecture. In this paper, we propose an unified framework that integrates traceback and mitigation capabilities for an effective attack defense. Some significant aspects of our approach include: (1) a novel data cube model to represent the traceback information, and its slicing along the lines of path signatures rather than router signatures, (2) characterizing traceback as a transmission scheduling problem on the data cube representation, and achieving scheduling optimality using a novel metric called utility, (3) and finally an information delivery architecture employing both packet marking and data logging in a distributed manner to achieve faster response times. The proposed scheme can thus provide both per-packet mitigation and multi-packet traceback capabilities due to effective data slicing of the cube, and can attain higher detection speeds due to novel utility rate analysis. We also contrast this unified scheme with other well-known schemes in literature to understand the performance tradeoffs, while providing an experimental evaluation of the proposed scheme on real data sets.